40 CFR 89.329 - Engine cooling system.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine cooling system. 89.329 Section...) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Emission Test Equipment Provisions § 89.329 Engine cooling system. An engine cooling system is required with sufficient capacity to...

40 CFR 91.307 - Engine cooling system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine cooling system. 91.307 Section...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.307 Engine cooling system. An engine cooling system is required with sufficient capacity to maintain the engine at...

40 CFR 90.307 - Engine cooling system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine cooling system. 90.307 Section...) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Emission Test Equipment Provisions § 90.307 Engine cooling system. An engine cooling system is required with sufficient capacity to...

40 CFR 89.329 - Engine cooling system.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine cooling system. 89.329 Section...) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Emission Test Equipment Provisions § 89.329 Engine cooling system. An engine cooling system is required with sufficient capacity to...

30 CFR 36.48 - Tests of surface temperature of engine and components of the cooling system.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Tests of surface temperature of engine and... temperature of engine and components of the cooling system. (a) The surface temperatures of the engine... components shall have reached their respective equilibrium temperatures. The exhaust cooling system shall be...

30 CFR 36.48 - Tests of surface temperature of engine and components of the cooling system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Tests of surface temperature of engine and... temperature of engine and components of the cooling system. (a) The surface temperatures of the engine... components shall have reached their respective equilibrium temperatures. The exhaust cooling system shall be...

30 CFR 36.48 - Tests of surface temperature of engine and components of the cooling system.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Tests of surface temperature of engine and... temperature of engine and components of the cooling system. (a) The surface temperatures of the engine... components shall have reached their respective equilibrium temperatures. The exhaust cooling system shall be...

Coupled reactor kinetics and heat transfer model for heat pipe cooled reactors

NASA Astrophysics Data System (ADS)

Wright, Steven A.; Houts, Michael

2001-02-01

Heat pipes are often proposed as cooling system components for small fission reactors. SAFE-300 and STAR-C are two reactor concepts that use heat pipes as an integral part of the cooling system. Heat pipes have been used in reactors to cool components within radiation tests (Deverall, 1973); however, no reactor has been built or tested that uses heat pipes solely as the primary cooling system. Heat pipe cooled reactors will likely require the development of a test reactor to determine the main differences in operational behavior from forced cooled reactors. The purpose of this paper is to describe the results of a systems code capable of modeling the coupling between the reactor kinetics and heat pipe controlled heat transport. Heat transport in heat pipe reactors is complex and highly system dependent. Nevertheless, in general terms it relies on heat flowing from the fuel pins through the heat pipe, to the heat exchanger, and then ultimately into the power conversion system and heat sink. A system model is described that is capable of modeling coupled reactor kinetics phenomena, heat transfer dynamics within the fuel pins, and the transient behavior of heat pipes (including the melting of the working fluid). This paper focuses primarily on the coupling effects caused by reactor feedback and compares the observations with forced cooled reactors. A number of reactor startup transients have been modeled, and issues such as power peaking, and power-to-flow mismatches, and loading transients were examined, including the possibility of heat flow from the heat exchanger back into the reactor. This system model is envisioned as a tool to be used for screening various heat pipe cooled reactor concepts, for designing and developing test facility requirements, for use in safety evaluations, and for developing test criteria for in-pile and out-of-pile test facilities. .

Cooling for SC devices of test cryomodule for ADS Injector II at IMP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, L.; Wang, S. Y.; Sun, S.

2014-01-29

The superconducting half-wave resonance cavities connected in series with superconducting solenoids will be applied to the Injector II of the Accelerator Driven Sub-critical System (ADS) to be built at the Modern Physics Institute, China. A test system has been developed for the purpose of performance test of the HWR cavities as well as validating the relevant technique for cooling the cavity and the solenoids together. It mainly comprises a cryogenic valve box (TVB), a test cryomodule (TCM1) and transfer lines. The TCM1 includes one HWR cavity, two superconducting solenoids, one cold BPM and their cooling system. The design of themore » TCM1 cryostat was carried out by the Shanghai Institute of Applied Physics (SINAP), CAS. Both the cavity and the solenoids will work at 4.4 K by bath cooling. The fast cooling down for the cavity from around 100 K to 120 K is required to avoid degrading of the cavity performance. After cool down and before energization, the solenoids should be warmed up to above 10 K and re-cooled down for the purpose of degaussing. The TCM1 can not only be cooled by using the dewar-filling system, but also operated by the refrigerator system. For the purpose of reducing the heat loads to the cold mass at 4 K from room temperature, thermal radiation shields cooled by liquid nitrogen flowing in tubing were employed. This paper presents the design details of cooling circuits and thermal shields of the TCM1 as well as related calculations and analyses.« less

Cooling for SC devices of test cryomodule for ADS Injector II at IMP

NASA Astrophysics Data System (ADS)

Wang, L.; Wang, S. Y.; Sun, S.; Guo, X. L.; Wang, S. H.; Liu, Y. Y.

2014-01-01

The superconducting half-wave resonance cavities connected in series with superconducting solenoids will be applied to the Injector II of the Accelerator Driven Sub-critical System (ADS) to be built at the Modern Physics Institute, China. A test system has been developed for the purpose of performance test of the HWR cavities as well as validating the relevant technique for cooling the cavity and the solenoids together. It mainly comprises a cryogenic valve box (TVB), a test cryomodule (TCM1) and transfer lines. The TCM1 includes one HWR cavity, two superconducting solenoids, one cold BPM and their cooling system. The design of the TCM1 cryostat was carried out by the Shanghai Institute of Applied Physics (SINAP), CAS. Both the cavity and the solenoids will work at 4.4 K by bath cooling. The fast cooling down for the cavity from around 100 K to 120 K is required to avoid degrading of the cavity performance. After cool down and before energization, the solenoids should be warmed up to above 10 K and re-cooled down for the purpose of degaussing. The TCM1 can not only be cooled by using the dewar-filling system, but also operated by the refrigerator system. For the purpose of reducing the heat loads to the cold mass at 4 K from room temperature, thermal radiation shields cooled by liquid nitrogen flowing in tubing were employed. This paper presents the design details of cooling circuits and thermal shields of the TCM1 as well as related calculations and analyses.

Hemodynamic Responses to Head and Neck Cooling

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Carbo, Jorge E.; Montgomery, Leslie D.; Webbon, Bruce W.

1994-01-01

Personal thermoregulatory systems which provide head and neck cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objective of this study was to measure the scalp temperature and circulatory responses during use of one commercially available thermal control system. The Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used in this study. Two EEG electrodes and one skin temperature transducer were placed on the anterior midline of the scalp to measure the scalp blood and temperature. Blood flow was measured using a bipolar impedance rheograph. Ten subjects, seated in an upright position at normal room temperature, were tested at high, medium, moderate, moderate-low and low coolant temperatures. Scalp blood flow was recorded continuously using a computer data acquisition system with a sampling frequency of 200 Hz. Scalp temperature and cooling helmet Inlet temperature was logged periodically during the test period. This study quantifies the effect of head cooling upon scalp temperature and blood flow. These data may also be used to select operational specifications of the head cooling system for biomedical applications such as the treatment of migraine headaches, scalp cooling during chemotherapy, and cooling of multiple sclerosis patients.

Physiologic and Functional Responses of MS Patients to Body Cooling Using Commercially Available Cooling Garments

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Montgomery, Leslie D.; Lee, Hank C.; Luna, Bernadette; Webbon, Bruce W.; Mead, Susan C. (Technical Monitor)

1999-01-01

Personal cooling systems are widely used in industrial and aerospace environments to alleviate thermal stress. Increasingly they are also used by heat sensitive multiple sclerosis (HSMS) patients to relieve symptoms and improve quality of life. There are a variety of cooling systems commercially available to the MS community. However, little information is available regarding the comparative physiological changes produced by routine operation of these various systems. The objective of this study was to document and compare the patient response to two passive cooling vests and one active cooling garment. The Life Enhancement Technology, Inc. (LET) lightweight active cooling vest with cap, the MicroClimate Systems (MCS) Change of Phase garment, and the Steele Vest were each used to cool 13 male and 13 female MS subjects (31 to 67 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approximately 22 C), were tested with one of the cooling garments. Oral, fight and left ear temperatures were logged manually every 5 min. An-n, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. Each subject was given a series of subjective and objective evaluation tests before and after cooling. The LET and Steele vests test groups had similar, significant (P less than 0.01) cooling effects on oral and ear canal temperature, which decreased approximately 0.4 C, and 0.3 C, respectively. Core temperature increased (N.S.) with all three vests during cooling. The LET vest produced the coldest (P less than 0.01) skin temperature. Overall, the LET vest provided the most improvement on subjective and objective performance measures. These results show that the garment configurations tested do not elicit a similar thermal response in all MS patients. Cooling with the LET active garment configuration resulted in the lowest body temperatures for the MS subjects; cooling with the MCS vest was least effective. For functional responses, the LET test group performed better than the other two vests.

Asetek's Warm-Water Liquid Cooling System Yields Energy Cost Savings at

Science.gov Websites

NREL | Energy Systems Integration Facility | NREL Asetek Asetek's Warm-Water Liquid Cooling System Yields Energy Cost Savings at NREL Asetek's RackCDU liquid cooling system was installed and tested at the Energy Systems Integration Facility's (ESIF's) ultra-energy-efficient high-performance

Design, Fabrication, and Testing of an Auxiliary Cooling System for Jet Engines

NASA Technical Reports Server (NTRS)

Leamy, Kevin; Griffiths, Jim; Andersen, Paul; Joco, Fidel; Laski, Mark; Balser, Jeffrey (Technical Monitor)

2001-01-01

This report summarizes the technical effort of the Active Cooling for Enhanced Performance (ACEP) program sponsored by NASA. It covers the design, fabrication, and integrated systems testing of a jet engine auxiliary cooling system, or turbocooler, that significantly extends the use of conventional jet fuel as a heat sink. The turbocooler is designed to provide subcooled cooling air to the engine exhaust nozzle system or engine hot section. The turbocooler consists of three primary components: (1) a high-temperature air cycle machine driven by engine compressor discharge air, (2) a fuel/ air heat exchanger that transfers energy from the hot air to the fuel and uses a coating to mitigate fuel deposits, and (3) a high-temperature fuel injection system. The details of the turbocooler component designs and results of the integrated systems testing are documented. Industry Version-Data and information deemed subject to Limited Rights restrictions are omitted from this document.

Initial operation of a solar heating and cooling system in a full-scale solar building test facility

NASA Technical Reports Server (NTRS)

Knoll, R. H.; Miao, D.; Hamlet, I. L.; Jensen, R. N.

1976-01-01

The Solar Building Test Facility (SBTF) was constructed to advance the technology for heating and cooling of office buildings with solar energy. Its purposes are to (1) test system components which include high-performing collectors, (2) test the performance of a complete solar heating and cooling system, (3) investigate component interactions, and (4) investigate durability, maintenance and reliability of components. The SBTF consists of a 50,000 square foot office building modified to accept solar heated water for operation of an absorption air conditioner and for the baseboard heating system. A 12,666 square foot solar collector field with a 30,000 gallon storage tank provides the solar heated water. A description of the system and the collectors selected is printed along with the objectives, test approach, expected system performance, and some preliminary results.

The Structural Heat Intercept-Insulation-Vibration Evaluation Rig (SHIVER)

NASA Technical Reports Server (NTRS)

Johnson, W. L.; Zoeckler, J. G.; Best-Ameen, L. M.

2015-01-01

NASA is currently investigating methods to reduce the boil-off rate on large cryogenic upper stages. Two such methods to reduce the total heat load on existing upper stages are vapor cooling of the cryogenic tank support structure and integration of thick multilayer insulation systems to the upper stage of a launch vehicle. Previous efforts have flown a 2-layer MLI blanket and shown an improved thermal performance, and other efforts have ground-tested blankets up to 70 layers thick on tanks with diameters between 2 3 meters. However, thick multilayer insulation installation and testing in both thermal and structural modes has not been completed on a large scale tank. Similarly, multiple vapor cooled shields are common place on science payload helium dewars; however, minimal effort has gone into intercepting heat on large structural surfaces associated with rocket stages. A majority of the vapor cooling effort focuses on metallic cylinders called skirts, which are the most common structural components for launch vehicles. In order to provide test data for comparison with analytical models, a representative test tank is currently being designed to include skirt structural systems with integral vapor cooling. The tank is 4 m in diameter and 6.8 m tall to contain 5000 kg of liquid hydrogen. A multilayer insulation system will be designed to insulate the tank and structure while being installed in a representative manner that can be extended to tanks up to 10 meters in diameter. In order to prove that the insulation system and vapor cooling attachment methods are structurally sound, acoustic testing will also be performed on the system. The test tank with insulation and vapor cooled shield installed will be tested thermally in the B2 test facility at NASAs Plumbrook Station both before and after being vibration tested at Plumbrooks Space Power Facility.

Development of New Cooling System Using Gm/jt Cryocoolers for the SKS Magnet

NASA Astrophysics Data System (ADS)

Aoki, K.; Haruyama, T.; Makida, Y.; Araoka, O.; Kasami, K.; Takahashi, T.; Nagae, T.; Kakiguchi, Y.; Sekimoto, M.; Tosaka, T.; Miyazaki, H.; Kuriyama, T.; Ono, M.; Orikasa, T.; Tsuchihashi, T.; Hirata, Y.

2008-03-01

We plan to develop a new improved cooling system for the Superconducting Kaon Spectrometer (SKS) magnet and transfer the magnet to the K1.8 beamline of the Hadron Hall of the Japan Proton Accelerator Research Complex (J-PARC) for further use in nuclear physics experiments. To replace the present 300 W cryogenic system, we will adopt a new cooling method that uses 4 K Gifford-McMahon/Joule-Thomson (GM/JT) cryocoolers. In order to decide a practical design for the new liquid helium reservoir of the magnet, which will be equipped with GM/JT cryocoolers, cooling tests on a GM/JT cryocooler were performed from February to March 2007. We constructed a new cooling test stand with a GM/JT cryocooler and measured the cooling capacities under several thermal shield temperatures with or without a baffle, which helped prevent convection. Based on the test results, we have finally decided to adopt three GM/JT cryocoolers for the new SKS along with a baffle and an additional dedicated GM cooler to cool the thermal shield of the GM/JT ports.

Development and testing of heat transport fluids for use in active solar heating and cooling systems

NASA Technical Reports Server (NTRS)

Parker, J. C.

1981-01-01

Work on heat transport fluids for use with active solar heating and cooling systems is described. Program objectives and how they were accomplished including problems encountered during testing are discussed.

Hemodynamic and thermal responses to head and neck cooling in men and women

NASA Technical Reports Server (NTRS)

Ku, Y. T.; Montgomery, L. D.; Webbon, B. W.

1996-01-01

Personal cooling systems are used to alleviate symptoms of multiple sclerosis and to prevent increased core temperature during daily activities. The objective of this study was to determine the operating characteristics and the physiologic changes produced by short term use of one commercially available thermal control system. A Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used to cool the head and neck regions of 12 female and 12 male subjects (25-55 yr) in this study. The healthy subjects, seated in an upright position at normal room temperature (approximately 21 degrees C), were tested for 30 min with the liquid cooling garment operated at its maximum cooling capacity. Electrocardiograms and scalp and intracranial blood flows were recorded periodically during each test sequence. Scalp, right and left ear, and oral temperatures and cooling system parameters were logged every 5 min. Scalp, right and left ear canal, and oral temperatures were all significantly (P <0.05) reduced by 30 min of head and neck cooling. Oral temperatures decreased approximately 0.2-0.6 degrees C after 30 min and continued to decrease further (approximately 0.1-0.2 degrees C) for a period of approximately 10 min after removal of the cooling helmet. Intracranial blood flow decreased significantly (P < 0.05) during the first 10 min of the cooling period. Both right and left ear temperatures in the women were significantly lower than those of the men during the cooling period. These data indicate that head and neck cooling may be used to reduce core temperature to that needed for symptomatic relief of both male and female multiple sclerosis patients. This study quantifies the operating characteristics of one liquid cooling garment as an example of the information needed to compare the efficiency of other garments operated under different test conditions.

77 FR 64148 - Advisory Committee on Reactor Safeguards (ACRS) Meeting of the ACRS Subcommittee on Regulatory...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-18

... Regulatory Guides (RG) RG 1.79, ````Preoperational Testing of Emergency Core Cooling Systems for Pressurized Water Reactors,'' Revision 2 and RG 1.79.1, ``Initial Test Program of Emergency Core Cooling Systems for...

Investigation of Spray Cooling Schemes for Dynamic Thermal Management

NASA Astrophysics Data System (ADS)

Yata, Vishnu Vardhan Reddy

This study aims to investigate variable flow and intermittent flow spray cooling characteristics for efficiency improvement in active two-phase thermal management systems. Variable flow spray cooling scheme requires control of pump input voltage (or speed), while intermittent flow spray cooling scheme requires control of solenoid valve duty cycle and frequency. Several testing scenarios representing dynamic heat load conditions are implemented to characterize the overall performance of variable flow and intermittent flow spray cooling cases in comparison with the reference, steady flow spray cooling case with constant flowrate, continuous spray cooling. Tests are conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. HFE-7100 dielectric liquid is selected as the working fluid. Two types of test samples are prepared on 10 mm x 10 mm x 2 mm copper substrates with matching size thick film resistors attached onto the opposite side, to generate heat and simulate high heat flux electronic devices. The test samples include: (i) plain, smooth surface, and (ii) microporous surface featuring 100 ?m thick copper-based coating prepared by dual stage electroplating technique. Experimental conditions involve HFE-7100 at atmospheric pressure and 30°C and 10°C subcooling. Steady flow spray cooling tests are conducted at flow rates of 2-5 ml/cm2.s, by controlling the heat flux in increasing steps, and recording the corresponding steady-state temperatures to obtain cooling curves in the form of surface superheat vs. heat flux. Variable flow and intermittent flow spray cooling tests are done at selected flowrate and subcooling conditions to investigate the effects of dynamic flow conditions on maintaining the target surface temperatures defined based on reference steady flow spray cooling performance.

Solar heating and cooling systems design and development

NASA Technical Reports Server (NTRS)

1977-01-01

The development and delivery of eight prototype solar heating and cooling systems for installation and operational test was reported. Two heating and six heating and cooling units will be delivered for single family residences, multiple family residences and commercial applications.

78 FR 64027 - Preoperational Testing of Emergency Core Cooling Systems for Pressurized-Water Reactors

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

...The U.S. Nuclear Regulatory Commission (NRC) is issuing a revision to regulatory guide (RG), 1.79, ``Preoperational Testing of Emergency Core Cooling Systems for Pressurized-Water Reactors.'' This RG is being revised to incorporate guidance for preoperational testing of new pressurized water reactor (PWR) designs.

Design of Test Support Hardware for Advanced Space Suits

NASA Technical Reports Server (NTRS)

Watters, Jeffrey A.; Rhodes, Richard

2013-01-01

As a member of the Space Suit Assembly Development Engineering Team, I designed and built test equipment systems to support the development of the next generation of advanced space suits. During space suit testing it is critical to supply the subject with two functions: (1) cooling to remove metabolic heat, and (2) breathing air to pressurize the space suit. The objective of my first project was to design, build, and certify an improved Space Suit Cooling System for manned testing in a 1-G environment. This design had to be portable and supply a minimum cooling rate of 2500 BTU/hr. The Space Suit Cooling System is a robust, portable system that supports very high metabolic rates. It has a highly adjustable cool rate and is equipped with digital instrumentation to monitor the flowrate and critical temperatures. It can supply a variable water temperature down to 34 deg., and it can generate a maximum water flowrate of 2.5 LPM. My next project was to design and build a Breathing Air System that was capable of supply facility air to subjects wearing the Z-2 space suit. The system intakes 150 PSIG breathing air and regulates it to two operating pressures: 4.3 and 8.3 PSIG. It can also provide structural capabilities at 1.5x operating pressure: 6.6 and 13.2 PSIG, respectively. It has instrumentation to monitor flowrate, as well as inlet and outlet pressures. The system has a series of relief valves to fully protect itself in case of regulator failure. Both projects followed a similar design methodology. The first task was to perform research on existing concepts to develop a sufficient background knowledge. Then mathematical models were developed to size components and simulate system performance. Next, mechanical and electrical schematics were generated and presented at Design Reviews. After the systems were approved by the suit team, all the hardware components were specified and procured. The systems were then packaged, fabricated, and thoroughly tested. The next step was to certify the equipment for manned used, which included generating a Hazard Analysis and giving a presentation to the Test Readiness Review Board. Both of these test support systems will perform critical roles in the development of next-generation space suits. They will used on a regular basis to test the NASA's new Z-2 Space Suit. The Space Suit Cooling System is now the primary cooling system for all advanced suit tests.

Design and experimental investigation of a cryogenic system for environmental test applications

NASA Astrophysics Data System (ADS)

Yan, Lutao; Li, Hong; Liu, Yue; Han, Che; Lu, Tian; Su, Yulei

2015-04-01

This paper is concerned with the design, development and performance testing of a cryogenic system for use in high cooling power instruments for ground-based environmental testing. The system provides a powerful tool for a combined environmental test that consists of high pressure and cryogenic temperatures. Typical cryogenic conditions are liquid hydrogen (LH2) and liquid oxygen (LO2), which are used in many fields. The cooling energy of liquid nitrogen (LN2) and liquid helium (LHe) is transferred to the specimen by a closed loop of helium cycle. In order to minimize the consumption of the LHe, the optimal design of heat recovery exchangers has been used in the system. The behavior of the system is discussed based on experimental data of temperature and pressure. The results show that the temperature range from room temperature to LN2 temperature can be achieved by using LN2, the pressurization process is stable and the high test pressure is maintained. Lower temperatures, below 77 K, can also be obtained with LHe cooling, the typical cooling time is 40 min from 90 K to 22 K. Stable temperatures of 22 K at the inlet of the specimen have been observed, and the system in this work can deliver to the load a cooling power of several hundred watts at a pressure of 0.58 MPa.

Emergency and microfog lubrication and cooling of bearings for Army helicopters

NASA Technical Reports Server (NTRS)

Rosenlieb, J. W.

1978-01-01

An analysis and system study was performed to provide design information regarding lubricant and coolant flow rates and flow paths for effective utilization of the lubricant and coolant in a once-through oil-mist (microfog) and coolant air system. A system was designed, manufactured, coupled with an existing rig and evaluation tests were performed using 46 mm bore split-inner angular-contact ball bearings under 1779N (400 lb.) thrust load. An emergency lubrication aspirator system was also manufactured and tested under lost lubricant conditions. The testing demonstrated the feasibility of using a mist oil and cooling air system to lubricate and cool a high speed helicopter engine mainshaft bearing. The testing also demonstrated the feasibility of using an emergency aspirator lubrication system as a viable survivability concept for helicopter mainshaft engine bearing for periods as long as 30 minutes.

A portable personal cooling system for mine rescue operations

NASA Technical Reports Server (NTRS)

Webbon, B.; Williams, B.; Kirk, P.; Elkins, W.; Stein, R.

1977-01-01

Design of a portable personal cooling system to reduce physiological stress in high-temperature, high-humidity conditions is discussed. The system, based on technology used in the thermal controls of space suits, employs a combination of head and thoracic insulation and cooling through a heat sink unit. Average metabolic rates, heart rates, rectal temperature increase and sweat loss were monitored for test subjects wearing various configurations of the cooling system, as well as for a control group. The various arrangements of the cooling garment were found to provide significant physiological benefits; however, increases in heat transfer rate of the cooling unit and more effective insulation are suggested to improve the system's function.

Prototype solar heating and combined heating cooling systems

NASA Technical Reports Server (NTRS)

1978-01-01

The design and development of eight prototype solar heating and combined heating and cooling systems is discussed. The program management and systems engineering are reported, and operational test sites are identified.

Application of Simulated Reactivity Feedback in Nonnuclear Testing of a Direct-Drive Gas-Cooled Reactor

NASA Technical Reports Server (NTRS)

Bragg-Sitton, S. M.; Webster, K. L.

2007-01-01

Nonnuclear testing can be a valuable tool in the development of an in-space nuclear power or propulsion system. In a nonnuclear test facility, electric heaters are used to simulate heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and full nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response and response characteristics, and assess potential design improvements with a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE 100a heat pipe cooled, electrically heated reactor and heat exchanger hardware. This Technical Memorandum discusses the status of the planned dynamic test methodology for implementation in the direct-drive gas-cooled reactor testing and assesses the additional instrumentation needed to implement high-fidelity dynamic testing.

Microfog lubrication for aircraft engine bearings

NASA Technical Reports Server (NTRS)

Rosenlieb, J. W.

1976-01-01

An analysis and system study was performed to provide design information regarding lubricant and coolant flow rates and flow paths for effective utilization of the lubricant and coolant in a once through bearing oil mist (microfog) and coolant air system. Both static and dynamic tests were performed. Static tests were executed to evaluate and calibrate the mist supply system. A total of thirteen dynamic step speed bearing tests were performed using four different lubricants and several different mist and air supply configurations. The most effective configuration consisted of supplying the mist and the major portion of the cooling air axially through the bearing. The results of these tests have shown the feasibility of using a once through oil mist and cooling air system to lubricate and cool a high speed, high temperature aircraft engine mainshaft bearing.

49 CFR 173.5b - Portable and mobile refrigeration systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... operations. These refrigeration systems are used at field sites to cool (pre-cool) produce before the produce... pressure vessel must be designed, manufactured, and maintained in accordance with applicable requirements... initial pressure test performed after manufacture. Additional pressure tests must be performed after any...

49 CFR 173.5b - Portable and mobile refrigeration systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... operations. These refrigeration systems are used at field sites to cool (pre-cool) produce before the produce... pressure vessel must be designed, manufactured, and maintained in accordance with applicable requirements... initial pressure test performed after manufacture. Additional pressure tests must be performed after any...

Passive Two-Phase Cooling for Automotive Power Electronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moreno, G.; Jeffers, J. R.; Narumanchi, S.

2014-01-01

Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated and tested using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245 fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm3 of HFC-245fa. An advanced evaporator concept that incorporates features to improve performance and reduce its size was designed. Simulation results indicate themore » concept's thermal resistance can be 58% to 65% lower than automotive dual-side-cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers-plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.« less

Passive Two-Phase Cooling of Automotive Power Electronics: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moreno, G.; Jeffers, J. R.; Narumanchi, S.

2014-08-01

Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated, and tests were conducted using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm3 of HFC-245fa. An advanced evaporator design that incorporates features to improve performance and reduce size was conceived. Simulation results indicate itsmore » thermal resistance can be 37% to 48% lower than automotive dual side cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers--plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.« less

Optimum design on refrigeration system of high-repetition-frequency laser

NASA Astrophysics Data System (ADS)

Li, Gang; Li, Li; Jin, Yezhou; Sun, Xinhua; Mao, Shaojuan; Wang, Yuanbo

2014-12-01

A refrigeration system with fluid cycle, semiconductor cooler and air cooler is designed to solve the problems of thermal lensing effect and unstable output of high-repetition-frequency solid-state lasers. Utilizing a circulating water pump, water recycling system carries the water into laser cavity to absorb the heat then get to water cooling head. The water cooling head compacts cold spot of semiconductor cooling chips, so the heat is carried to hot spot which contacts the radiating fins, then is expelled through cooling fan. Finally, the cooled water return to tank. The above processes circulate to achieve the purposes of highly effective refrigeration in miniative solid-state lasers.The refrigeration and temperature control components are designed strictly to ensure refrigeration effect and practicability. we also set up a experiment to test the performances of this refrigeration system, the results show that the relationship between water temperature and cooling power of semiconductor cooling chip is linear at 20°C-30°C (operating temperature range of Nd:YAG), the higher of the water temperature, the higher of cooling power. According to the results, cooling power of single semiconductor cooling chip is above 60W, and the total cooling power of three semiconductor cooling chips achieves 200W that will satisfy the refrigeration require of the miniative solid-state lasers.The performance parameters of laser pulse are also tested, include pulse waveform, spectrogram and laser spot. All of that indicate that this refrigeration system can ensure the output of high-repetition-frequency pulse whit high power and stability.

KRESS INDIRECT DRY COOLING SYSTEM, BETHLEHEM STEEL'S COKE PLANT DEMONSTRATION AT SPARROWS POINT, MARYLAND - VOLUME 2. APPENDICES G-N

EPA Science Inventory

The report evaluates the Kress Indirect Dry Cooling (KIDC) process, an innovative system for handling and cooling coke produced from a slot-type by-product coke oven battery. The report is based on the test work and demonstration of the system at Bethlehem Steel Corporation's Sp...

The development of a solar residential heating and cooling system

NASA Technical Reports Server (NTRS)

1975-01-01

The MSFC solar heating and cooling facility was assembled to demonstrate the engineering feasibility of utilizing solar energy for heating and cooling buildings, to provide an engineering evaluation of the total system and the key subsystems, and to investigate areas of possible improvement in design and efficiency. The basic solar heating and cooling system utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating, and an absorption cycle air conditioner for space cooling. A complete description of all systems is given. Development activities for this test system included assembly, checkout, operation, modification, and data analysis, all of which are discussed. Selected data analyses for the first 15 weeks of testing are included, findings associated with energy storage and the energy storage system are outlined, and conclusions resulting from test findings are provided. An evaluation of the data for summer operation indicates that the current system is capable of supplying an average of 50 percent of the thermal energy required to drive the air conditioner. Preliminary evaluation of data collected for operation in the heating mode during the winter indicates that nearly 100 percent of the thermal energy required for heating can be supplied by the system.

Solid cryogen: a cooling system for future MgB2 MRI magnet.

PubMed

Patel, Dipak; Hossain, Md Shahriar Al; Qiu, Wenbin; Jie, Hyunseock; Yamauchi, Yusuke; Maeda, Minoru; Tomsic, Mike; Choi, Seyong; Kim, Jung Ho

2017-03-02

An efficient cooling system and the superconducting magnet are essential components of magnetic resonance imaging (MRI) technology. Herein, we report a solid nitrogen (SN 2 ) cooling system as a valuable cryogenic feature, which is targeted for easy usability and stable operation under unreliable power source conditions, in conjunction with a magnesium diboride (MgB 2 ) superconducting magnet. The rationally designed MgB 2 /SN 2 cooling system was first considered by conducting a finite element analysis simulation, and then a demonstrator coil was empirically tested under the same conditions. In the SN 2 cooling system design, a wide temperature distribution on the SN 2 chamber was observed due to the low thermal conductivity of the stainless steel components. To overcome this temperature distribution, a copper flange was introduced to enhance the temperature uniformity of the SN 2 chamber. In the coil testing, an operating current as high as 200 A was applied at 28 K (below the critical current) without any operating or thermal issues. This work was performed to further the development of SN 2 cooled MgB 2 superconducting coils for MRI applications.

Solid cryogen: a cooling system for future MgB2 MRI magnet

NASA Astrophysics Data System (ADS)

Patel, Dipak; Hossain, Md Shahriar Al; Qiu, Wenbin; Jie, Hyunseock; Yamauchi, Yusuke; Maeda, Minoru; Tomsic, Mike; Choi, Seyong; Kim, Jung Ho

2017-03-01

An efficient cooling system and the superconducting magnet are essential components of magnetic resonance imaging (MRI) technology. Herein, we report a solid nitrogen (SN2) cooling system as a valuable cryogenic feature, which is targeted for easy usability and stable operation under unreliable power source conditions, in conjunction with a magnesium diboride (MgB2) superconducting magnet. The rationally designed MgB2/SN2 cooling system was first considered by conducting a finite element analysis simulation, and then a demonstrator coil was empirically tested under the same conditions. In the SN2 cooling system design, a wide temperature distribution on the SN2 chamber was observed due to the low thermal conductivity of the stainless steel components. To overcome this temperature distribution, a copper flange was introduced to enhance the temperature uniformity of the SN2 chamber. In the coil testing, an operating current as high as 200 A was applied at 28 K (below the critical current) without any operating or thermal issues. This work was performed to further the development of SN2 cooled MgB2 superconducting coils for MRI applications.

Prototype solar heating and combined heating and cooling systems

NASA Technical Reports Server (NTRS)

1976-01-01

Eight prototype solar heating and combined heating and cooling systems are considered. This effort includes development, manufacture, test, installation, maintenance, problem resolution, and performance evaluation.

Performance evaluation of Ormat unit at Wabuska, Nevada. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Culver, G.

1986-07-01

Three nominal 24 hour tests under summer, winter and spring weather conditions, were run on an Ormat geothermal binary power generation machine. The machine, located at TAD's Enterprises in Wabuska, Nevada is supplied with approximately 830 gpm of geothermal water at 221/sup 0/F and has two spray cooling ponds. During the tests, temperature, pressure, and flows of geothermal water, freon, cooling water and instantaneous electrical production were recorded hourly. At least once during each test, energy consumption of the well pump, freon feed pump and cooling water pumps were made. Power output of the machine is limited by spray pondmore » capacity. Net output ranged from 410.2 kW during summer conditions when cooling water was 65/sup 0/F to 610.4 kW during winter conditions when cooling water was 55/sup 0/F. Net resource utilization ranged from 1.005 Whr/lb during the summer test to 1.55 Whr/lb during the winter test. Spray pond performance averaged 63% for the fall and winter tests. Availability of the Ormat unit itself during the eight month test period was generally good, averaging 95.5%. Overall system availability, including well pumps, cooling system and electric grid was somewhat less - averaging 83%.« less

Next-generation avionics packaging and cooling 'test results from a prototype system'

NASA Astrophysics Data System (ADS)

Seals, J. D.

The author reports on the design, material characteristics, and test results obtained under the US Air Force's advanced aircraft avionics packaging technologies (AAAPT) program, whose charter is to investigate new designs and technologies for reliable packaging, interconnection, and thermal management. Under this program, AT&T Bell Laboratories has completed the preliminary testing of and is evaluating a number of promising materials and technologies, including conformal encapsulation, liquid flow-through cooling, and a cyanate ester backplane. A fifty-two module system incorporating these and and other technologies has undergone preliminary cooling efficiency, shock, sine and random vibration, and maintenance testing. One of the primary objectives was to evaluate the interaction compatibility of new materials and designs with other components in the system.

Prototype solar heating and combined heating and cooling systems

NASA Technical Reports Server (NTRS)

1977-01-01

Eight prototype solar heating and combined heating and cooling systems are being developed. The effort includes development, manufacture, test, installation, maintenance, problem resolution, and performance evaluation.

Comparison of simulated and experimental results of temperature distribution in a closed two-phase thermosyphon cooling system

NASA Astrophysics Data System (ADS)

Shaanika, E.; Yamaguchi, K.; Miki, M.; Ida, T.; Izumi, M.; Murase, Y.; Oryu, T.; Yanamoto, T.

2017-12-01

Superconducting generators offer numerous advantages over conventional generators of the same rating. They are lighter, smaller and more efficient. Amongst a host of methods for cooling HTS machinery, thermosyphon-based cooling systems have been employed due to their high heat transfer rate and near-isothermal operating characteristics associated with them. To use them optimally, it is essential to study thermal characteristics of these cryogenic thermosyphons. To this end, a stand-alone neon thermosyphon cooling system with a topology resembling an HTS rotating machine was studied. Heat load tests were conducted on the neon thermosyphon cooling system by applying a series of heat loads to the evaporator at different filling ratios. The temperature at selected points of evaporator, adiabatic tube and condenser as well as total heat leak were measured. A further study involving a computer thermal model was conducted to gain further insight into the estimated temperature distribution of thermosyphon components and heat leak of the cooling system. The model employed boundary conditions from data of heat load tests. This work presents a comparison between estimated (by model) and experimental (measured) temperature distribution in a two-phase cryogenic thermosyphon cooling system. The simulation results of temperature distribution and heat leak compared generally well with experimental data.

Solar heating and cooling system design and development

NASA Technical Reports Server (NTRS)

1978-01-01

The progress made in the manufacture, test, evaluation, installation, problem resolution, performance evaluation, and development of eight prototype solar heating and combined heating and cooling systems is described.

Initial operation of a solar heating and cooling system in a full-scale solar building test facility

NASA Technical Reports Server (NTRS)

Knoll, R. H.; Miao, D.; Hamlet, I. L.; Jensen, R. N.

1976-01-01

The Solar Building Test Facility (SBTF) located at Hampton, Virginia became operational in early summer of 1976. This facility is a joint effort by NASA-Lewis and NASA-Langley to advance the technology for heating and cooling of office buildings with solar energy. Its purposes are to (1) test system components which include high-performing collectors, (2) test performance of complete solar heating and cooling system, (3) investigate component interactions and (4) investigate durability, maintenance and reliability of components. The SBTF consists of a 50,000 square foot office building modified to accept solar heated water for operation of an absorption air conditioner and for the baseboard heating system. A 12,666 square foot solar collector field with a 30,000 gallon storage tank provides the solar heated water. A description of the system and the collectors selected is given here, along with the objectives, test approach, expected system performance and some preliminary results.

KRESS INDIRECT DRY COOLING SYSTEM, BETHLEHEM STEEL'S COKE PLANT DEMONSTRATION AT SPARROWS POINT, MARYLAND - VOLUME 1. TECHNICAL REPORT AND APPENDICES A-F

EPA Science Inventory

The report evaluates the Kress Indirect Dry Cooling (KIDC) process, an innovative system for handling and cooling coke produced from a slot-type by-product coke oven battery. he report is based on the test work and demonstration of the system at Bethlehem Steel Corporation's Spar...

Conceptual Study on Hypersonic Turbojet Experimental Vehicle (HYTEX)

NASA Astrophysics Data System (ADS)

Taguchi, Hideyuki; Murakami, Akira; Sato, Tetsuya; Tsuchiya, Takeshi

Pre-cooled turbojet engines have been investigated aiming at realization of reusable space transportation systems and hypersonic airplanes. Evaluation methods of these engine performances have been established based on ground tests. There are some plans on the demonstration of hypersonic propulsion systems. JAXA focused on hypersonic propulsion systems as a key technology of hypersonic transport airplane. Demonstrations of Mach 5 class hypersonic technologies are stated as a development target at 2025 in the long term vision. In this study, systems analyses of hypersonic turbojet experiment (HYTEX) with Mach 5 flight capability is performed. Aerodynamic coefficients are obtained by CFD analyses and wind tunnel tests. Small Pre-cooled turbojet is fabricated and tested using liquid hydrogen as fuel. As a result, characteristics of the baseline vehicle shape is clarified, . and effects of pre-cooling are confirmed at the firing test.

Comprehensive Evaluation of Biological Growth Control by Chlorine-Based Biocides in Power Plant Cooling Systems Using Tertiary Effluent

PubMed Central

Chien, Shih-Hsiang; Dzombak, David A.; Vidic, Radisav D.

2013-01-01

Abstract Recent studies have shown that treated municipal wastewater can be a reliable cooling water alternative to fresh water. However, elevated nutrient concentration and microbial population in wastewater lead to aggressive biological proliferation in the cooling system. Three chlorine-based biocides were evaluated for the control of biological growth in cooling systems using tertiary treated wastewater as makeup, based on their biocidal efficiency and cost-effectiveness. Optimal chemical regimens for achieving successful biological growth control were elucidated based on batch-, bench-, and pilot-scale experiments. Biocide usage and biological activity in planktonic and sessile phases were carefully monitored to understand biological growth potential and biocidal efficiency of the three disinfectants in this particular environment. Water parameters, such as temperature, cycles of concentration, and ammonia concentration in recirculating water, critically affected the biocide performance in recirculating cooling systems. Bench-scale recirculating tests were shown to adequately predict the biocide residual required for a pilot-scale cooling system. Optimal residuals needed for proper biological growth control were 1, 2–3, and 0.5–1 mg/L as Cl2 for NaOCl, preformed NH2Cl, and ClO2, respectively. Pilot-scale tests also revealed that Legionella pneumophila was absent from these cooling systems when using the disinfectants evaluated in this study. Cost analysis showed that NaOCl is the most cost-effective for controlling biological growth in power plant recirculating cooling systems using tertiary-treated wastewater as makeup. PMID:23781129

Comprehensive Evaluation of Biological Growth Control by Chlorine-Based Biocides in Power Plant Cooling Systems Using Tertiary Effluent.

PubMed

Chien, Shih-Hsiang; Dzombak, David A; Vidic, Radisav D

2013-06-01

Recent studies have shown that treated municipal wastewater can be a reliable cooling water alternative to fresh water. However, elevated nutrient concentration and microbial population in wastewater lead to aggressive biological proliferation in the cooling system. Three chlorine-based biocides were evaluated for the control of biological growth in cooling systems using tertiary treated wastewater as makeup, based on their biocidal efficiency and cost-effectiveness. Optimal chemical regimens for achieving successful biological growth control were elucidated based on batch-, bench-, and pilot-scale experiments. Biocide usage and biological activity in planktonic and sessile phases were carefully monitored to understand biological growth potential and biocidal efficiency of the three disinfectants in this particular environment. Water parameters, such as temperature, cycles of concentration, and ammonia concentration in recirculating water, critically affected the biocide performance in recirculating cooling systems. Bench-scale recirculating tests were shown to adequately predict the biocide residual required for a pilot-scale cooling system. Optimal residuals needed for proper biological growth control were 1, 2-3, and 0.5-1 mg/L as Cl 2 for NaOCl, preformed NH 2 Cl, and ClO 2 , respectively. Pilot-scale tests also revealed that Legionella pneumophila was absent from these cooling systems when using the disinfectants evaluated in this study. Cost analysis showed that NaOCl is the most cost-effective for controlling biological growth in power plant recirculating cooling systems using tertiary-treated wastewater as makeup.

Solar residential heating and cooling system development test program

NASA Technical Reports Server (NTRS)

Humphries, W. R.; Melton, D. E.

1974-01-01

A solar heating and cooling system is described, which was installed in a simulated home at Marshall Space Flight Center. Performance data are provided for the checkout and initial operational phase for key subsystems and for the total system. Valuable information was obtained with regard to operation of a solar cooling system during the first summer of operation. Areas where improvements and modifications are required to optimize such a system are discussed.

Solar heating and cooling demonstration project at the Florida solar energy center

NASA Technical Reports Server (NTRS)

1980-01-01

The retrofitted solar heating and cooling system installed at the Florida Solar Energy Center is described. The system was designed to supply approximately 70 percent of the annual cooling and 100 percent of the heating load. The project provides unique high temperature, nonimaging, nontracking, evacuated tube collectors. The design of the system was kept simple and employs five hydronic loops. They are energy collection, chilled water production, space cooling, space heating and energy rejection. Information is provided on the system's acceptance test results operation, controls, hardware and installation, including detailed drawings.

The NASA-Lewis/ERDA Solar Heating and Cooling Technology Program

NASA Technical Reports Server (NTRS)

Couch, J. P.; Bloomfield, H. S.

1975-01-01

The NASA Lewis Research Center plans to carry out a major role in the ERDA Solar Heating and Cooling Program. This role would be to create and test the enabling technology for future solar heating, cooling, and combined heating/cooling systems. The major objectives of the project are to achieve reduction in solar energy system costs, while maintaining adequate performance, reliability, life, and maintenance characteristics. The project approach is to move progressively through component, subsystem, and then system technology advancement phases in parallel with continuing manufacturing cost assessment studies. This approach will be accomplished principally by contract with industry to develop advanced components and subsystems. This advanced hardware will be tested to establish 'technology readiness' both under controlled laboratory conditions and under real sun conditions.

A lab-based study of subground passive cooling system for indoor temperature control

NASA Astrophysics Data System (ADS)

Chok, Mun-Hong; Chan, Chee-Ming

2017-11-01

Passive cooling is an alternative cooling technique which helps to reduce high energy consumption. Respectively, dredged marine soil (DMS) is either being dumped or disposed as waste materials. Dredging works had resulted high labor cost, therefore reuse DMS as to fill it along the coastal area. In this study, DMS chosen to examine the effectiveness of passive cooling system by model tests. Soil characterization were carried out according to BS1377: Part 2: 1990. Model were made into scale of 3 cm to 1 m. Heat exchange unit consists of three pipe designs namely, parallel, ramp and spiral. Preliminary tests including flow rate test and soil sample selection were done to select the best heat exchange unit to carry out the model test. Model test is classified into 2 conditions, day and night, each condition consists of 4 configurations which the temperature results are determined. The result shows that window left open and fan switched on (WO/FO) recorded the most effective cooling effects, from 29 °C to 27 °C with drop of 6.9 %.

The NASA-Lewis/ERDA solar heating and cooling technology program. [project planning/energy policy

NASA Technical Reports Server (NTRS)

Couch, J. P.; Bloomfield, H. S.

1975-01-01

Plans by NASA to carry out a major role in a solar heating and cooling program are presented. This role would be to create and test the enabling technology for future solar heating, cooling, and combined heating/cooling systems. The major objectives of the project are to achieve reduction in solar energy system costs, while maintaining adequate performance, reliability, life, and maintenance characteristics. The project approach is discussed, and will be accomplished principally by contract with industry to develop advanced components and subsystems. Advanced hardware will be tested to establish 'technology readiness' both under controlled laboratory conditions and under real sun conditions.

Prototype solar heating and combined heating and cooling systems

NASA Technical Reports Server (NTRS)

1977-01-01

Schedules and technical progress in the development of eight prototype solar heating and combined solar heating and cooling systems are reported. Particular emphasis is given to the analysis and preliminary design for the cooling subsystem, and the setup and testing of a horizontal thermal energy storage tank configuration and collector shroud evaluation.

Prototype solar heating and cooling systems

NASA Technical Reports Server (NTRS)

1978-01-01

A collection of monthly status reports on the development of eight prototype solar heating and cooling systems is presented. The effort calls for the development, manufacture, test, system installation, maintenance, problem resolution, and performance evaluation. The systems are 3, 25, and 75 ton size units.

Prototype solar heating and cooling systems

NASA Technical Reports Server (NTRS)

1978-01-01

A collection of monthly status reports are given on the development of eight prototype solar heating and cooling systems. This effort calls for the development, manufacturing, test, system installation, maintenance, problem resolution, and performance evaluation. The systems are 3-, 25-, and 75-ton size units.

Liquid Hydrogen Recirculation System for Forced Flow Cooling Test of Superconducting Conductors

NASA Astrophysics Data System (ADS)

Shirai, Y.; Kainuma, T.; Shigeta, H.; Shiotsu, M.; Tatsumoto, H.; Naruo, Y.; Kobayashi, H.; Nonaka, S.; Inatani, Y.; Yoshinaga, S.

2017-12-01

The knowledge of forced flow heat transfer characteristics of liquid hydrogen (LH2) is important and necessary for design and cooling analysis of high critical temperature superconducting devices. However, there are few test facilities available for LH2 forced flow cooling for superconductors. A test system to provide a LH2 forced flow (∼10 m/s) of a short period (less than 100 s) has been developed. The test system was composed of two LH2 tanks connected by a transfer line with a controllable valve, in which the forced flow rate and its period were limited by the storage capacity of tanks. In this paper, a liquid hydrogen recirculation system, which was designed and fabricated in order to study characteristics of superconducting cables in a stable forced flow of liquid hydrogen for longer period, was described. This LH2 loop system consists of a centrifugal pump with dynamic gas bearings, a heat exchanger which is immersed in a liquid hydrogen tank, and a buffer tank where a test section (superconducting wires or cables) is set. The buffer tank has LHe cooled superconducting magnet which can produce an external magnetic field (up to 7T) at the test section. A performance test was conducted. The maximum flow rate was 43.7 g/s. The lowest temperature was 22.5 K. It was confirmed that the liquid hydrogen can stably circulate for 7 hours.

The development of a cryogenic over-pressure pump

NASA Astrophysics Data System (ADS)

Alvarez, M.; Cease, H.; Flaugher, B.; Flores, R.; Garcia, J.; Lathrop, A.; Ruiz, F.

2014-01-01

A cryogenic over-pressure pump (OPP) was tested in the prototype telescope liquid nitrogen (LN2) cooling system for the Dark Energy Survey (DES) Project. This OPP consists of a process cylinder (PC), gas generator, and solenoid operated valves (SOVs). It is a positive displacement pump that provided intermittent liquid nitrogen (LN2) flow to an array of charge couple devices (CCDs) for the prototype Dark Energy Camera (DECam). In theory, a heater submerged in liquid would generate the drive gas in a closed loop cooling system. The drive gas would be injected into the PC to displace that liquid volume. However, due to limitations of the prototype closed loop nitrogen system (CCD cooling system) for DECam, a quasiclosed-loop nitrogen system was created. During the test of the OPP, the CCD array was cooled to its designed set point temperature of 173K. It was maintained at that temperature via electrical heaters. The performance of the OPP was captured in pressure, temperature, and flow rate in the CCD LN2 cooling system at Fermi National Accelerator Laboratory (FNAL).

Development of ZL400 Mine Cooling Unit Using Semi-Hermetic Screw Compressor and Its Application on Local Air Conditioning in Underground Long-Wall Face

NASA Astrophysics Data System (ADS)

Chu, Zhaoxiang; Ji, Jianhu; Zhang, Xijun; Yan, Hongyuan; Dong, Haomin; Liu, Junjie

2016-12-01

Aiming at heat injuries occurring in the process of deep coal mining in China, a ZL400 mine-cooling unit employing semi-hermetic screw compressor with a cooling capacity of 400 kW is developed. This paper introduced its operating principle, structural characteristics and technical indexes. By using the self-built testing platform, some parameters for indication of its operation conditions were tested on the ground. The results show that the aforementioned cooling unit is stable in operation: cooling capacity of the unit was 420 kW underground-test conditions, while its COP (coefficient of performance) reached 3.4. To address the issue of heat injuries existing in No. 16305 U-shaped long-wall ventilation face of Jining No. 3 coal mine, a local air conditioning system was developed with ZL400 cooling unit as the system's core. The paper presented an analysis of characteristics of the air current flowing in the air-mixing and cooling mode of ZL400 cooling unit used in air intake way. Through i-d patterns we described the process of the airflow treatment, such as cooling, mixing and heating, etc. The cooling system decreased dry bulb temperature on working face by 3°C on average and 3.8°C at most, while lowered the web bulb temperature by 3.6°C on average and 4.8°C at most. At the same time, it reduced relative humidity by 5% on average and 8.6% at most. The field application of the ZL400 cooling unit had gain certain effects in air conditioning and provided support for the solution of mine heat injuries in China in terms of technology and equipment.

New Technique for Cryogenically Cooling Small Test Articles

NASA Technical Reports Server (NTRS)

Rodriquez, Karen M.; Henderson, Donald J.

2011-01-01

Convective heat removal techniques to rapidly cool small test articles to Earth-Moon L2 temperatures of 77 K were accomplished through the use of liquid nitrogen (LN2). By maintaining a selected pressure range on the saturation curve, test articles were cooled below the LN2 boiling point at ambient pressure in less than 30 min. Difficulties in achieving test pressures while maintaining the temperature tolerance necessitated a modification to the original system to include a closed loop conductive cold plate and cryogenic shroud

Critical Current Test of Liquid Hydrogen Cooled HTC Superconductors under External Magnetic Field

NASA Astrophysics Data System (ADS)

Shirai, Yasuyuki; Shiotsu, Masahiro; Tatsumoto, Hideki; Kobayashi, Hiroaki; Naruo, Yoshihiro; Nonaka, Satoshi; Inatani, Yoshifumi

High-Tc (HTC) superconductors including MgB2 will show excellent properties under temperature of Liquid Hydrogen (LH2:20K), which has large latent heat and low viscosity coefficient. In order to design and fabricate the LH2 cooled superconducting energy devices, we must clear the cooling property of LH2 for superconductors, the cooling system and safety design of LH2 cooled superconducting devices and electro-magnetic property evaluation of superconductors (BSCCO, REBCO and MgB2) and their magnets cooled by LH2. As the first step of the study, an experimental setup which can be used for investigating heat transfer characteristics of LH2 in a pool and also in forced flow (circulation loop with a pump), and also for evaluation of electro-magnetic properties of LH2 cooled superconductors under external magnetic field (up to 7 T). In this paper, we will show a short sketch of the experimental set-up, practical experiences in safety operation of liquid hydrogen cooling system and example test results of critical current evaluation of HTC superconductors cooled by LH2.

Solid cryogen: a cooling system for future MgB2 MRI magnet

PubMed Central

Patel, Dipak; Hossain, Md Shahriar Al; Qiu, Wenbin; Jie, Hyunseock; Yamauchi, Yusuke; Maeda, Minoru; Tomsic, Mike; Choi, Seyong; Kim, Jung Ho

2017-01-01

An efficient cooling system and the superconducting magnet are essential components of magnetic resonance imaging (MRI) technology. Herein, we report a solid nitrogen (SN2) cooling system as a valuable cryogenic feature, which is targeted for easy usability and stable operation under unreliable power source conditions, in conjunction with a magnesium diboride (MgB2) superconducting magnet. The rationally designed MgB2/SN2 cooling system was first considered by conducting a finite element analysis simulation, and then a demonstrator coil was empirically tested under the same conditions. In the SN2 cooling system design, a wide temperature distribution on the SN2 chamber was observed due to the low thermal conductivity of the stainless steel components. To overcome this temperature distribution, a copper flange was introduced to enhance the temperature uniformity of the SN2 chamber. In the coil testing, an operating current as high as 200 A was applied at 28 K (below the critical current) without any operating or thermal issues. This work was performed to further the development of SN2 cooled MgB2 superconducting coils for MRI applications. PMID:28251984

Residential solar-heating/cooling system

NASA Technical Reports Server (NTRS)

1980-01-01

Report documents progress of residential solar-heating and cooling system development program at 5-month mark of anticipated 17-month program. System design has been completed, and development and component testing has been initiated. Report includes diagrams, operation overview, optimization studies of subcomponents, and marketing plans for system.

Industrial and biomedical use of aerospace personal cooling garments

NASA Technical Reports Server (NTRS)

Williams, B. A.; Mcewen, G. N., Jr.; Montgomery, L. D.; Elkins, W. E.

1975-01-01

Liquid-cooled garments (LCG) have been developed which utilize liquid-cooled modules rather than the network of tygon tubing typical of Apollo LCG's. The ultra-thin, heat-sealed, polyurethane modules are situated over the body to cover 50 percent of the body surface area with special emphasis on the 'working' muscles and the head-neck area. These garments are being designed specifically for industrial and biomedical uses, such as: a head-neck cooling system which is being tested for race-car drivers, tractor drivers, truck drivers, or a head-neck cooling system tested for the reduction of the scalp hair loss which normally accompanies cancer treatments. A combined head-neck and thorax unit is being developed for use during mine distaster rescue operations, and for other hazardous hot applications. Finally applications for head-neck and partitional cooling are anticipated for military pilots, tank drivers, and heavy equipment operations.

Thermally Simulated 32kW Direct-Drive Gas-Cooled Reactor: Design, Assembly, and Test

NASA Astrophysics Data System (ADS)

Godfroy, Thomas J.; Kapernick, Richard J.; Bragg-Sitton, Shannon M.

2004-02-01

One of the power systems under consideration for nuclear electric propulsion is a direct-drive gas-cooled reactor coupled to a Brayton cycle. In this system, power is transferred from the reactor to the Brayton system via a circulated closed loop gas. To allow early utilization, system designs must be relatively simple, easy to fabricate, and easy to test using non-nuclear heaters to closely mimic heat from fission. This combination of attributes will allow pre-prototypic systems to be designed, fabricated, and tested quickly and affordably. The ability to build and test units is key to the success of a nuclear program, especially if an early flight is desired. The ability to perform very realistic non-nuclear testing increases the success probability of the system. In addition, the technologies required by a concept will substantially impact the cost, time, and resources required to develop a successful space reactor power system. This paper describes design features, assembly, and test matrix for the testing of a thermally simulated 32kW direct-drive gas-cooled reactor in the Early Flight Fission - Test Facility (EFF-TF) at Marshall Space Flight Center. The reactor design and test matrix are provided by Los Alamos National Laboratories.

First Principles Modeling of RFQ Cooling System and Resonant Frequency Responses for Fermilab’s PIP-II Injector Test

DOE PAGES

Edelen, J. P.; Edelen, A. L.; Bowring, D.; ...

2016-12-23

In this study we develop an a priori method for simulating dynamic resonant frequency and temperature responses in a radio frequency quadrupole (RFQ) and its associated water-based cooling system respectively. Our model provides a computationally efficient means to evaluate the transient response of the RFQ over a large range of system parameters. The model was constructed prior to the delivery of the PIP-II Injector Test RFQ and was used to aid in the design of the water-based cooling system, data acquisition system, and resonance control system. Now that the model has been validated with experimental data, it can confidently bemore » used to aid in the design of future RFQ resonance controllers and their associated water-based cooling systems. Finally, without any empirical fitting, it has demonstrated the ability to predict absolute temperature and frequency changes to 11% accuracy on average, and relative changes to 7% accuracy.« less

Development of a prototype thermoelectric space cooling system using phase change material to improve the performance

NASA Astrophysics Data System (ADS)

Zhao, Dongliang

The thermoelectric cooling system has advantages over conventional vapor compression cooling devices, including compact in size, light in weight, high reliability, no mechanical moving parts, no refrigerant, being powered by direct current, and easily switching between cooling and heating modes. However, it has been long suffering from its relatively high cost and low energy efficiency, which has restricted its usage to niche applications, such as space missions, portable cooling devices, scientific and medical equipment, where coefficient of performance (COP) is not as important as reliability, energy availability, and quiet operation environment. Enhancement of thermoelectric cooling system performance generally relies on two methods: improving thermoelectric material efficiency and through thermoelectric cooling system thermal design. This research has been focused on the latter one. A prototype thermoelectric cooling system integrated with phase change material (PCM) thermal energy storage unit for space cooling has been developed. The PCM thermal storage unit used for cold storage at night, functions as the thermoelectric cooling system's heat sink during daytime's cooling period and provides relatively lower hot side temperature for the thermoelectric cooling system. The experimental test of the prototype system in a reduced-scale chamber has realized an average cooling COP of 0.87, with the maximum value of 1.22. Another comparison test for efficacy of PCM thermal storage unit shows that 35.3% electrical energy has been saved from using PCM for the thermoelectric cooling system. In general, PCM faces difficulty of poor thermal conductivity at both solid and liquid phases. This system implemented a finned inner tube to increase heat transfer during PCM charging (melting) process that directly impacts thermoelectric system's performance. A simulation tool for the entire system has been developed including mathematical models for a single thermoelectric module, for the thermoelectric cooling unit, for the PCM thermal storage unit, and for the outdoor air-water heat exchanger. When modeling PCM thermal storage unit, the enthalpy method has been adopted. Since natural convection has been observed in experiments playing a key effect on heat transfer in PCM, a staged effective thermal conductivity (ke) concept and modified Rayleigh (Ra) number formula have been developed to better capture natural convection's variable effects during the PCM charging process. Therefore, a modeling-based design procedure for thermoelectric cooling system integrating with PCM has been proposed. A case study has been completed for a model office room to demonstrate the qualitative and quantitative evaluations to the major system components. Results of this research can be extended to other applications in relevant areas. For instance, the proposed PCM thermal storage unit can be applied to integration with water-cooled conventional air-conditioning devices. Instead of using water cooling, a case study of using the proposed PCM unit for a water-cooled air-conditioner shows a COP increase of more than 25.6%.

Cooled Ceramic Matrix Composite Propulsion Structures Demonstrated

NASA Technical Reports Server (NTRS)

Jaskowiak, Martha H.; Dickens, Kevin W.

2005-01-01

NASA's Next Generation Launch Technology (NGLT) Program has successfully demonstrated cooled ceramic matrix composite (CMC) technology in a scramjet engine test. This demonstration represented the world s largest cooled nonmetallic matrix composite panel fabricated for a scramjet engine and the first cooled nonmetallic composite to be tested in a scramjet facility. Lightweight, high-temperature, actively cooled structures have been identified as a key technology for enabling reliable and low-cost space access. Tradeoff studies have shown this to be the case for a variety of launch platforms, including rockets and hypersonic cruise vehicles. Actively cooled carbon and CMC structures may meet high-performance goals at significantly lower weight, while improving safety by operating with a higher margin between the design temperature and material upper-use temperature. Studies have shown that using actively cooled CMCs can reduce the weight of the cooled flow-path component from 4.5 to 1.6 lb/sq ft and the weight of the propulsion system s cooled surface area by more than 50 percent. This weight savings enables advanced concepts, increased payload, and increased range. The ability of the cooled CMC flow-path components to operate over 1000 F hotter than the state-of-the-art metallic concept adds system design flexibility to space-access vehicle concepts. Other potential system-level benefits include smaller fuel pumps, lower part count, lower cost, and increased operating margin.

Application of reliability-centered maintenance to boiling water reactor emergency core cooling systems fault-tree analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Y.A.; Feltus, M.A.

1995-07-01

Reliability-centered maintenance (RCM) methods are applied to boiling water reactor plant-specific emergency core cooling system probabilistic risk assessment (PRA) fault trees. The RCM is a technique that is system function-based, for improving a preventive maintenance (PM) program, which is applied on a component basis. Many PM programs are based on time-directed maintenance tasks, while RCM methods focus on component condition-directed maintenance tasks. Stroke time test data for motor-operated valves (MOVs) are used to address three aspects concerning RCM: (a) to determine if MOV stroke time testing was useful as a condition-directed PM task; (b) to determine and compare the plant-specificmore » MOV failure data from a broad RCM philosophy time period compared with a PM period and, also, compared with generic industry MOV failure data; and (c) to determine the effects and impact of the plant-specific MOV failure data on core damage frequency (CDF) and system unavailabilities for these emergency systems. The MOV stroke time test data from four emergency core cooling systems [i.e., high-pressure coolant injection (HPCI), reactor core isolation cooling (RCIC), low-pressure core spray (LPCS), and residual heat removal/low-pressure coolant injection (RHR/LPCI)] were gathered from Philadelphia Electric Company`s Peach Bottom Atomic Power Station Units 2 and 3 between 1980 and 1992. The analyses showed that MOV stroke time testing was not a predictor for eminent failure and should be considered as a go/no-go test. The failure data from the broad RCM philosophy showed an improvement compared with the PM-period failure rates in the emergency core cooling system MOVs. Also, the plant-specific MOV failure rates for both maintenance philosophies were shown to be lower than the generic industry estimates.« less

The development of a solar-powered residential heating and cooling system

NASA Technical Reports Server (NTRS)

1974-01-01

Efforts to demonstrate the engineering feasibility of utilizing solar power for residential heating and cooling are described. These efforts were concentrated on the analysis, design, and test of a full-scale demonstration system which is currently under construction at the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville, Alabama. The basic solar heating and cooling system under development utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating and water heating, and an absorption cycle air conditioner for space cooling.

Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation

PubMed Central

Schmidt, Marvin; Ullrich, Johannes; Wieczorek, André; Frenzel, Jan; Eggeler, Gunther; Schütze, Andreas; Seelecke, Stefan

2016-01-01

Shape Memory Alloys (SMA) using elastocaloric cooling processes have the potential to be an environmentally friendly alternative to the conventional vapor compression based cooling process. Nickel-Titanium (Ni-Ti) based alloy systems, especially, show large elastocaloric effects. Furthermore, exhibit large latent heats which is a necessary material property for the development of an efficient solid-state based cooling process. A scientific test rig has been designed to investigate these processes and the elastocaloric effects in SMAs. The realized test rig enables independent control of an SMA's mechanical loading and unloading cycles, as well as conductive heat transfer between SMA cooling elements and a heat source/sink. The test rig is equipped with a comprehensive monitoring system capable of synchronized measurements of mechanical and thermal parameters. In addition to determining the process-dependent mechanical work, the system also enables measurement of thermal caloric aspects of the elastocaloric cooling effect through use of a high-performance infrared camera. This combination is of particular interest, because it allows illustrations of localization and rate effects — both important for efficient heat transfer from the medium to be cooled. The work presented describes an experimental method to identify elastocaloric material properties in different materials and sample geometries. Furthermore, the test rig is used to investigate different cooling process variations. The introduced analysis methods enable a differentiated consideration of material, process and related boundary condition influences on the process efficiency. The comparison of the experimental data with the simulation results (of a thermomechanically coupled finite element model) allows for better understanding of the underlying physics of the elastocaloric effect. In addition, the experimental results, as well as the findings based on the simulation results, are used to improve the material properties. PMID:27168093

Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation.

PubMed

Schmidt, Marvin; Ullrich, Johannes; Wieczorek, André; Frenzel, Jan; Eggeler, Gunther; Schütze, Andreas; Seelecke, Stefan

2016-05-02

Shape Memory Alloys (SMA) using elastocaloric cooling processes have the potential to be an environmentally friendly alternative to the conventional vapor compression based cooling process. Nickel-Titanium (Ni-Ti) based alloy systems, especially, show large elastocaloric effects. Furthermore, exhibit large latent heats which is a necessary material property for the development of an efficient solid-state based cooling process. A scientific test rig has been designed to investigate these processes and the elastocaloric effects in SMAs. The realized test rig enables independent control of an SMA's mechanical loading and unloading cycles, as well as conductive heat transfer between SMA cooling elements and a heat source/sink. The test rig is equipped with a comprehensive monitoring system capable of synchronized measurements of mechanical and thermal parameters. In addition to determining the process-dependent mechanical work, the system also enables measurement of thermal caloric aspects of the elastocaloric cooling effect through use of a high-performance infrared camera. This combination is of particular interest, because it allows illustrations of localization and rate effects - both important for efficient heat transfer from the medium to be cooled. The work presented describes an experimental method to identify elastocaloric material properties in different materials and sample geometries. Furthermore, the test rig is used to investigate different cooling process variations. The introduced analysis methods enable a differentiated consideration of material, process and related boundary condition influences on the process efficiency. The comparison of the experimental data with the simulation results (of a thermomechanically coupled finite element model) allows for better understanding of the underlying physics of the elastocaloric effect. In addition, the experimental results, as well as the findings based on the simulation results, are used to improve the material properties.

Advanced Space Suit PLSS 2.0 Cooling Loop Evaluation and PLSS 2.5 Recommendations

NASA Technical Reports Server (NTRS)

Steele, John; Quinn, Greg; Campbell, Colin; Makinen, Janice; Watts, Carly; Westheimer, Dave

2016-01-01

From 2012 to 2015 The NASA/JSC AdvSS (Advanced Space Suit) PLSS (Primary Life Support Subsystem) team, with support from UTC Aerospace Systems, performed the build-up, packaging and testing of PLSS 2.0. A key aspect of that testing was the evaluation of the long-term health of the water cooling circuit and the interfacing components. Intermittent and end-of-test water, residue and hardware analyses provided valuable information on the status of the water cooling circuit, and the approaches that would be necessary to enhance water cooling circuit health in the future. The evaluated data has been consolidated, interpreted and woven into an action plan for the maintenance of water cooling circuit health for the planned FY (fiscal year) 2016 through FY 2018 PLSS 2.5 testing. This paper provides an overview of the PLSS 2.0 water cooling circuit findings and the associated steps to be taken in that regard for the PLSS 2.5 testing.

Temperature Controller System for Gas Gun Targets

NASA Astrophysics Data System (ADS)

Bucholtz, S. M.; Gehr, R. J.; Rupp, T. D.; Sheffield, S. A.; Robbins, D. L.

2006-07-01

A temperature controller system capable of heating and cooling gas gun targets over the range -75°C to +120°C was designed and tested. The system uses cold nitrogen gas from a liquid nitrogen Dewar for cooling and compressed air for heating. Two gas flow heaters control the gas temperature for both heating and cooling. One heater controls the temperature of the target mounting plate and the other the temperature of a copper tubing coil surrounding the target. Each heater is separately adjustable, so the target material will achieve a uniform temperature throughout its volume. A magnetic gauge membrane with integrated thermocouples was developed to measure the internal temperature of the target. Using this system, multiple magnetic gauge shock experiments, including equation-of-state measurements and shock initiation of high explosives, can be performed over a range of initial temperatures. Successful heating and cooling tests were completed on Teflon samples.

Qualification test and analysis report: Solar collectors

NASA Technical Reports Server (NTRS)

1978-01-01

Test results show that the Owens-Illinois Sunpak TM Model SEC 601 air-cooled collector meets the national standards and codes as defined in the Subsystem Peformance Specification and Verification Plan of NASA/MSFC, dated October 28, 1976. The program calls for the development, fabrication, qualification and delivery of an air-cooled solar collector for solar heating, combined heating and cooling, and/or hot water systems.

James Webb Space Telescope Core 2 Test - Cryogenic Thermal Balance Test of the Observatorys Core Area Thermal Control Hardware

NASA Technical Reports Server (NTRS)

Cleveland, Paul; Parrish, Keith; Thomson, Shaun; Marsh, James; Comber, Brian

2016-01-01

The James Webb Space Telescope (JWST), successor to the Hubble Space Telescope, will be the largest astronomical telescope ever sent into space. To observe the very first light of the early universe, JWST requires a large deployed 6.5-meter primary mirror cryogenically cooled to less than 50 Kelvin. Three scientific instruments are further cooled via a large radiator system to less than 40 Kelvin. A fourth scientific instrument is cooled to less than 7 Kelvin using a combination pulse-tube Joule-Thomson mechanical cooler. Passive cryogenic cooling enables the large scale of the telescope which must be highly folded for launch on an Ariane 5 launch vehicle and deployed once on orbit during its journey to the second Earth-Sun Lagrange point. Passive cooling of the observatory is enabled by the deployment of a large tennis court sized five layer Sunshield combined with the use of a network of high efficiency radiators. A high purity aluminum heat strap system connects the three instrument's detector systems to the radiator systems to dissipate less than a single watt of parasitic and instrument dissipated heat. JWST's large scale features, while enabling passive cooling, also prevent the typical flight configuration fully-deployed thermal balance test that is the keystone of most space missions' thermal verification plans. This paper describes the JWST Core 2 Test, which is a cryogenic thermal balance test of a full size, high fidelity engineering model of the Observatory's 'Core' area thermal control hardware. The 'Core' area is the key mechanical and cryogenic interface area between all Observatory elements. The 'Core' area thermal control hardware allows for temperature transition of 300K to approximately 50 K by attenuating heat from the room temperature IEC (instrument electronics) and the Spacecraft Bus. Since the flight hardware is not available for test, the Core 2 test uses high fidelity and flight-like reproductions.

Development of a single-phase thermosiphon for cold collection and storage of radiative cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Dongliang; Martini, Christine Elizabeth; Jiang, Siyu

A single-phase thermosiphon is developed for cold collection and storage of radiative cooling. Compared to the conventional nocturnal radiative cooling systems that use an electric pump to drive the heat transfer fluid, the proposed single-phase thermosiphon uses the buoyancy force to drive heat transfer fluid. This solution does not require electricity, therefore improving the net gain of the radiative cooling system. A single-phase thermosiphon was built, which consists of a flat panel, a cold collection tank, a water return tube, and a water distribution tank. Considering that outdoor radiative cooling flux is constantly changing (i.e. uncontrollable), an indoor testing facilitymore » was developed to provide a controllable cooling flux (comparable to a radiative cooling flux of 100 W/m2) for the evaluation of thermosiphon performance. The testing apparatus is a chilled aluminum flat plate that has a controlled air gap separation relative to the flat panel surface of the thermosiphon to emulate radiative cooling. With an average of 105 W/m2 cooling flux, the 18 liters of water in the thermosiphon was cooled to an average temperature of 12.5 degrees C from an initial temperature of 22.2 degrees C in 2 h, with a cold collection efficiency of 96.8%. The results obtained have demonstrated the feasibility of using a single-phase thermosiphon for cold collection and storage of radiative cooling. Additionally, the effects of the thermosiphon operation conditions, such as tilt angle of the flat panel, initial water temperature, and cooling energy flux, on the performance have been experimentally investigated. Modular design of the single-phase thermosiphon gives flexibility for its scalability. A radiative cooling system with multiple thermosiphon modules is expected to play an important role in cooling buildings and power plant condensers.« less

Cryocooler based test setup for high current applications

NASA Astrophysics Data System (ADS)

Pradhan, Jedidiah; Das, Nisith Kr.; Roy, Anindya; Duttagupta, Anjan

2018-04-01

A cryo-cooler based cryogenic test setup has been designed, fabricated, and tested. The setup incorporates two numbers of cryo-coolers, one for sample cooling and the other one for cooling the large magnet coil. The performance and versatility of the setup has been tested using large samples of high-temperature superconductor magnet coil as well as short samples with high current. Several un-calibrated temperature sensors have been calibrated using this system. This paper presents the details of the system along with results of different performance tests.

Thermal modeling in an engine cooling system to control coolant flow for fuel consumption improvement

NASA Astrophysics Data System (ADS)

Park, Sangki; Woo, Seungchul; Kim, Minho; Lee, Kihyung

2017-04-01

The design and evaluation of engine cooling and lubrication systems is generally based on real vehicle tests. Our goal here was to establish an engine heat balance model based on mathematical and interpretive analysis of each element of a passenger diesel engine cooling system using a 1-D numerical model. The purpose of this model is to determine ways of optimizing the cooling and lubrication components of an engine and then to apply these methods to actual cooling and lubrication systems of engines that will be developed in the future. Our model was operated under the New European Driving Cycle (NEDC) mode conditions, which represent the fuel economy evaluation mode in Europe. The flow rate of the cooling system was controlled using a control valve. Our results showed that the fuel efficiency was improved by as much as 1.23 %, cooling loss by 1.35 %, and friction loss by 2.21 % throughout NEDC modes by modification of control conditions.

Biomedical Application of Aerospace Personal Cooling Systems

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Webbon, Bruce W.; Kliss, Mark (Technical Monitor)

1997-01-01

Personal thermoregulatory systems which are used by astronauts to alleviate thermal stress during extravehicular activity have been applied to the therapeutic management of multiple sclerosis. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to compare the effectiveness of two passive and two active cooling vests and to measure the body temperature and circulatory changes produced by each cooling vest configuration. The MicroClimate Systems and the Life Enhancement Tech(LET) lightweight liquid cooling vests, the Steele Vest and LET's Zipper Front Garment were used to cool the chest region of 10 male and female subjects (25 to 55 yr.) in this study. Calf, forearm and finger blood flows were measured using a tetrapolar impedance rheograph. The subjects, seated in an upright position at normal room temperature (approx.22C), were tested for 60 min. with the cooling system operated at its maximum cooling capacity. Blood flows were recorded continuously using a computer data acquisition system with a sampling frequency of 250 Hz. Oral, right and left ear temperatures and cooling system parameters were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; respiration; and an activity index were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. In general, the male and female subjects' oral and ear temperature responses to cooling were similar for all vest configurations tested. Oral temperatures during the recovery period were significantly (P<0.05) lower than during the control period, approx. 0.2 - 0.5C, for both men and women wearing any of the four different garments. The corresponding ear temperatures were significantly (P<0.05) decreased approx.0.2 - 0.4C by the end of the recovery period. Compared to the control period, no significant differences were found in rectal temperatures during cooling and recovery periods.

Demonstration of Passive Fuel Cell Thermal Management Technology

NASA Technical Reports Server (NTRS)

Burke, Kenneth A.; Jakupca, Ian; Colozza, Anthony; Wynne, Robert; Miller, Michael; Meyer, Al; Smith, William

2012-01-01

The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates and integrated heat exchanger technology to collect the heat from the cooling plates (Ref. 1). The next step in the development of this passive thermal approach was the demonstration of the control of the heat removal process and the demonstration of the passive thermal control technology in actual fuel cell stacks. Tests were run with a simulated fuel cell stack passive thermal management system outfitted with passive cooling plates, an integrated heat exchanger and two types of cooling flow control valves. The tests were run to demonstrate the controllability of the passive thermal control approach. Finally, successful demonstrations of passive thermal control technology were conducted with fuel cell stacks from two fuel cell stack vendors.

Routine sampling and the control of Legionella spp. in cooling tower water systems.

PubMed

Bentham, R H

2000-10-01

Cooling water samples from 31 cooling tower systems were cultured for Legionella over a 16-week summer period. The selected systems were known to be colonized by Legionella. Mean Legionella counts and standard deviations were calculated and time series correlograms prepared for each system. The standard deviations of Legionella counts in all the systems were very large, indicating great variability in the systems over the time period. Time series analyses demonstrated that in the majority of cases there was no significant relationship between the Legionella counts in the cooling tower at time of collection and the culture result once it was available. In the majority of systems (25/28), culture results from Legionella samples taken from the same systems 2 weeks apart were not statistically related. The data suggest that determinations of health risks from cooling towers cannot be reliably based upon single or infrequent Legionella tests.

Development and Experimental Evaluation of Passive Fuel Cell Thermal Control

NASA Technical Reports Server (NTRS)

Colozza, Anthony J.; Jakupca, Ian J.; Castle, Charles H.; Burke, Kenneth A.

2014-01-01

To provide uniform cooling for a fuel cell stack, a cooling plate concept was evaluated. This concept utilized thin cooling plates to extract heat from the interior of a fuel cell stack and move this heat to a cooling manifold where it can be transferred to an external cooling fluid. The advantages of this cooling approach include a reduced number of ancillary components and the ability to directly utilize an external cooling fluid loop for cooling the fuel cell stack. A number of different types of cooling plates and manifolds were developed. The cooling plates consisted of two main types; a plate based on thermopyrolytic graphite (TPG) and a planar (or flat plate) heat pipe. The plates, along with solid metal control samples, were tested for both thermal and electrical conductivity. To transfer heat from the cooling plates to the cooling fluid, a number of manifold designs utilizing various materials were devised, constructed, and tested. A key aspect of the manifold was that it had to be electrically nonconductive so it would not short out the fuel cell stack during operation. Different manifold and cooling plate configurations were tested in a vacuum chamber to minimize convective heat losses. Cooling plates were placed in the grooves within the manifolds and heated with surface-mounted electric pad heaters. The plate temperature and its thermal distribution were recorded for all tested combinations of manifold cooling flow rates and heater power loads. This testing simulated the performance of the cooling plates and manifold within an operational fuel cell stack. Different types of control valves and control schemes were tested and evaluated based on their ability to maintain a constant temperature of the cooling plates. The control valves regulated the cooling fluid flow through the manifold, thereby controlling the heat flow to the cooling fluid. Through this work, a cooling plate and manifold system was developed that could maintain the cooling plates within a minimal temperature band with negligible thermal gradients over power profiles that would be experienced within an operating fuel cell stack.

Passive wall cooling panel with phase change material as a cooling agent

NASA Astrophysics Data System (ADS)

Majid, Masni A.; Tajudin, Rasyidah Ahmad; Salleh, Norhafizah; Hamid, Noor Azlina Abd

2017-11-01

The study was carried out to the determine performance of passive wall cooling panels by using Phase Change Materials as a cooling agent. This passive cooling system used cooling agent as natural energy storage without using any HVAC system. Eight full scale passive wall cooling panels were developed with the size 1500 mm (L) × 500 mm (W) × 100 mm (T). The cooling agent such as glycerine were filled in the tube with horizontal and vertical arrangement. The passive wall cooling panels were casting by using foamed concrete with density between 1200 kg/m3 - 1500 kg/m3. The passive wall cooling panels were tested in a small house and the differences of indoor and outdoor temperature was recorded. Passive wall cooling panels with glycerine as cooling agent in vertical arrangement showed the best performance with dropped of indoor air temperature within 3°C compared to outdoor air temperature. The lowest indoor air temperature recorded was 25°C from passive wall cooling panels with glycerine in vertical arrangement. From this study, the passive wall cooling system could be applied as it was environmental friendly and less maintenance.

Inhibitor analysis for a solar heating and cooling system

NASA Technical Reports Server (NTRS)

Tabony, J. H.

1977-01-01

A study of potential corrosion inhibitors for the NASA solar heating and cooling system which uses aluminum solar panels is provided. Research consisted of testing using a dynamic corrosion system, along with an economic analysis of proposed corrosion inhibitors. Very good progress was made in finding a suitable inhibitor for the system.

Aerodynamic and Acoustic Tests of a 1/15 Scale Model Dry Cooled Jet Aircraft Runup Noise Suppression System,

DTIC Science & Technology

1975-10-01

sophisticated wet-cooled systems having scrubbers and their associated water treatment facilities . The United States Navy has recognized these Hush... venturi meter air inlet to measure the pumped air flow and the exhaust enclosure is provided with suitable ports for the flow to exit. The test program...constantan thermo- couple and venturi flow meters were used to measure the aerodynamic/thermo- dynamic information required from the tests (pressure

Solar heating and cooling system design and development

NASA Technical Reports Server (NTRS)

1979-01-01

The design and development of marketable solar heating and cooling systems for single family and commercial applications is described. The delivery, installation, and monitoring of the prototype systems are discussed. Seven operational test sites are discussed in terms of system performance. Problems encountered with equipment and installation were usually due to lack of skills required for solar system installation.

Broad Area Cooler Concepts for Cryogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Christie, R. J.; Tomsik, T. M.; Elchert, J. P.; Guzik, M. C.

2011-01-01

Numerous studies and ground tests have shown that broad area cooling (also known as distributed cooling) can reduce or eliminate cryogenic propellant boil-off and enable long duration storage in space. Various combinations of cryocoolers, circulators, heat exchangers and other hardware could be used to build the system. In this study, several configurations of broad area cooling systems were compared by weighing hardware combinations, input power requirements, component availability, and Technical Readiness Level (TRL). The preferred system has a high TRL and can be scaled up to provide cooling capacities on the order of 150W at 90K

Sub-ambient non-evaporative fluid cooling with the sky

NASA Astrophysics Data System (ADS)

Goldstein, Eli A.; Raman, Aaswath P.; Fan, Shanhui

2017-09-01

Cooling systems consume 15% of electricity generated globally and account for 10% of global greenhouse gas emissions. With demand for cooling expected to grow tenfold by 2050, improving the efficiency of cooling systems is a critical part of the twenty-first-century energy challenge. Building upon recent demonstrations of daytime radiative sky cooling, here we demonstrate fluid cooling panels that harness radiative sky cooling to cool fluids below the air temperature with zero evaporative losses, and use almost no electricity. Over three days of testing, we show that the panels cool water up to 5 ∘C below the ambient air temperature at water flow rates of 0.2 l min-1 m-2, corresponding to an effective heat rejection flux of up to 70 W m-2. We further show through modelling that, when integrated on the condenser side of the cooling system of a two-storey office building in a hot dry climate (Las Vegas, USA), electricity consumption for cooling during the summer could be reduced by 21% (14.3 MWh).

Physiological tolerance to uncompensated heat stress in soldiers: effects of various types of body cooling systems.

PubMed

Jovanović, Dalibor; Karkalić, Radovan; Zeba, Snjezana; Pavlović, Miroslav; Radaković, Sonja S

2014-03-01

In military services, emergency situations when soldiers are exposed to a combination of nuclear, biological and chemical (NBC) contamination combined with heat stress, are frequent and complex. In these specific conditions, usage of personal body cooling systems may be effective in reducing heat stress. The present study was conducted in order to evaluate the efficiency of four various types of contemporary personal body cooling systems based on the "Phase Change Material" (PCM), and its effects on soldiers' subjective comfort and physiological performance during exertional heat stress in hot environments. Ten male soldiers were voluntarily subjected to exertional heat stress tests (EHSTs) consisted of walking on a treadmill (5.5 km/h) in hot conditions (40 degreesC) in climatic chamber, wearing NBC isolating impermeable protective suits. One of the tests was performed without any additional cooling solution (NOCOOL), and four tests were performed while using different types of cooling systems: three in a form of vests and one as underwear. Physiological strain was determined by the mean skin temperature (Tsk), tympanic temperature (Tty), and heart rate values (HR), while sweat rates (SwR) indicated changes in hydration status. In all the cases EHST induced physiological response manifested through increasing Tty, HR and SwR. Compared to NOCOOL tests, when using cooling vests, Tty and Tsk were significantly lower (on 35th min, for 0.44 +/- 0.03 and 0.49 +/- 0.05 degrees C, respectively; p < 0.05), as well as the average SwR (0.17 +/- 0.03 L/m2/h). When using underwear, the values of given parameters were not significantly different compared to NOCOOL tests. Using a body cooling system based on PCM in the form of vest under NBC protective clothes during physical activity in hot conditions, reduces sweating and alleviates heat stress manifested by increased core and skin temperatures and heart rate values. These effects directly improve heat tolerance, hydration state, decrease in the risk of heat illness, and extends the duration of soldiers' exposure to extreme conditions.

Cryogenic System for J-Parc Neutrino Superconducting Magnet Beam LINE—DESIGN, Construction and Performance Test

NASA Astrophysics Data System (ADS)

Makida, Y.; Ohhata, H.; Okamura, T.; Suzuki, S.; Araoka, O.; Ogitsu, T.; Kimura, N.; Nakamoto, T.; Sasaki, K.; Kaneda, S.; Takahashi, T.; Ito, A.; Nagami, M.; Kumaki, T.; Nakashima, T.

2010-04-01

A helium cryogenic plant has been constructed in the proton accelerator research complex, J-PARC, to cool a string of superconducting magnets in the neutrino beam line since 2005. It consists of a screw compressor with a capacity of 160 g/s at 1.4 MPa, a 1.5 kW refrigerator, a centrifugal SHE pump with a flow rate of 300 g/s and peripherals. After system integration, performance tests have been carried out. In a preliminary cooling test without magnets, the cryogenic system attained a cooling capacity of 522 W by circulating supercritical helium flow of 300 g/s at 0.4 MPa and at 4.5 K. Afterwards a full system test with the magnets was carried out. The magnets were successfully charged up to an ultimate current of 5000 A beyond a nominal current of 4400 A. This paper describes the plant design and the result of performance measurements.

Advanced Space Suit PLSS 2.0 Cooling Loop Evaluation and PLSS 2.5 Recommendations

NASA Technical Reports Server (NTRS)

Steele, John; Quinn, Greg; Campbell, Colin; Makinen, Janice; Watts, Carly; Westheimer, David

2016-01-01

From 2012 to 2015 The NASA/JSC AdvSS (Advanced Space Suit) PLSS (Portable Life Support Subsystem) team, with support from UTC Aerospace Systems, performed the build-up, packaging and testing of PLSS 2.0. One aspect of that testing was the evaluation of the long-term health of the water cooling circuit and the interfacing components. Periodic and end-of-test water, residue and hardware analyses provided valuable information on the status of the water cooling circuit, and the approaches that would be necessary to enhance water cooling circuit health in the future. The evaluated data has been consolidated, interpreted and woven into an action plan for the maintenance of water cooling circuit health for the planned FY (fiscal year) 2016 through FY 2018 PLSS 2.5 testing. This paper provides an overview of the PLSS 2.0 water cooling circuit findings and the associated steps to be taken in that regard for the PLSS 2.5.

Model validation using CFD-grade experimental database for NGNP Reactor Cavity Cooling Systems with water and air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manera, Annalisa; Corradini, Michael; Petrov, Victor

This project has been focused on the experimental and numerical investigations of the water-cooled and air-cooled Reactor Cavity Cooling System (RCCS) designs. At this aim, we have leveraged an existing experimental facility at the University of Wisconsin-Madison (UW), and we have designed and built a separate effect test facility at the University of Michigan. The experimental facility at UW has underwent several upgrades, including the installation of advanced instrumentation (i.e. wire-mesh sensors) built at the University of Michigan. These provides highresolution time-resolved measurements of the void-fraction distribution in the risers of the water-cooled RCCS facility. A phenomenological model has beenmore » developed to assess the water cooled RCCS system stability and determine the root cause behind the oscillatory behavior that occurs under normal two-phase operation. Testing under various perturbations to the water-cooled RCCS facility have resulted in changes in the stability of the integral system. In particular, the effects on stability of inlet orifices, water tank volume have and system pressure been investigated. MELCOR was used as a predictive tool when performing inlet orificing tests and was able to capture the Density Wave Oscillations (DWOs) that occurred upon reaching saturation in the risers. The experimental and numerical results have then been used to provide RCCS design recommendations. The experimental facility built at the University of Michigan was aimed at the investigation of mixing in the upper plenum of the air-cooled RCCS design. The facility has been equipped with state-of-theart high-resolution instrumentation to achieve so-called CFD grade experiments, that can be used for the validation of Computational Fluid Dynanmics (CFD) models, both RANS (Reynold-Averaged) and LES (Large Eddy Simulations). The effect of risers penetration in the upper plenum has been investigated as well.« less

Acoustic and Thermal Testing of an Integrated Multilayer Insulation and Broad Area Cooling Shield System

NASA Technical Reports Server (NTRS)

Wood, Jessica J.; Foster, Lee W.

2013-01-01

A Multilayer Insulation (MLI) and Broad Area Cooling (BAC) shield thermal control system shows promise for long-duration storage of cryogenic propellant. The NASA Cryogenic Propellant Storage and Transfer (CPST) project is investigating the thermal and structural performance of this tank-applied integrated system. The MLI/BAC Shield Acoustic and Thermal Test was performed to evaluate the MLI/BAC shield's structural performance by subjecting it to worst-case launch acoustic loads. Identical thermal tests using Liquid Nitrogen (LN2) were performed before and after the acoustic test. The data from these tests was compared to determine if any degradation occurred in the thermal performance of the system as a result of exposure to the acoustic loads. The thermal test series consisted of two primary components: a passive boil-off test to evaluate the MLI performance and an active cooling test to evaluate the integrated MLI/BAC shield system with chilled vapor circulating through the BAC shield tubes. The acoustic test used loads closely matching the worst-case envelope of all launch vehicles currently under consideration for CPST. Acoustic test results yielded reasonable responses for the given load. The thermal test matrix was completed prior to the acoustic test and successfully repeated after the acoustic test. Data was compared and yielded near identical results, indicating that the MLI/BAC shield configuration tested in this series is an option for structurally implementing this thermal control system concept.

Coolant effectiveness in dental cutting with air-turbine handpieces.

PubMed

Leung, Brian T W; Dyson, John E; Darvell, Brian W

2012-03-01

To establish a strategy for evaluating coolant effectiveness and to compare typical cooling conditions used in dental cutting. A test system comprising a resistive heat source and an array of four type K thermocouples was used to compare the cooling effectiveness of air alone, water stream alone, and an air-water spray, as delivered by representative air-turbine handpieces. Mean temperature change at the four sites was recorded for a range of water flow rates in the range 10 to 90 mL min(-1), with and without air, and with and without the turbine running. The thermal resistance of the system, R, was calculated as the temperature change per watt (KW(-1)). For wet cooling (water stream and air-water spray), R was 5.1 to 11.5 KW(-1), whereas for air coolant alone the range was 18.5 to 30.7 KW(-1). R for air-water spray was lower than for water stream cooling at the same flow rate. The thermal resistivity approach is a viable means of comparative testing of cooling efficacy in simulated dental cutting. It may provide a reliable means of testing handpiece nozzle design, thus enabling the development of more efficient cooling.

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2010 CFR

2010-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

Film Cooled Recession of SiC/SiC Ceramic Matrix Composites: Test Development, CFD Modeling and Experimental Observations

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Sakowski, Barbara A.; Fisher, Caleb

2014-01-01

SiCSiC ceramic matrix composites (CMCs) systems will play a crucial role in next generation turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures, reduce engine weight and cooling requirements. However, the environmental stability of Si-based ceramics in high pressure, high velocity turbine engine combustion environment is of major concern. The water vapor containing combustion gas leads to accelerated oxidation and corrosion of the SiC based ceramics due to the water vapor reactions with silica (SiO2) scales forming non-protective volatile hydroxide species, resulting in recession of the ceramic components. Although environmental barrier coatings are being developed to help protect the CMC components, there is a need to better understand the fundamental recession behavior of in more realistic cooled engine component environments.In this paper, we describe a comprehensive film cooled high pressure burner rig based testing approach, by using standardized film cooled SiCSiC disc test specimen configurations. The SiCSiC specimens were designed for implementing the burner rig testing in turbine engine relevant combustion environments, obtaining generic film cooled recession rate data under the combustion water vapor conditions, and helping developing the Computational Fluid Dynamics (CFD) film cooled models and performing model validation. Factors affecting the film cooled recession such as temperature, water vapor concentration, combustion gas velocity, and pressure are particularly investigated and modeled, and compared with impingement cooling only recession data in similar combustion flow environments. The experimental and modeling work will help predict the SiCSiC CMC recession behavior, and developing durable CMC systems in complex turbine engine operating conditions.

Measured performance of a 3 ton LiBr absorption water chiller and its effect on cooling system operation

NASA Technical Reports Server (NTRS)

Namkoong, D.

1976-01-01

A three ton lithium bromide absorption water chiller was tested for a number of conditions involving hot water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It was concluded that a three-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

Measured performance of a 3-ton LiBr absorption water chiller and its effect on cooling system operation

NASA Technical Reports Server (NTRS)

Namkoong, D.

1976-01-01

A 3-ton lithium bromide absorption water chiller was tested for a number of conditions involving hot-water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It is concluded that a 3-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

77 FR 60481 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-03

...The U.S. Nuclear Regulatory Commission (NRC or the Commission) is issuing a revision to Regulatory Guide (RG) 1.52, ``Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-accident Engineered-Safety-Feature Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants.'' This guide applies to the design, inspection, and testing of air filtration and iodine adsorption units of engineered-safety-feature (ESF) atmosphere cleanup systems in light-water-cooled nuclear power plants.

Thermal Propulsion Capture System Heat Exchanger Design

NASA Technical Reports Server (NTRS)

Richard, Evan M.

2016-01-01

One of the biggest challenges of manned spaceflight beyond low earth orbit and the moon is harmful radiation that astronauts would be exposed to on their long journey to Mars and further destinations. Using nuclear energy has the potential to be a more effective means of propulsion compared to traditional chemical engines (higher specific impulse). An upper stage nuclear engine would allow astronauts to reach their destination faster and more fuel efficiently. Testing these engines poses engineering challenges due to the need to totally capture the engine exhaust. The Thermal Propulsion Capture System is a concept for cost effectively and safely testing Nuclear Thermal Engines. Nominally, hydrogen exhausted from the engine is not radioactive, but is treated as such in case of fuel element failure. The Thermal Propulsion Capture System involves injecting liquid oxygen to convert the hydrogen exhaust into steam. The steam is then cooled and condensed into liquid water to allow for storage. The Thermal Propulsion Capture System concept for ground testing of a nuclear powered engine involves capturing the engine exhaust to be cooled and condensed before being stored. The hydrogen exhaust is injected with liquid oxygen and burned to form steam. That steam must be cooled to saturation temperatures before being condensed into liquid water. A crossflow heat exchanger using water as a working fluid will be designed to accomplish this goal. Design a cross flow heat exchanger for the Thermal Propulsion Capture System testing which: Eliminates the need for water injection cooling, Cools steam from 5800 F to saturation temperature, and Is efficient and minimizes water requirement.

Cool pool development. Quarterly technical report No. 2, June-December 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crowther, K.

1980-01-05

The Cool Pool is a variation of the evaporating roof pond idea. The pool is isolated from the living space and the cooled pond water thermosiphons into the water columns located within the building. A computer model of the Cool Pool and the various heat and mass transfer mechanisms involved in the system are discussed. Theory will be compared to experimental data collected from a Cool Pool test building.

Preliminary study of TEC application in cooling system

NASA Astrophysics Data System (ADS)

Sulaiman, A. C.; Amin, N. A. M.; Saidon, M. S.; Majid, M. S. A.; Rahman, M. T. A.; Kazim, M. N. F. M.

2017-10-01

Integration of thermoelectric cooling (TEC) within a space cooling system in the lecturer room is studied. The studied area (air conditioned surrounding) is encapsulated with wall, floor, roof, and glass window. TEC module is placed on the glass window. The prototype of the studied compartment is designed using cabin container. The type and number of TEC module are studied and the effects on the cooling performance are analyzed as it is assumed to be tested within an air conditioned lecturer room. The experimental and mathematical modeling of the cooling system developed. It is expected that the mathematical modeling derived from this study will be used to estimate the use of the number of TEC module to be integrated with air conditioner unit where possible.

Oxygen-hydrogen thrusters for Space Station auxiliary propulsion systems

NASA Technical Reports Server (NTRS)

Berkman, D. K.

1984-01-01

The feasibility and technology requirements of a low-thrust, high-performance, long-life, gaseous oxygen (GO2)/gaseous hydrogen (GH2) thruster were examined. Candidate engine concepts for auxiliary propulsion systems for space station applications were identified. The low-thrust engine (5 to 100 lb sub f) requires significant departure from current applications of oxygen/hydrogen propulsion technology. Selection of the thrust chamber material and cooling method needed or long life poses a major challenge. The use of a chamber material requiring a minimum amount of cooling or the incorporation of regenerative cooling were the only choices available with the potential of achieving very high performance. The design selection for the injector/igniter, the design and fabrication of a regeneratively cooled copper chamber, and the design of a high-temperature rhenium chamber were documented and the performance and heat transfer results obtained from the test program conducted at JPL using the above engine components presented. Approximately 115 engine firings were conducted in the JPL vacuum test facility, using 100:1 expansion ratio nozzles. Engine mixture ratio and fuel-film cooling percentages were parametrically investigated for each test configuration.

Advanced Design Heat PumpRadiator for EVA Suits

NASA Technical Reports Server (NTRS)

Izenson, Michael G.; Chen, Weibo; Passow, Christian; Phillips, Scott; Trevino, Luis

2009-01-01

Absorption cooling using a LiCl/water heat pump can enable lightweight and effective thermal control for EVA suits without venting water to the environment. The key components in the system are an absorber/radiator that rejects heat to space and a flexible evaporation cooling garment that absorbs heat from the crew member. This paper describes progress in the design, development, and testing of the absorber/radiator and evaporation cooling garment. New design concepts and fabrication approaches will significantly reduce the mass of the absorber/radiator. We have also identified materials and demonstrated fabrication approaches for production of a flexible evaporation cooling garment. Data from tests of the absorber/radiator s modular components have validated the design models and allowed predictions of the size and weight of a complete system.

Active cooling from the sixties to NASP

NASA Technical Reports Server (NTRS)

Kelly, H. Neale; Blosser, Max L.

1994-01-01

Vehicles, such as the X-15 or the National Aerospace Plane (NASP), traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of the present paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years, from early engine structures which were intended to be tested on the X-15 to structural panels fabricated and tested under the NASP program, are described. Many of the lessons learned from these research efforts are presented.

Analysis of economic and environmental benefits of a new heat pump air conditioning system with a heat recovery device

NASA Astrophysics Data System (ADS)

Li, lingxue

2017-08-01

The paper designs a new wind-water cooling and heating water conditioner system, connects cooling tower with heat recovery device, which uses cooling water to completely remove the heat that does not need heat recollection, in order to ensure that the system can work efficiently with higher performance coefficient. After the test actual engineering operation, the system’s maximum cooling coefficient of performance can reach 3.5. Its maximum comprehensive coefficient of performance can reach 6.5. After the analysis of its economic and environmental, we conclude that the new system can save 89822 kw per year. It reflects energy-saving and environmental benefits of the cold and hot water air conditioning system.

Preliminary Model Tests of a Wing-Duct Cooling System for Radial Engines, Special Report

NASA Technical Reports Server (NTRS)

Biermann, David; Valentine, E. Floyd

1939-01-01

Wind-tunnel tests were conducted on a model wing-nacelle combination to determine the practicability of cooling radial engines by forcing the cooling air into wing-duct entrances located in the propeller slipstream, passing the air through the engine baffles from rear to front, and ejecting the air through an annular slot near the front of the nacelle. The tests, which were of a preliminary nature, were made on a 5-foot-chord wing and a 20-inch-diameter nacelle. A 3-blade, 4-foot-diameter propeller was used. The tests indicated that this method of cooling and cowling radial engines is entirely practicable providing the wing of the prospective airplane is sufficiently thick to accommodate efficient entrance ducts , The drag of the cowlings tested was definitely less than for the conventional N.A.C.A. cowling, and the pressure available at low air speed corresponding to operation on the ground and at low flying speeds was apparently sufficient for cooling most present-day radial engines.

Establishment and assessment of code scaling capability

NASA Astrophysics Data System (ADS)

Lim, Jaehyok

In this thesis, a method for using RELAP5/MOD3.3 (Patch03) code models is described to establish and assess the code scaling capability and to corroborate the scaling methodology that has been used in the design of the Purdue University Multi-Dimensional Integral Test Assembly for ESBWR applications (PUMA-E) facility. It was sponsored by the United States Nuclear Regulatory Commission (USNRC) under the program "PUMA ESBWR Tests". PUMA-E facility was built for the USNRC to obtain data on the performance of the passive safety systems of the General Electric (GE) Nuclear Energy Economic Simplified Boiling Water Reactor (ESBWR). Similarities between the prototype plant and the scaled-down test facility were investigated for a Gravity-Driven Cooling System (GDCS) Drain Line Break (GDLB). This thesis presents the results of the GDLB test, i.e., the GDLB test with one Isolation Condenser System (ICS) unit disabled. The test is a hypothetical multi-failure small break loss of coolant (SB LOCA) accident scenario in the ESBWR. The test results indicated that the blow-down phase, Automatic Depressurization System (ADS) actuation, and GDCS injection processes occurred as expected. The GDCS as an emergency core cooling system provided adequate supply of water to keep the Reactor Pressure Vessel (RPV) coolant level well above the Top of Active Fuel (TAF) during the entire GDLB transient. The long-term cooling phase, which is governed by the Passive Containment Cooling System (PCCS) condensation, kept the reactor containment system that is composed of Drywell (DW) and Wetwell (WW) below the design pressure of 414 kPa (60 psia). In addition, the ICS continued participating in heat removal during the long-term cooling phase. A general Code Scaling, Applicability, and Uncertainty (CSAU) evaluation approach was discussed in detail relative to safety analyses of Light Water Reactor (LWR). The major components of the CSAU methodology that were highlighted particularly focused on the scaling issues of experiments and models and their applicability to the nuclear power plant transient and accidents. The major thermal-hydraulic phenomena to be analyzed were identified and the predictive models adopted in RELAP5/MOD3.3 (Patch03) code were briefly reviewed.

An experimental study of heat pipe thermal management system with wet cooling method for lithium ion batteries

NASA Astrophysics Data System (ADS)

Zhao, Rui; Gu, Junjie; Liu, Jie

2015-01-01

An effective battery thermal management (BTM) system is required for lithium-ion batteries to ensure a desirable operating temperature range with minimal temperature gradient, and thus to guarantee their high efficiency, long lifetime and great safety. In this paper, a heat pipe and wet cooling combined BTM system is developed to handle the thermal surge of lithium-ion batteries during high rate operations. The proposed BTM system relies on ultra-thin heat pipes which can efficiently transfer the heat from the battery sides to the cooling ends where the water evaporation process can rapidly dissipate the heat. Two sized battery packs, 3 Ah and 8 Ah, with different lengths of cooling ends are used and tested through a series high-intensity discharges in this study to examine the cooling effects of the combined BTM system, and its performance is compared with other four types of heat pipe involved BTM systems and natural convection cooling method. A combination of natural convection, fan cooling and wet cooling methods is also introduced to the heat pipe BTM system, which is able to control the temperature of battery pack in an appropriate temperature range with the minimum cost of energy and water spray.

Preliminary design package for prototype solar heating and cooling systems

NASA Technical Reports Server (NTRS)

1978-01-01

A summary is given of the preliminary analysis and design activity on solar heating and cooling systems. The analysis was made without site specific data other than weather; therefore, the results indicate performance expected under these special conditions. Major items include a market analysis, design approaches, trade studies and other special data required to evaluate the preliminary analysis and design. The program calls for the development and delivery of eight prototype solar heating and cooling systems for installation and operational test. Two heating and six heating and cooling units will be delivered for Single Family Residences, Multiple-family Residences and commercial applications.

Flowpath evaluation and reconnaissance by remote field Eddy current testing (FERRET)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smoak, A.E.; Zollinger, W.T.

1993-12-31

This document describes the design and development of FERRET (Flowpath Evaluation and Reconnaisance by Remote-field Eddy current Testing). FERRET is a system for inspecting the steel pipes which carry cooling water to underground nuclear waste storage tanks. The FERRET system has been tested in a small scale cooling pipe mock-up, an improved full scale mock-up, and in flaw detection experiments. Early prototype designs of FERRET and the FERRET launcher (a device which inserts, moves, and retrieves probes from a piping system) as well as the field-ready design are discussed.

Prototype solar heating and combined heating and cooling systems

NASA Technical Reports Server (NTRS)

1977-01-01

System analysis activities were directed toward refining the heating system parameters. Trade studies were performed to support hardware selections for all systems and for the heating only operational test sites in particular. The heating system qualification tests were supported by predicting qualification test component performance prior to conducting the test.

Preliminary Tests of Blowers of Three Designs Operating in Conjunction with a Wing-Duct Cooling System for Radial Engines, Special Report

NASA Technical Reports Server (NTRS)

Biermann, David; Valentine, E. Floyd

1939-01-01

This paper is one of several dealing with methods intended to reduce the drag of present-day radial engine installations and improve the cooling at zero and low air speeds, The present paper describes model wind-tunnel tests of blowers of three designs tested in conjunction with a wing-nacelle combination. The principle of operation involved consists of drawing cooling air into ducts located in the wing root at the point of maximum slipstream velocity, passing the air through the engine baffles from rear to front, and exhausting the air through an annular slot located between the propeller and the engine with the aid of a blower mounted on the spinner. The test apparatus consisted essentially of a stub wing having a 5-foot chord and a 15-foot span, an engine nacelle of 20 inches diameter enclosing a 25-horsepower electric motor, and three blowers mounted on propeller spinners. Two of the blowers utilize centrifugal force while the other uses the lift from airfoils to force the air out radially through the exit slot. Maximum efficiencies of over 70 percent were obtained for the system as a whole. Pressures were measured over the entire flight range which were in excess of those necessary to cool present-day engines, The results indicated that blowers mounted on propeller spinners could be built sufficiently powerful and efficient to warrant their use as the only, or chief, means of forcing air through the cooling system, so that cooling would be independent of the speed of the airplane.

Phase I, open-cycle absorption solar cooling. Part IV. Executive summary analysis and resolution of critical issues and recommendations for Phase II. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, B.D.

The objective of this project is to advance lower cost solar cooling technology with the feasibility analysis, design and evaluation of proof-of-concept open cycle solar cooling concepts. The work is divided into three phases, with planned completion of each phase before proceeding with the following phase: Phase I - performance/economic/environmental related analysis and exploratory studies; Phase II - design and construction of an experimental system, including evaluative testing; Phase III - extended system testing during operation and engineering modifications as required. For Phase I, analysis and resolution of critical issues were completed with the objective of developing design specifications formore » an improved prototype OCA system.« less

KSC-02pd0029

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility test the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. The worker at right is using a black light. NICMOS II is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

Operational Characteristics of Four Commercially Available Personal Cooling Vests

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Montgomery, Leslie D.; Lee, Hank C.; Webbon, Bruce W.; Kliss, Mark (Technical Monitor)

1997-01-01

Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to compare the effectiveness of two passive and two active cooling vests, and to measure the body temperature and circulatory changes produced by each cooling vest configuration. The MicroClimate Systems and the Life Enhancement Tech(LET) lightweight liquid cooling vests, the Steele Vest and LET's Zipper Front Garment were used to cool the chest region of 11 male and 10 female subjects (25 to 55 yr.) in this study. Calf, forearm and finger blood flows were measured using a tetrapolar impedance rheograph. The subjects, seated in an upright position at normal room temperature (approx.21 C), were tested for 60 min. with the cooling system operated at its maximum cooling capacity. Blood flows were recorded continuously using a computer data acquisition system with a sampling frequency of 250 Hz. Oral, right and left ear temperatures and cooling system parameters were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; respiration; and an activity index were recorded continuously on a URI Inc. Biolog ambulatory monitor. In general, the male and female subjects' rectal and ear temperature responses to cooling were similar for all vest configurations tested. Oral temperatures during the recovery period were significantly (P<0.05) lower than during the control period, approx.0.2 - 0.5 C, for both men and women wearing any of the four different garments. The corresponding car temperatures were significantly (P<0.05) decreased approx.0.2 - 0.3 C by the end of the recovery period. Compared to the control period, no significant differences were found in rectal temperatures during cooling and recovery periods. These results show that all vest configurations elicit a similar thermal response in both male and female subject groups. However, subject population variance was rather large and may have masked differences between the vests. One vest may prove more effective than another for a given individual, and experience is the only means of determining this.

Advances in measuring techniques for turbine cooling test rigs - Status report

NASA Technical Reports Server (NTRS)

Pollack, F. G.

1974-01-01

Instrumentation development pertaining to turbine cooling research has resulted in the design and testing of several new systems. Pressure measurements on rotating components are being made with a rotating system incorporating ten miniature transducers and a slip-ring assembly. The system has been tested successfully up to speeds of 9000 rpm. An advanced system development combining pressure transducer and thermocouple signals is also underway. Thermocouple measurements on rotating components are transferred off the shaft by a 72-channel rotating data system. Thermocouple data channels are electronically processed on board and then removed from the shaft in the form of a digital serial train by one winding of a rotary transformer.

Implementing a frame representation in CLIPS/COOL

NASA Technical Reports Server (NTRS)

Myers, Leonard; Snyder, James

1991-01-01

An implementation is described and evaluated of frames in COOL. The test case is a frame based semantic network previously implemented in CLIPS (C Language Integrated Production System) Version 4.3 as part of the Intelligent Computer Aided Design System (ICADS) and reported at the first CLIPS conference.

Mini-Membrane Evaporator for Contingency Spacesuit Cooling

NASA Technical Reports Server (NTRS)

Makinen, Janice V.; Bue, Grant C.; Campbell, Colin; Petty, Brian; Craft, Jesse; Lynch, William; Wilkes, Robert; Vogel, Matthew

2015-01-01

The next-generation Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System (PLSS) is integrating a number of new technologies to improve reliability and functionality. One of these improvements is the development of the Auxiliary Cooling Loop (ACL) for contingency crewmember cooling. The ACL is a completely redundant, independent cooling system that consists of a small evaporative cooler--the Mini Membrane Evaporator (Mini-ME), independent pump, independent feedwater assembly and independent Liquid Cooling Garment (LCG). The Mini-ME utilizes the same hollow fiber technology featured in the full-sized AEMU PLSS cooling device, the Spacesuit Water Membrane Evaporator (SWME), but Mini-ME occupies only approximately 25% of the volume of SWME, thereby providing only the necessary crewmember cooling in a contingency situation. The ACL provides a number of benefits when compared with the current EMU PLSS contingency cooling technology, which relies upon a Secondary Oxygen Vessel; contingency crewmember cooling can be provided for a longer period of time, more contingency situations can be accounted for, no reliance on a Secondary Oxygen Vessel (SOV) for contingency cooling--thereby allowing a reduction in SOV size and pressure, and the ACL can be recharged-allowing the AEMU PLSS to be reused, even after a contingency event. The first iteration of Mini-ME was developed and tested in-house. Mini-ME is currently packaged in AEMU PLSS 2.0, where it is being tested in environments and situations that are representative of potential future Extravehicular Activities (EVA's). The second iteration of Mini-ME, known as Mini-ME2, is currently being developed to offer more heat rejection capability. The development of this contingency evaporative cooling system will contribute to a more robust and comprehensive AEMU PLSS.

Mini-Membrane Evaporator for Contingency Spacesuit Cooling

NASA Technical Reports Server (NTRS)

Makinen, Janice V.; Bue, Grant C.; Campbell, Colin; Craft, Jesse; Lynch, William; Wilkes, Robert; Vogel, Matthew

2014-01-01

The next-generation Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System (PLSS) is integrating a number of new technologies to improve reliability and functionality. One of these improvements is the development of the Auxiliary Cooling Loop (ACL) for contingency crewmember cooling. The ACL is a completely redundant, independent cooling system that consists of a small evaporative cooler--the Mini Membrane Evaporator (Mini-ME), independent pump, independent feedwater assembly and independent Liquid Cooling Garment (LCG). The Mini-ME utilizes the same hollow fiber technology featured in the full-sized AEMU PLSS cooling device, the Spacesuit Water Membrane Evaporator (SWME), but Mini-ME occupies only 25% of the volume of SWME, thereby providing only the necessary crewmember cooling in a contingency situation. The ACL provides a number of benefits when compared with the current EMU PLSS contingency cooling technology, which relies upon a Secondary Oxygen Vessel; contingency crewmember cooling can be provided for a longer period of time, more contingency situations can be accounted for, no reliance on a Secondary Oxygen Vessel (SOV) for contingency cooling--thereby allowing a reduction in SOV size and pressure, and the ACL can be recharged-allowing the AEMU PLSS to be reused, even after a contingency event. The first iteration of Mini-ME was developed and tested in-house. Mini-ME is currently packaged in AEMU PLSS 2.0, where it is being tested in environments and situations that are representative of potential future Extravehicular Activities (EVA's). The second iteration of Mini-ME, known as Mini- ME2, is currently being developed to offer more heat rejection capability. The development of this contingency evaporative cooling system will contribute to a more robust and comprehensive AEMU PLSS.

Solar-energy-system performance evaluation: Honeywell OTS 44, Ocmulgee, Georgia

NASA Technical Reports Server (NTRS)

Mathur, A. K.; Pederson, S.

1982-01-01

The operation and technical performance of the solar operational test site (OTS 44) are described, based on data collected between April, 1981 and August, 1981. The following topics are discussed: system description, performance assessment, operating energy, energy savings, system maintenance, and conclusions. The solar energy system at OTS 44 is a hydronic heating and cooling system consisting of 5040 square feet of liquid cooled flat plate collectors; a 4000 gallon thermal storage tank; one 25 ton capacity organic Rankine cycle engine assisted water chillers; a forced draft cooling tower; and associated piping, pumps, valves, controls and heat rejection equipment. The solar system has eight basic modes of operation and several combination modes for providing space conditioning and hot water to the building. Data monitored during the 4 months of the operational test period found that the solar system collected 285 MMBtu of thermal energy of the total incident solar energy of 1040 MMBtu and provided 210 MMBtu for cooling and 10 MMBtu for heating and hot water. The net electrical energy saving due to the solar system was approximately 2600 kWh(e), and fossil energy saving was about 20 million Btu (MMBtu).

Crosswinds Effect on the Thermal Performance of Wet Cooling Towers Under Variable Operating Conditions

NASA Astrophysics Data System (ADS)

Chen, You Liang; Shi, Yong Feng; Hao, Jian Gang; Chang, Hao; Sun, Feng Zhong

2018-01-01

In order to quantitatively analyze the influence of the variable operating parameters on the cooling performance of natural draft wet cooling towers (NDWCTs), a hot model test system was set up with adjustable ambient temperature and humidity, circulating water flowrate and temperature. In order to apply the hot model test results to the real tower, the crosswind Froude number is defined. The results show that the crosswind has a negative effect on the thermal performance of the cooling tower, and there is a critical crosswind velocity corresponding to the lowest cooling efficiency. According to the crosswind Froude number similarity, when the ambient temperature decreases, or the circulating water flowrate and temperature increase, the cooling tower draft force will increase, and the critical crosswind velocity will increase correspondingly.

Engineering evaluation of magma cooling-tower demonstration at Nevada Power Company's Sunrise Station

NASA Astrophysics Data System (ADS)

1980-11-01

The Magma Cooling Tower (MCT) process utilizes a falling film heat exchanger integrated into an induced draft cooling tower to evaporate waste water. A hot water source such as return cooling water provides the energy for evaporation. Water quality control is maintained by removing potential scaling constituents to make concentrations of the waste water possible without scaling heat transfer surfaces. A pilot-scale demonstration test of the MCT process was performed from March 1979 through June 1979 at Nevada Power Company's Sunrise Station in Las Vegas, Nevada. The pilot unit extracted heat from the powerplant cooling system to evaporate cooling tower blowdown. Two water quality control methods were employed: makeup/sidestream softening and fluidized bed crystallization. The 11 week softening mode test was successful.

Solar energy system installed at the North Georgia APDC office building

NASA Technical Reports Server (NTRS)

1979-01-01

A hydronic, automatic drain-down solar heating and cooling system is described. The system provides solar heat exchange from a 2,001 square foot effective collector area and supplies 65-70 percent of the building's cooling demand, 90-95 percent of the heating demand, and domestic hot water. The acceptance test plan and results, system operation and maintenance, and predicted system performance are presented.

The x-ray telescope eROSITA: qualification of the thermal control system

NASA Astrophysics Data System (ADS)

Fürmetz, Maria; Eder, Josef; Pfeffermann, Elmar; Predehl, Peter

2014-07-01

eROSITA is the core instrument on the Spektrum-Röntgen-Gamma (SRG) mission, scheduled for launch in 2016. The main tasks of the thermal control system are heating of the mirror modules, cooling of the camera electronics, cooling of the CCD detectors and temperature control of the telescope structure in general. Special attention is paid to the camera cooling, since it is the most critical one. The complex assembly with the sevenfold symmetry of the eROSITA telescope requires an innovative design. Large distances and a very low operating temperature (-90°C to -100°C) place high demands on the cooling chain. In total, three different types of low-temperature ethane heat pipes are used to transport the heat from the cameras to two radiators outside the telescope structure. Extreme environmental temperature gradients with the Sun on the one side and the cold space on the other present a real challenge not only to the camera cooling systems, but to the overall thermal control. A thermal model of the complete telescope was used to predict the thermal behavior of the telescope and its subsystems. Through various tests, this model could be improved step by step. The most complex test was the space simulation test of the eROSITA qualification model in January 2013 at the IABG facilities in Ottobrunn, Germany. About 50 heaters, a liquid-nitrogen-cooled chamber and a Sun simulator provided realistic mission conditions. Approximately 200 temperature sensors monitored the relevant temperatures during the test. The results were predominantly within the predicted intervals and therefore not only verified the complete concept but also enabled a further refining of the thermal model. This, in turn, allows for reliable predictions of the thermal behavior during the mission. Some deviations required minor changes in the final design which were implemented and re-qualified in a separate test of the thermal control system flight model in March 2014 in the PANTER test facility of MPE. The results of both tests will be presented in this contribution.

Flight Test Results for the HST Orbital Systems Test (HOST) Capillary Pump Loop Cooling System

NASA Technical Reports Server (NTRS)

Buchko, M.; Kaylor, M.; Kroliczek, E.; Ottenstein, L.

1999-01-01

The Near Infrared Camera and Multi Object Spectrometer (NICMOS) was installed in the Hubble Space Telescope (MST) in February 1997. Shortly thereafter, the instrument experienced a thermal short in its solid nitrogen dewar system which will significantly shorten the instrument's useful life. A reverse Brayton cycle mechanical refrigerator will be installed during the Third Servicing Mission (SM3) to provide cooling for the instrument, and thereby extend its operations. A Capillary Pump Loop (CPL) and radiator system was designed, built and tested to remove up to 500 watts of heat from the mechanical cryocooler and its associated electronics. The HST Orbital Systems Test (HOST) platform was flown on the Space Shuttle Discovery (STS-95) as a flight demonstration of the cryocooler system, CPL control electronics, and the CPL/Radiator. This paper will present the flight test results and thermal performance of the CPL system in detail.

Development of a Pressure Box to Evaluate Reusable-Launch-Vehicle Cryogenic-Tank Panels

NASA Technical Reports Server (NTRS)

Ambur, Damodar R.; Sikora, Joseph; Maguire, James F.; Winn, Peter M.

1996-01-01

A cryogenic pressure-box test machine has been designed and is being developed to test full-scale reusable-launch-vehicle cryogenic-tank panels. This machine is equipped with an internal pressurization system, a cryogenic cooling system, and a heating system to simulate the mechanical and thermal loading conditions that are representative of a reusable-launch-vehicle mission profile. The cryogenic cooling system uses liquid helium and liquid nitrogen to simulate liquid hydrogen and liquid oxygen tank internal temperatures. A quartz lamp heating system is used for heating the external surface of the test panels to simulate cryogenic-tank external surface temperatures during re-entry of the launch vehicle. The pressurization system uses gaseous helium and is designed to be controlled independently of the cooling system. The tensile loads in the axial direction of the test panel are simulated by means of hydraulic actuators and a load control system. The hoop loads in the test panel are reacted by load-calibrated turnbuckles attached to the skin and frame elements of the test panel. The load distribution in the skin and frames can be adjusted to correspond to the tank structure by using these turnbuckles. The seal between the test panel and the cryogenic pressure box is made from a reinforced Teflon material which can withstand pressures greater than 52 psig at cryogenic temperatures. Analytical results and tests on prototype test components indicate that most of the cryogenic-tank loading conditions that occur in flight can be simulated in the cryogenic pressure-box test machine.

Zero Boil-Off System Testing

NASA Technical Reports Server (NTRS)

Plachta, David W.; Johnson, Wesley L.; Feller, Jeffrey R.

2015-01-01

Cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) are a part of NASA's future space exploration due to their high specific impulse for rocket motors of upper stages suitable for transporting 10s to 100s of metric tons of payload mass to destinations outside of low earth orbit and for their return. However, the low storage temperatures of LH2 and LO2 cause substantial boil-off losses for missions with durations greater than several months. These losses can be eliminated by incorporating high performance cryocooler technology to intercept heat load to the propellant tanks and modulating the cryocooler to control tank pressure. The active thermal control technology being developed by NASA is the reverse turbo-Brayton cycle cryocooler and its integration to the propellant tank through a distributed cooling tubing network coupled to the tank wall. This configuration was recently tested at NASA Glenn Research Center, in a vacuum chamber and cryoshroud that simulated the essential thermal aspects of low Earth orbit, its vacuum and temperature. Testing consisted of three passive tests with the active cryocooler system off, and 7 active tests, with the cryocooler powered up. The test matrix included zero boil-off tests performed at 90 full and 25 full, and several demonstrations at excess cooling capacity and reduced cooling capacity. From this, the tank pressure response with varied cryocooler power inputs was determined. This test series established that the active cooling system integrated with the propellant tank eliminated boil-off and robustly controlled tank pressure.

Online Oxide Contamination Measurement and Purification Demonstration

NASA Technical Reports Server (NTRS)

Bradley, D. E.; Godfroy, T. J.; Webster, K. L.; Garber, A. E.; Polzin, K. A.; Childers, D. J.

2011-01-01

Liquid metal sodium-potassium (NaK) has advantageous thermodynamic properties indicating its use as a fission reactor coolant for a surface (lunar, martian) power system. A major area of concern for fission reactor cooling systems is system corrosion due to oxygen contaminants at the high operating temperatures experienced. A small-scale, approximately 4-L capacity, simulated fission reactor cooling system employing NaK as a coolant was fabricated and tested with the goal of demonstrating a noninvasive oxygen detection and purification system. In order to generate prototypical conditions in the simulated cooling system, several system components were designed, fabricated, and tested. These major components were a fully-sealed, magnetically-coupled mechanical NaK pump, a graphite element heated reservoir, a plugging indicator system, and a cold trap. All system components were successfully demonstrated at a maximum system flow rate of approximately 150 cc/s at temperatures up to 550 C. Coolant purification was accomplished using a cold trap before and after plugging operations which showed a relative reduction in oxygen content.

Biofouling reduction in recirculating cooling systems through biofiltration of process water.

PubMed

Meesters, K P H; Van Groenestijn, J W; Gerritse, J

2003-02-01

Biofouling is a serious problem in industrial recirculating cooling systems. It damages equipment, through biocorrosion, and causes clogging and increased energy consumption, through decreased heat transfer. In this research a fixed-bed biofilter was developed which removed assimilable organic carbon (AOC) from process water, thus limiting the major substrate for the growth of biofouling. The biofilter was tested in a laboratory model recirculating cooling water system, including a heat exchanger and a cooling tower. A second identical model system without a biofilter served as a reference. Both installations were challenged with organic carbon (sucrose and yeast extract) to provoke biofouling. The biofilter improved the quality of the recirculating cooling water by reducing the AOC content, the ATP concentration, bacterial numbers (30-40 fold) and the turbidity (OD660). The process of biofouling in the heat exchangers, the process water pipelines and the cooling towers, was monitored by protein increase, heat transfer resistance, and chlorine demanded for maintenance. This revealed that biofouling was lower in the system with the biofilter compared to the reference installation. It was concluded that AOC removal through biofiltration provides an attractive, environmental-friendly means to reduce biofouling in industrial cooling systems.

Laminated turbine vane design and fabrication. [utilizing film cooling as a cooling system

NASA Technical Reports Server (NTRS)

Hess, W. G.

1979-01-01

A turbine vane and associated endwalls designed for advanced gas turbine engine conditions are described. The vane design combines the methods of convection cooling and selective areas of full coverage film cooling. The film cooling technique is utilized on the leading edge, pressure side, and endwall regions. The turbine vane involves the fabrication of airfoils from a stack of laminates with cooling passages photoetched on the surface. Cold flow calibration tests, a thermal analysis, and a stress analysis were performed on the turbine vanes.

Advanced Heat Exchangers for Dry Cooling Systems, Phase II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fortini, Arthur J.; Horwath, Joseph

Dry cooling systems are an option for industrial and utility power plants that cannot obtain permits for cooling water or where cooling water is unavailable. Currently available dry cooling systems are more expensive and less efficient than wet cooling systems, so significant improvements in efficiency are needed to make them economically viable. Previous attempts at using foams as cooling fin materials for power generating systems have focused on high thermal conductivity graphite foams made via the Oak Ridge process. Because these materials have high flow restrictions and hence low permeability with respect to air flow, their internal volume and surfacemore » area were not effectively used. Consequently, they performed poorly and offered no advantage over aluminum fins. A foam with a more open structure would provide increased permeability, enable greater airflow through the bulk material, increase the rate of heat transfer, and enable the material to outperform traditional fin structures. In this project, Ultramet designed, fabricated, and tested low flow restriction, high-efficiency foam-based heat exchangers. Calculations based on existing thermal and hydraulic data for Ultramet’s high-performance open-cell foams indicated that 65-ppi (pores per linear inch) pyrolytic graphite foam with a relative density of 15 vol%, produced by chemical vapor infiltration (CVI), would have an effectiveness significantly greater than that of a state-of-the-art Hamon/Balcke-Durr aluminum fin system and greater than that of the POCO graphite foams previously tested for the DOE National Energy Technology Laboratory. Using the same chevron design, test setup, and run conditions as were used with the Hamon/Balcke-Durr fin system and the POCO foams, Ultramet tested graphite foams with air flow velocities of 0.07–3.2 m/sec and pressure drops of 0.03–9.7 inH2O. The best-performing graphite foam architectures had air velocities in excess of 2.5 m/sec when the pressure drop was 1 inH2O. Because a foam-based system is more efficient than a fin-based system, a smaller heat exchanger installation can be used, significantly reducing the installation cost. Furthermore, because the foam-based system is physically smaller with no increase in flow restriction, less electrical power is needed to run the fans to drive the air through the condenser. The result is a decrease in both the installation and operating costs, which in turn will decrease the overall life cycle cost of the system.« less

Solar Heating and Cooling for a Controls Manufacturing Plant Lumberton, New Jersey

NASA Technical Reports Server (NTRS)

1982-01-01

Comprehensive report documents computer-controlled system which has separate solar-collector and cooling-tower areas located away from building and is completely computer controlled. System description, test data, major problems and resolution, performance, operation and maintenance, manufacturer's literature and drawing comprise part of 257-page report.

Non-Venting Thermal and Humidity Control for EVA Suits

NASA Technical Reports Server (NTRS)

Izenson, Mike; Chen, Weibo; Bue, Grant

2011-01-01

Future EVA suits need processes and systems to control internal temperature and humidity without venting water to the environment. This paper describes an absorption-based cooling and dehumidification system as well as laboratory demonstrations of the key processes. There are two main components in the system: an evaporation cooling and dehumidification garment (ECDG) that removes both sensible heat and latent heat from the pressure garment, and an absorber radiator that absorbs moisture and rejects heat to space by thermal radiation. This paper discusses the overall design of both components, and presents recent data demonstrating their operation. We developed a design and fabrication approach to produce prototypical heat/water absorbing elements for the ECDG, and demonstrated by test that these elements could absorb heat and moisture at a high flux. Proof-of-concept tests showed that an ECDG prototype absorbs heat and moisture at a rate of 85 W/ft under conditions that simulate operation in an EVA suit. The heat absorption was primarily due to direct absorption of water vapor. It is possible to construct large, flexible, durable cooling patches that can be incorporated into a cooling garment with this system. The proof-of-concept test data was scaled to calculate area needed for full metabolic loads, thus showing that it is feasible to use this technology in an EVA suit. Full-scale, lightweight absorber/radiator modules have also been built and tested. They can reject heat at a flux of 33 W/ft while maintaining ECDG operation at conditions that will provide a cool and dry environment inside the EVA suit.

Heat Transfer Prediction of Film Cooling in Supersonic Flow

NASA Astrophysics Data System (ADS)

Luchi, Riccardo; Salvadori, Simone; Martelli, Francesco

2008-09-01

Considering the modern high pressure stages of gas turbines, the flow over the suction side of the blades can be affected by the presence of shock impingement and boundary layer separation. Furthermore, it should be pointed out that the combustor exit temperature reaches values which are close to the allowable material limit. Then, a cooling system based on the film cooling approach should be designed to prevent failure. The interaction between the ejected coolant and the shock impingement must be studied to achieve a higher efficiency of the cooling system. The proposed approach is based on the numerical evaluation of a film cooled test section experimentally studied at the University of Karlsruhe. The testing rig consists in a converging-diverging nozzle that accelerates the flow up to sonic conditions while an oblique shock is generated at the nozzle exit section. Three cases have been studied, changing the cooling holes position with respect to the shock impingement over the cooled surface. The obtained results are presented and compared with the experimental data. The used solver is the in-house CFD 3D code HybFlow, developed at the University of Florence. This study has been carried out in the frame of the EU funded TATEF2 project.

Spacesuit Water Membrane Evaporator; An Enhanced Evaporative Cooling System for the Advanced Extravehicular Mobility Unit Portable Life Support System

NASA Technical Reports Server (NTRS)

Bue, Grant C.; Makinen, Janice V.; Miller, Sean; Campbell, Colin; Lynch, Bill; Vogel, Matt; Craft, Jesse; Wilkes, Robert; Kuehnel, Eric

2014-01-01

Development of the Advanced Extravehicular Mobility Unit (AEMU) portable life support subsystem (PLSS) is currently under way at NASA Johnson Space Center. The AEMU PLSS features a new evaporative cooling system, the Generation 4 Spacesuit Water Membrane Evaporator (Gen4 SWME). The SWME offers several advantages when compared with prior crewmember cooling technologies, including the ability to reject heat at increased atmospheric pressures, reduced loop infrastructure, and higher tolerance to fouling. Like its predecessors, Gen4 SWME provides nominal crew member and electronics cooling by flowing water through porous hollow fibers. Water vapor escapes through the hollow fiber pores, thereby cooling the liquid water that remains inside of the fibers. This cooled water is then recirculated to remove heat from the crew member and PLSS electronics. Test results from the backup cooling system which is based on a similar design and the subject of a companion paper, suggested that further volume reductions could be achieved through fiber density optimization. Testing was performed with four fiber bundle configurations ranging from 35,850 fibers to 41,180 fibers. The optimal configuration reduced the Gen4 SWME envelope volume by 15% from that of Gen3 while dramatically increasing the performance margin of the system. A rectangular block design was chosen over the Gen3 cylindrical design, for packaging configurations within the AEMU PLSS envelope. Several important innovations were made in the redesign of the backpressure valve which is used to control evaporation. A twin-port pivot concept was selected from among three low profile valve designs for superior robustness, control and packaging. The backpressure valve motor, the thermal control valve, delta pressure sensors and temperature sensors were incorporated into the manifold endcaps, also for packaging considerations. Flight-like materials including a titanium housing were used for all components. Performance testing of the Gen4 SWME is underway.

Solar heating and cooling system installed at RKL Controls Company, Lumberton, New Jersey

NASA Technical Reports Server (NTRS)

1981-01-01

The final results of the design and operation of a computer controlled solar heated and cooled 40,000 square foot manufacturing building, sales office, and computer control center/display room are summarized. The system description, test data, major problems and resolutions, performance, operation and maintenance manual, equipment manufacturers' literature, and as-built drawings are presented. The solar system is composed of 6,000 square feet of flat plate collectors, external above ground storage subsystem, controls, absorption chiller, heat recovery, and a cooling tower.

External cooling efficiently controls intraosseous temperature rise caused by drilling in a drilling guide system: an in vitro study.

PubMed

Boa, Kristof; Varga, Endre; Pinter, Gabor; Csonka, Akos; Gargyan, Istvan; Varga, Endre

2015-12-01

The purpose of this study was to measure the rise in intraosseous temperature caused by drilling through a drilling guide system. We compared the rise in temperature generated, and the number of increases of more than 10 °C, between drills that had been cooled with saline at room temperature (25 °C) and those that had not been cooled, for every step of the drilling sequence. Cortical layers of bovine ribs were used as specimens, and they were drilled through 3-dimensional printed surgical guides. Heat was measured with an infrared thermometer. The significance of differences was assessed with either a two-sample t test or Welch's test, depending on the variances. The mean rises (number of times that the temperature rose above 10 °C) for each group of measurements were: for the 2mm drill, 4.8 °C (0/48) when cooled and 7.0 °C (8/48) when not cooled; with the 2.5mm drill, 5.2 °C (1/48) when cooled and 8.5 °C (17/48) when not cooled (2 mm canal); with the 3 mm drill, 3.3 °C when cooled (0/48) and 8.5 °C (18/24) when not cooled (2.5 mm canal); and with the 3.5 mm drill, 4.8 °C when cooled (0/24) and 9.4 °C when not cooled (10/23) (3 mm canal). The temperature rose significantly less with cooling at every step of the drilling sequence (p<0.001). We conclude that external cooling can maintain the intraosseous temperature within the safe range while drilling through an implant guide system, whereas drilling without irrigation can lead to temperatures that exceed the acceptable limit. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Direct-Drive Gas-Cooled Reactor Power System: Concept and Preliminary Testing

NASA Technical Reports Server (NTRS)

Wright, S. A.; Lipinski, R. J.; Godfroy, T. J.; Bragg-Sitton, S. M.; VanDyke, M. K.

2002-01-01

This paper describes the concept and preliminary component testing of a gas-cooled, UN-fueled, pin-type reactor which uses He/Xe gas that goes directly into a recuperated Brayton system to produce electricity for nuclear electric propulsion. This Direct-Drive Gas-Cooled Reactor (DDG) is designed to be subcritical under water or wet- sand immersion in case of a launch accident. Because the gas-cooled reactor can directly drive the Brayton turbomachinery, it is possible to configure the system such that there are no external surfaces or pressure boundaries that are refractory metal, even though the gas delivered to the turbine is 1144 K. The He/Xe gas mixture is a good heat transport medium when flowing, and a good insulator when stagnant. Judicious use of stagnant cavities as insulating regions allows transport of the 1144-K gas while keeping all external surfaces below 900 K. At this temperature super-alloys (Hastelloy or Inconel) can be used instead of refractory metals. Super-alloys reduce the technology risk because they are easier to fabricate than refractory metals, we have a much more extensive knowledge base on their characteristics, and, because they have a greater resistance to oxidation, system testing is eased. The system is also relatively simple in its design: no additional coolant pumps, heat exchanger, or freeze-thaw systems are required. Key to success of this concept is a good knowledge of the heat transfer between the fuel pins and the gas, as well as the pressure drop through the system. This paper describes preliminary testing to obtain this key information, as well as experience in demonstrating electrically heated testing of simulated reactor components.

Role of bacterial adhesion in the microbial ecology of biofilms in cooling tower systems.

PubMed

Liu, Yang; Zhang, Wei; Sileika, Tadas; Warta, Richard; Cianciotto, Nicholas P; Packman, Aaron

2009-01-01

The fate of the three heterotrophic biofilm forming bacteria, Pseudomonas aeruginosa, Klebsiella pneumoniae and Flavobacterium sp. in pilot scale cooling towers was evaluated both by observing the persistence of each species in the recirculating water and the formation of biofilms on steel coupons placed in each cooling tower water reservoir. Two different cooling tower experiments were performed: a short-term study (6 days) to observe the initial bacterial colonization of the cooling tower, and a long-term study (3 months) to observe the ecological dynamics with repeated introduction of the test strains. An additional set of batch experiments (6 days) was carried out to evaluate the adhesion of each strain to steel surfaces under similar conditions to those found in the cooling tower experiments. Substantial differences were observed in the microbial communities that developed in the batch systems and cooling towers. P. aeruginosa showed a low degree of adherence to steel surfaces both in batch and in the cooling towers, but grew much faster than K. pneumoniae and Flavobacterium in mixed-species biofilms and ultimately became the dominant organism in the closed batch systems. However, the low degree of adherence caused P. aeruginosa to be rapidly washed out of the open cooling tower systems, and Flavobacterium became the dominant microorganism in the cooling towers in both the short-term and long-term experiments. These results indicate that adhesion, retention and growth on solid surfaces play important roles in the bacterial community that develops in cooling tower systems.

Role of bacterial adhesion in the microbial ecology of biofilms in cooling tower systems

PubMed Central

Liu, Yang; Zhang, Wei; Sileika, Tadas; Warta, Richard; Cianciotto, Nicholas P.; Packman, Aaron

2009-01-01

The fate of the three heterotrophic biofilm forming bacteria, Pseudomonas aeruginosa, Klebsiella pneumoniae and Flavobacterium sp. in pilot scale cooling towers was evaluated both by observing the persistence of each species in the recirculating water and the formation of biofilms on steel coupons placed in each cooling tower water reservoir. Two different cooling tower experiments were performed: a short-term study (6 days) to observe the initial bacterial colonization of the cooling tower, and a long-term study (3 months) to observe the ecological dynamics with repeated introduction of the test strains. An additional set of batch experiments (6 days) was carried out to evaluate the adhesion of each strain to steel surfaces under similar conditions to those found in the cooling tower experiments. Substantial differences were observed in the microbial communities that developed in the batch systems and cooling towers. P. aeruginosa showed a low degree of adherence to steel surfaces both in batch and in the cooling towers, but grew much faster than K. pneumoniae and Flavobacterium in mixed-species biofilms and ultimately became the dominant organism in the closed batch systems. However, the low degree of adherence caused P. aeruginosa to be rapidly washed out of the open cooling tower systems, and Flavobacterium became the dominant microorganism in the cooling towers in both the short-term and long-term experiments. These results indicate that adhesion, retention and growth on solid surfaces play important roles in the bacterial community that develops in cooling tower systems. PMID:19177226

Monitoring results and analysis of thermal comfort conditions in experimental buildings for different heating systems and ventilation regimes during heating and cooling seasons

NASA Astrophysics Data System (ADS)

Gendelis, S.; Jakovičs, A.; Ratnieks, J.; Bandeniece, L.

2017-10-01

This paper focuses on the long-term monitoring of thermal comfort and discomfort parameters in five small test buildings equipped with different heating and cooling systems. Calculations of predicted percentage of dissatisfied people (PPD) index and discomfort factors are provided for the room in winter season running three different heating systems - electric heater, air-air heat pump and air-water heat pump, as well as for the summer cooling with split type air conditioning systems. It is shown that the type of heating/cooling system and its working regime has an important impact on thermal comfort conditions in observed room. Recommendations for the optimal operating regimes and choice of the heating system from the thermal comfort point of view are summarized.

Microbial fouling community analysis of the cooling water system of a nuclear test reactor with emphasis on sulphate reducing bacteria.

PubMed

Balamurugan, P; Joshi, M Hiren; Rao, T S

2011-10-01

Culture and molecular-based techniques were used to characterize bacterial diversity in the cooling water system of a fast breeder test reactor (FBTR). Techniques were selected for special emphasis on sulphate-reducing bacteria (SRB). Water samples from different locations of the FBTR cooling water system, in addition to biofilm scrapings from carbon steel coupons and a control SRB sample were characterized. Whole genome extraction of the water samples and SRB diversity by group specific primers were analysed using nested PCR and denaturing gradient gel electrophoresis (DGGE). The results of the bacterial assay in the cooling water showed that the total culturable bacteria (TCB) ranged from 10(3) to 10(5) cfu ml(-1); iron-reducing bacteria, 10(3) to 10(5) cfu ml(-1); iron oxidizing bacteria, 10(2) to 10(3) cfu ml(-1) and SRB, 2-29 cfu ml(-1). However, the counts of the various bacterial types in the biofilm sample were 2-3 orders of magnitude higher. SRB diversity by the nested PCR-DGGE approach showed the presence of groups 1, 5 and 6 in the FBTR cooling water system; however, groups 2, 3 and 4 were not detected. The study demonstrated that the PCR protocol influenced the results of the diversity analysis. The paper further discusses the microbiota of the cooling water system and its relevance in biofouling.

A Rapid Turnaround Cryogenic Detector Characterization System

NASA Technical Reports Server (NTRS)

Benford, Dominic j.; Dipirro, Michael J.; Forgione, Joshua B.; Jackson, Clifton E.; Jackson, Michael L.; Kogut, Al; Moseley, S. Harvey; Shirron, Peter J.

2004-01-01

Upcoming major NASA missions such as the Einstein Inflation Probe and the Single Aperture Far-Infrared Observatory require arrays of detectors with thousands of elements, operating at temperatures near l00 mK and sensitive to wavelengths from approx. 100 microns to approx. 3 mm. Such detectors represent a substantial enabling technology for these missions, and must be demonstrated soon in order for them to proceed. In order to make rapid progress on detector development, the cryogenic testing cycle must be made convenient and quick. We have developed a cryogenic detector characterization system capable of testing superconducting detector arrays in formats up to 8 x 32, read out by SQUID multiplexers. The system relies on the cooling of a two-stage adiabatic demagnetization refrigerator immersed in a liquid helium bath. This approach permits a detector to be cooled from 300K to 50 mK in about 4 hours, so that a test cycle begun in the morning will be over by the end of the day. Tine system is modular, with two identical immersible units, so that while one unit is cooling, the second can be reconfigured for the next battery of tests. We describe the design, construction, and performance of this cryogenic detector testing facility.

Evaluation of fiber reinforced polymers using active infrared thermography system with thermoelectric cooling modules

NASA Astrophysics Data System (ADS)

Chady, Tomasz; Gorący, Krzysztof

2018-04-01

Active infrared thermography is increasingly used for nondestructive testing of various materials. Properties of this method are creating a unique possibility to utilize it for inspection of composites. In the case of active thermography, an external energy source is usually used to induce a thermal contrast inside tested objects. The conventional heating methods (like halogen lamps or flash lamps) are utilized for this purpose. In this study, we propose to use a cooling unit. The proposed system consists of a thermal imaging infrared camera, which is used to observe the surface of the inspected specimen and a specially designed cooling unit with thermoelectric modules (the Peltier modules).

Solar heating and cooling system design and development

NASA Technical Reports Server (NTRS)

1978-01-01

The progress of the program during the sixth program quarter is reported. The program calls for the development and delivery of eight prototype solar heating and cooling systems for installation and operational test. The William O'Brien single-family heating system was installed and is operational. The New Castle single-family heating residence is under construction. The Kansas University (KU) system is in the final design stages. The 25 ton cooling subsystem for KU is the debugging stage. Pressure drops that were greater than anticipated were encountered. The 3 ton simulation work is being finalized and the design parameters for the Rankine system were determined from simulation output.

Hot melt adhesive pad surface attachment assembly concept for on-orbit operations

NASA Technical Reports Server (NTRS)

Progar, D. J.; Stein, B. A.

1984-01-01

The use of a hot melt adhesive concept to develop a Surface Attachment Assembly (SAA) for on-orbit attachment and detachment operations for the Manned Maneuvering Unit (MMU) was investigated. The concept involved impregnation of the hot melt adhesive into a fiberglass covered pad which contained electrical heating and thermoelectric cooling devices. The polyamide hot melt adhesive selected can be repeatedly heated to its melting point in a vacuum and provide good adhesion to various surfaces, i.e., reusable surface insulation tiles, metals, and composites, when cooled. After a series of adhesive screening tests, Jet-Melt 3746 was selected from a group of commercially available thermoplastic adhesive candidates which met or exceeded many of the criteria established for the SAA system. The SAA system was designed and fabricted with the goal of proving the concept with a working model rather than attempting to optimize all facets of the system. This system evolved by investigating alternate attachment concepts, designing and fabricating electronic systems to heat and cool the adhesive, and then fabricating electronic systems to heat and cool the adhesive, and then fabricating and testing two prototype full-size units.

Method and system for simulating heat and mass transfer in cooling towers

DOEpatents

Bharathan, Desikan; Hassani, A. Vahab

1997-01-01

The present invention is a system and method for simulating the performance of a cooling tower. More precisely, the simulator of the present invention predicts values related to the heat and mass transfer from a liquid (e.g., water) to a gas (e.g., air) when provided with input data related to a cooling tower design. In particular, the simulator accepts input data regarding: (a) cooling tower site environmental characteristics; (b) cooling tower operational characteristics; and (c) geometric characteristics of the packing used to increase the surface area within the cooling tower upon which the heat and mass transfer interactions occur. In providing such performance predictions, the simulator performs computations related to the physics of heat and mass transfer within the packing. Thus, instead of relying solely on trial and error wherein various packing geometries are tested during construction of the cooling tower, the packing geometries for a proposed cooling tower can be simulated for use in selecting a desired packing geometry for the cooling tower.

Evaluation of three commercial microclimate cooling systems

NASA Astrophysics Data System (ADS)

Cadarette, Bruce S.; Decristofano, Barry S.; Speckman, Karen N.; Sawka, Michael N.

1988-11-01

Three commercially available microclimate cooling systems were evaluated for their ability to reduce heat stress in men exercising in a hot environment while wearing high insulative, low permeability clothing. The cooling systems were: (1) ILC Dover Model 19 Coolvest (ILC) (2) LSSI Coolhead(LSSI), and (3) Thermacor Cooling vest (THERM). Endurance Time (ET), Heart Rate (HR), rectal temperature (Tre), mean skin temperature (TSK), Sweating Rate (SR), Rated Perceived Exertion (RPE) and Thermal Sensation (TS) were measured. The subjects self-terminated on all LSSI tests because of headaches. Statistical analyses were performed on data collected at 60 minutes to have values on all subjects. There were no differences in HR, Tre, SR or TS values among the cooling vests. The subjects' TSK was lower (P less than 0.05) for the LSSI than THERM: and RPE values were higher (P less than 0.05) for LSSI than the other two vests. These data suggest an improved physiological response to exercise heat stress with all three commercial systems with the greatest benefit in performance time provided by the ILC cooling system.

Physiologic and thermal responses of male and female patients with multiple sclerosis to head and neck cooling

NASA Technical Reports Server (NTRS)

Ku, Y. T.; Montgomery, L. D.; Wenzel, K. C.; Webbon, B. W.; Burks, J. S.

1999-01-01

Personal cooling systems are used to alleviate symptoms of multiple sclerosis and to prevent increased core temperature during daily activities. The objective of this study was to determine the thermal and physiologic responses of patients with multiple sclerosis to short-term maximal head and neck cooling. A Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used to cool the head and neck regions of 24 female and 26 male patients with multiple sclerosis in this study. The subjects, seated in an upright position at normal room temperature (approximately 22 degrees C), were cooled for 30 min by the liquid cooling garment, which was operated at its maximum cooling capacity. Oral, right, and left ear temperatures and cooling system parameters were logged manually every 5 min. Forearm, calf, chest, and rectal temperatures, heart rate, and respiration rate were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. This protocol was performed during the winter and summer to investigate the seasonal differences in the way patients with multiple sclerosis respond to head and neck cooling. No significant differences were found between the male and female subject group's mean rectal or oral temperature responses during any phase of the experiment. The mean oral temperature decreased significantly (P < 0.05) for both groups approximately 0.3 degrees C after 30 min of cooling and continued to decrease further (approximately 0.1-0.2 degrees C) for a period of approximately 15 min after removal of the cooling helmet. The mean rectal temperatures decreased significantly (P < 0.05) in both male and female subjects in the winter studies (approximately 0.2-0.3 degrees C) and for the male subjects during the summer test (approximately 0.2 degrees C). However, the rectal temperature of the female subjects did not change significantly during any phase of the summer test. These data indicate that head and neck cooling may, in general, be used to reduce the oral and body temperatures of both male and female patients with multiple sclerosis by the approximate amount needed for symptomatic relief as shown by other researchers. However, thermal response of patients with multiple sclerosis may be affected by gender and seasonal factors, which should be considered in the use of liquid cooling therapy.

Report on Lincoln Electric System gas turbine inlet air cooling. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ebeling, J.A.; Buecker, B.J.; Kitchen, B.J.

1993-12-01

As a result of increased electric power demand, the Lincoln Electric System (LES) of Lincoln, Nebraska (USA) decided to upgrade the generating capacity of their system. Based on capacity addition studies, the utility elected to improve performance of a GE MS7001B combustion turbine located at their Rokeby station. The turbine is used to meet summer-time peak loads, and as is common among combustion turbines, capacity declines as ambient air temperature rises. To improve the turbine capacity, LES decided to employ the proven technique of inlet air cooling, but with a novel approach: off-peak ice generation to be used for peak-loadmore » air cooling. EPRI contributed design concept definition and preliminary engineering. The American Public Power Association provided co-funding. Burns & McDonnell Engineering Company, under contract to Lincoln Electric System, provided detailed design and construction documents. LES managed the construction, start-up, and testing of the cooling system. This report describes the technical basis for the cooling system design, and it discusses combustion turbine performance, project economics, and potential system improvements. Control logic and P&ID drawings are also included. The inlet air cooling system has been available since the fall of 1991. When in use, the cooling system has increased turbine capacity by up to 17% at a cost of less than $200 per increased kilowatt of generation.« less

Experimental Study of an Aerospace Low Temperature Refrigerator Cooled by a Pulse-tube Cryocooler

NASA Astrophysics Data System (ADS)

Wen, Jiajia; Wu, Yinong; Zhang, Ankuo; Yang, Baoyu; Zhang, Hua; Chen, Xi; Chen, Haitao

Asingle-stage coaxial pulse tube cryocooler (PTC) has been designed, manufactured and tested at ShanghaiInstitute of Technical Physics (SITP), Chinese Academy of Sciences (CAS) for cooling an aerospace low temperature refrigerator (LTR), whose volume is 20 liters. The LTR system and the PTC system are introduced. Lots of simulations are carried out by CAD/FLUENT for verifying the LTR structure rationality and predicting the inside walls temperature uniformity. Some performance experiments of the LTR have been carried out and analyzedafter coupling with the PTC. The experimental results show that the PTC is capable of cooling the LTR to about average -100oC, so the PTC has a great potential for cooling aerospace LTRs. Some cooling curves are presented and discussed in detail for a thorough understanding of the LTR system.

Natural Convection Heat Transfer in a Rectangular Liquid Metal Pool With Bottom Heating and Top Cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Il S.; Yu, Yong H.; Son, Hyoung M.

2006-07-01

An experimental study is performed to investigate the natural convection heat transfer characteristics with subcooled coolant to create engineering database for basic applications in a lead alloy cooled reactor. Tests are performed in the ALTOS (Applied Liquid-metal Thermal Operation Study) apparatus as part of MITHOS (Metal Integrated Thermo Hydrodynamic Operation System). A relationship is determined between the Nusselt number Nu and the Rayleigh number Ra in the liquid metal rectangular pool. Results are compared with correlations and experimental data in the literature. Given the similar Ra condition, the present test results for Nu of the liquid metal pool with topmore » subcooling are found to be similar to those predicted by the existing correlations or experiments. The current test results are utilized to develop natural convection heat transfer correlations applicable to low Prandtl number Pr fluids that are heated from below and cooled by the external coolant above. Results from this study are slated to be used in designing BORIS (Battery Optimized Reactor Integral System), a small lead cooled modular fast reactor for deployment at remote sites cycled with MOBIS (Modular Optimized Brayton Integral System) for electricity generation, tied with NAVIS (Naval Application Vessel Integral System) for ship propulsion, joined with THAIS (Thermochemical Hydrogen Acquisition Integral System) for hydrogen production, and coupled with DORIS (Desalination Optimized Reactor Integral System) for seawater desalination. Tests are performed with Wood's metal (Pb-Bi-Sn-Cd) filling a rectangular pool whose lower surface is heated and upper surface cooled by forced convection of water. The test section is 20 cm long, 11.3 cm high and 15 cm wide. The simulant has a melting temperature of 78 deg. C. The constant temperature and heat flux condition was realized for the bottom heating once the steady state had been met. The test parameters include the heated bottom surface temperature of the liquid metal pool, the input power to the bottom surface of the section, and the coolant temperature. (authors)« less

Cryogenics for the MuCool Test Area (MTA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Darve, Christine; Norris, Barry; Pei, Liu-Jin

2005-09-01

MuCool Test Area (MTA) is a complex of buildings at Fermi National Accelerator Laboratory, which are dedicated to operate components of a cooling cell to be used for Muon Collider and Neutrino Factory R&D. The long-term goal of this facility is to test ionization cooling principles by operating a 25-liter liquid hydrogen (LH{sub 2}) absorber embedded in a 5 Tesla superconducting solenoid magnet. The MTA solenoid magnet will be used with RF cavities exposed to a high intensity beam. Cryogens used at the MTA include LHe, LN{sub 2} and LH{sub 2}. The latter dictates stringent system design for hazardous locations.more » The cryogenic plant is a modified Tevatron refrigerator based on the Claude cycle. The implementation of an in-house refrigerator system and two 300 kilowatt screw compressors is under development. The helium refrigeration capacity is 500 W at 14 K. In addition the MTA solenoid magnet will be batch-filled with LHe every 2 days using the same cryo-plant. This paper reviews cryogenic systems used to support the Muon Collider and Neutrino Factory R&D programs and emphasizes the feasibility of handling cryogenic equipment at MTA in a safe manner.« less

Cryogenics for the MuCool Test Area (MTA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Darve, Christine; Norris, Barry; Pei, Liujin

2006-03-20

MuCool Test Area (MTA) is a complex of buildings at Fermi National Accelerator Laboratory, which are dedicated to operate components of a cooling cell to be used for Muon Collider and Neutrino Factory R and D. The long-term goal of this facility is to test ionization cooling principles by operating a 25-liter liquid hydrogen (LH2) absorber embedded in a 5 Tesla superconducting solenoid magnet. The MTA solenoid magnet will be used with RF cavities exposed to a high intensity beam. Cryogens used at the MTA include LHe, LN2 and LH2. The latter dictates stringent system design for hazardous locations. Themore » cryogenic plant is a modified Tevatron refrigerator based on the Claude cycle. The implementation of an in-house refrigerator system and two 300 kilowatt screw compressors is under development. The helium refrigeration capacity is 500 W at 14 K. In addition the MTA solenoid magnet will be batch-filled with LHe every 2 days using the same cryo-plant. This paper reviews cryogenic systems used to support the Muon Collider and Neutrino Factory R and D programs and emphasizes the feasibility of handling cryogenic equipment at MTA in a safe manner.« less

Development, testing, and certification of Owens-Illinois model SEC-601 solar energy collector system

NASA Technical Reports Server (NTRS)

Parker, J. C.

1979-01-01

The final results are presented of the additional development work on the existing air-cooled solar energy collector subsystem for use with solar heating and cooling systems. The report discusses the intended use of the final report, describes the deliverable end items, lists program objectives, relates how they were accomplished, deals with problems encountered during fabrication and testing, and includes a certification statement of performance. The report shows that the products developed are marketable and suitable for public use.

''Football'' test coil: a simulated service test of internally-cooled, cabled superconductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marston, P.G.; Iwasa, Y.; Thome, R.J.

Internally-cooled, cabled superconductor, (ICCS), appears from small-scale tests to be a viable alternative to pool-boiling cooled superconductors for large superconducting magnets. Potential advantages may include savings in helium inventory, smaller structure and ease of fabrication. Questions remain, however, about the structural performance of these systems. The ''football'' test coil has been designed to simulate the actual ''field-current-stress-thermal'' operating conditions of a 25 ka ICCS in a commercial scale MHD magnet. The test procedure will permit demonstration of the 20 year cyclic life of such a magnet in less than 20 days. This paper describes the design, construction and test ofmore » that coil which is wound of copper-stabilized niobium-titanium cable in steel conduit. 2 refs.« less

Energy efficient engine high-pressure turbine component rig performance test report

NASA Technical Reports Server (NTRS)

Leach, K. P.

1983-01-01

A rig test of the cooled high-pressure turbine component for the Energy Efficient Engine was successfully completed. The principal objective of this test was to substantiate the turbine design point performance as well as determine off-design performance with the interaction of the secondary flow system. The measured efficiency of the cooled turbine component was 88.5 percent, which surpassed the rig design goal of 86.5 percent. The secondary flow system in the turbine performed according to the design intent. Characterization studies showed that secondary flow system performance is insensitive to flow and pressure variations. Overall, this test has demonstrated that a highly-loaded, transonic, single-stage turbine can achieve a high level of operating efficiency.

Correction analysis for a supersonic water cooled total temperature probe tested to 1370 K

NASA Technical Reports Server (NTRS)

Lagen, Nicholas T.; Seiner, John M.

1991-01-01

The authors address the thermal analysis of a water cooled supersonic total temperature probe tested in a Mach 2 flow, up to 1366 K total temperature. The goal of this experiment was the determination of high-temperature supersonic jet mean flow temperatures. An 8.99 cm exit diameter water cooled nozzle was used in the tests. It was designed for exit Mach 2 at 1366 K exit total temperature. Data along the jet centerline were obtained for total temperatures of 755 K, 1089 K, and 1366 K. The data from the total temperature probe were affected by the water coolant. The probe was tested through a range of temperatures between 755 K and 1366 K with and without the cooling system turned on. The results were used to develop a relationship between the indicated thermocouple bead temperature and the freestream total temperature. The analysis and calculated temperatures are presented.

Technical note on results of production test IP-628-AI: Crosstie flow test and flushing calibration, and the earlier production tests IP-573-AI and IP-499-AI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, S.S.

1964-06-15

A series of three experimental tests was conducted on the operation and adequacy of the K-Reactors` third, or last-ditch, cooling system. The first test showed considerable line corrosion the second test was performed directly after line cleaning, and the third test showed a significant amount of additional line corrosion after only nine months of service. The present cooling adequacy of this last-ditch system at the KE and KW reactors is summarized these show the power levels for which we have adequate last-ditch cooling as a function of the crosstie coolant temperature. These figures include the effects of increasing the numbermore » of pumps that remain in operation at the other K-Reactor, and various other operating or emergency conditions. These curves are for diesel pump speeds of 750 rpm which are planned for June of this year. In these figures the crosstie temperature is assumed to be a conservative 5{degrees}C above the process water inlet temperature.« less

Electronic cooling design and test validation

NASA Astrophysics Data System (ADS)

Murtha, W. B.

1983-07-01

An analytical computer model has been used to design a counterflow air-cooled heat exchanger according to the cooling, structural and geometric requirements of a U.S. Navy shipboard electronics cabinet, emphasizing high reliability performance through the maintenance of electronic component junction temperatures lower than 110 C. Environmental testing of the design obtained has verified that the analytical predictions were conservative. Model correlation to the test data furnishes an upgraded capability for the evaluation of tactical effects, and has established a two-orders of magnitude growth potential for increased electronics capabilities through enhanced heat dissipation. Electronics cabinets of this type are destined for use with Vertical Launching System-type combatant vessel magazines.

High power cable with internal water cooling 400 kV

NASA Astrophysics Data System (ADS)

Rasquin, W.; Harjes, B.

1982-08-01

Due to the concentration of electricity production in large power plants, the need of higher power transmissions, and the protection of environment, developement of a 400 kV water cooled cable in the power range of 1 to 5 GVA was undertaken. The fabrication and testing of equipment, engineering of cable components, fabrication of a test cable, development of cable terminal laboratory, testing of test cable, field testing of test cable, fabrication of industrial cable laboratory, testing of industrial cable, field testing of industrial cable, and system analysis for optimization were prepared. The field testing was impossible to realize. However, it is proved that a cable consisting of an internal stainless steel water cooled tube, covered by stranded copper profiles, insulated with heavy high quality paper, and protected by an aluminum cover can be produced, withstand tests accordingly to IEC/VDE recommendations, and is able to fulfill all exploitation conditions.

Experimental study on natural circulation precooling of cryogenic pump system with gas phase inlet reflux configuration

NASA Astrophysics Data System (ADS)

Chen, G. B.; Zhong, Y. K.; Zheng, X. L.; Li, Q. F.; Xie, X. M.; Gan, Z. H.; Huang, Y. H.; Tang, K.; Kong, B.; Qiu, L. M.

2003-12-01

A novel gas-phase inlet configuration in the natural circulation system instead of the liquid-phase inlet is introduced to cool down a cryogenic pump system from room temperature to cryogenic temperatures, effectively. The experimental apparatus is illustrated and test process is described. Heat transfer and pressure drop data during the cool-down process are recorded and portrayed. By contrast with liquid-phase inlet configuration, experimental results demonstrate that the natural circulation with the gas-phase inlet configuration is an easier and more controllable way to cool down the pump system and maintain it at cryogenic temperatures.

Subcontracted activities related to TES for building heating and cooling

NASA Technical Reports Server (NTRS)

Martin, J.

1980-01-01

The subcontract program elements related to thermal energy storage for building heating and cooling systems are outlined. The following factors are included: subcontracts in the utility load management application area; life and stability testing of packaged low cost energy storage materials; and development of thermal energy storage systems for residential space cooling. Resistance storage heater component development, demonstration of storage heater systems for residential applications, and simulation and evaluation of latent heat thermal energy storage (heat pump systems) are also discussed. Application of thermal energy storage for solar application and twin cities district heating are covered including an application analysis and technology assessment of thermal energy storage.

The design of aircraft brake systems, employing cooling to increase brake life

NASA Technical Reports Server (NTRS)

Scaringe, R. P.; Ho, T. L.; Peterson, M. B.

1975-01-01

A research program was initiated to determine the feasibility of using cooling to increase brake life. An air cooling scheme was proposed, constructed and tested with various designs. Straight and curved slotting of the friction material was tested. A water cooling technique, similar to the air cooling procedure, was evaluated on a curved slotted rotor. Also investigated was the possibility of using a phase-change material within the rotor to absorb heat during braking. Various phase-changing materials were tabulated and a 50%, (by weight) LiF - BeF2 mixing was chosen. It was shown that corrosion was not a problem with this mixture. A preliminary design was evaluated on an actual brake. Results showed that significant improvements in lowering the surface temperature of the brake occurred when air or water cooling was used in conjunction with curved slotted rotors.

Solar heater/cooler for mass market

NASA Technical Reports Server (NTRS)

1981-01-01

Report describes project to design, build, and test simple and affordable solar systems. Four combinations of heating, cooling, and domestic hot water supply systems were developed and installed. Test sites, plan for systems and components, and performance are discussed; text is complimented by detailed drawings and test data.

Analysis and Design of the NASA Langley Cryogenic Pressure Box

NASA Technical Reports Server (NTRS)

Glass, David E.; Stevens, Jonathan C.; Vause, R. Frank; Winn, Peter M.; Maguire, James F.; Driscoll, Glenn C.; Blackburn, Charles L.; Mason, Brian H.

1999-01-01

A cryogenic pressure box was designed and fabricated for use at NASA Langley Research Center (LaRC) to subject 72 in. x 60 in. curved panels to cryogenic temperatures and biaxial tensile loads. The cryogenic pressure box is capable of testing curved panels down to -423 F (20K) with 54 psig maximum pressure on the concave side, and elevated temperatures and atmospheric pressure on the convex surface. The internal surface of the panel is cooled by high pressure helium as that is cooled to -423 F by liquid helium heat exchangers. An array of twelve independently controlled fans circulate the high pressure gaseous helium to provide uniform cooling on the panel surface. The load introduction structure, consisting of four stainless steel load plates and numerous fingers attaching the load plates to the test panel, is designed to introduce loads into the test panel that represent stresses that will he observed in the actual tank structure. The load plates are trace cooled with liquid nitrogen to reduce thermal gradients that may result in bending the load plates, and thus additional stresses in the test panel. The design of the cryogenic systems, load introduction structure, and control system are discussed in this report.

Compliant Metal Enhanced Convection Cooled Reverse-Flow Annular Combustor

NASA Technical Reports Server (NTRS)

Paskin, Marc D.; Acosta, Waldo A.

1994-01-01

A joint Army/NASA program was conducted to design, fabricate, and test an advanced, reverse-flow, small gas turbine combustor using a compliant metal enhanced (CME) convection wall cooling concept. The objectives of this effort were to develop a design method (basic design data base and analysis) for the CME cooling technique and tben demonstrate its application to an advanced cycle, small, reverse-flow combustor with 3000 F (1922 K) burner outlet temperature (BOT). The CME concept offers significant improvements in wall cooling effectiveness resulting in a large reduction in cooling air requirements. Therefore, more air is available for control of burner outlet temperature pattern in addition to the benefit of improved efficiency, reduced emissions, and smoke levels. Rig test results demonstrated the benefits and viability of the CME concept meeting or exceeding the aerothermal performance and liner wall temperature characteristics of similar lower temperature-rise combustors, achieving 0.15 pattern factor at 3000 F (1922 K) BOT, while utilizing approximately 80 percent less cooling air than conventional, film-cooled combustion systems.

Research on hypersonic aircraft using pre-cooled turbojet engines

NASA Astrophysics Data System (ADS)

Taguchi, Hideyuki; Kobayashi, Hiroaki; Kojima, Takayuki; Ueno, Atsushi; Imamura, Shunsuke; Hongoh, Motoyuki; Harada, Kenya

2012-04-01

Systems analysis of a Mach 5 class hypersonic aircraft is performed. The aircraft can fly across the Pacific Ocean in 2 h. A multidisciplinary optimization program for aerodynamics, structure, propulsion, and trajectory is used in the analysis. The result of each element model is improved using higher accuracy analysis tools. The aerodynamic performance of the hypersonic aircraft is examined through hypersonic wind tunnel tests. A thermal management system based on the data of the wind tunnel tests is proposed. A pre-cooled turbojet engine is adopted as the propulsion system for the hypersonic aircraft. The engine can be operated continuously from take-off to Mach 5. This engine uses a pre-cooling cycle using cryogenic liquid hydrogen. The high temperature inlet air of hypersonic flight would be cooled by the same liquid hydrogen used as fuel. The engine is tested under sea level static conditions. The engine is installed on a flight test vehicle. Both liquid hydrogen fuel and gaseous hydrogen fuel are supplied to the engine from a tank and cylinders installed within the vehicle. The designed operation of major components of the engine is confirmed. A large amount of liquid hydrogen is supplied to the pre-cooler in order to make its performance sufficient for Mach 5 flight. Thus, fuel rich combustion is adopted at the afterburner. The experiments are carried out under the conditions that the engine is mounted upon an experimental airframe with both set up either horizontally or vertically. As a result, the operating procedure of the pre-cooled turbojet engine is demonstrated.

An Experimental Test Facility to Support Development of the Fluoride Salt Cooled High Temperature Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoder Jr, Graydon L; Aaron, Adam M; Cunningham, Richard Burns

2014-01-01

The need for high-temperature (greater than 600 C) energy exchange and delivery systems is significantly increasing as the world strives to improve energy efficiency and develop alternatives to petroleum-based fuels. Liquid fluoride salts are one of the few energy transport fluids that have the capability of operating at high temperatures in combination with low system pressures. The Fluoride Salt-Cooled High-Temperature Reactor design uses fluoride salt to remove core heat and interface with a power conversion system. Although a significant amount of experimentation has been performed with these salts, specific aspects of this reactor concept will require experimental confirmation during themore » development process. The experimental facility described here has been constructed to support the development of the Fluoride Salt Cooled High Temperature Reactor concept. The facility is capable of operating at up to 700 C and incorporates a centrifugal pump to circulate FLiNaK salt through a removable test section. A unique inductive heating technique is used to apply heat to the test section, allowing heat transfer testing to be performed. An air-cooled heat exchanger removes added heat. Supporting loop infrastructure includes a pressure control system; trace heating system; and a complement of instrumentation to measure salt flow, temperatures, and pressures around the loop. The initial experiment is aimed at measuring fluoride salt heat transfer inside a heated pebble bed similar to that used for the core of the pebble bed advanced high-temperature reactor. This document describes the details of the loop design, auxiliary systems used to support the facility, the inductive heating system, and facility capabilities.« less

Corrosion inhibitors for solar heating and cooling systems

NASA Technical Reports Server (NTRS)

Humphries, T. S.; Deramus, G. E., Jr.

1977-01-01

Problems dealing with corrosion and corrosion protection of solar heating and cooling systems are discussed. A test program was conducted to find suitable and effective corrosion inhibitors for systems employing either water or antifreeze solutions for heat transfer and storage. Aluminum-mild-steel-copper-stainless steel assemblies in electrical contact were used to simulate a multimetallic system which is the type most likely to be employed. Several inhibitors show promise for this application.

Dynamic Response Testing in an Electrically Heated Reactor Test Facility

NASA Astrophysics Data System (ADS)

Bragg-Sitton, Shannon M.; Morton, T. J.

2006-01-01

Non-nuclear testing can be a valuable tool in the development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and fueled nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe (HP) cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system. Reactivity feedback calculations were then based on a bulk reactivity feedback coefficient and measured average core temperature. This paper presents preliminary results from similar dynamic testing of a direct drive gas cooled reactor system (DDG), demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. Although the HP and DDG designs both utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility. Planned system upgrades to allow implementation of higher fidelity dynamic testing are also discussed. Proposed DDG testing will utilize a higher fidelity point kinetics model to control core power transients, and reactivity feedback will be based on localized feedback coefficients and several independent temperature measurements taken within the core block. This paper presents preliminary test results and discusses the methodology that will be implemented in follow-on DDG testing and the additional instrumentation required to implement high fidelity dynamic testing.

Influence of collector heat capacity and internal conditions of heat exchanger on cool-down process of small gas liquefier

NASA Astrophysics Data System (ADS)

Saberimoghaddam, Ali; Bahri Rasht Abadi, Mohammad Mahdi

2018-01-01

Joule-Thomson cooling systems are commonly used in gas liquefaction. In small gas liquefiers, transient cool-down time is high. Selecting suitable conditions for cooling down process leads to decrease in time and cost. In the present work, transient thermal behavior of Joule-Thomson cooling system including counter current helically coiled tube in tube heat exchanger, expansion valve, and collector was studied using experimental tests and simulations. The experiments were performed using small gas liquefier and nitrogen gas as working fluid. The heat exchanger was thermally studied by experimental data obtained from a small gas liquefier. In addition, the simulations were performed using experimental data as variable boundary conditions. A comparison was done between presented and conventional methods. The effect of collector heat capacity and convection heat transfer coefficient inside the tubes on system performance was studied using temperature profiles along the heat exchanger.

Evaluation of two cooling systems under a firefighter coverall.

PubMed

Teunissen, Lennart P J; Wang, Li-Chu; Chou, Shih-Nung; Huang, Chin-Hsien; Jou, Gwo-Tsuen; Daanen, Hein A M

2014-11-01

Firemen often suffer from heat strain. This study investigated two chest cooling systems for use under a firefighting suit. In nine male subjects, a vest with water soaked cooling pads and a vest with water perfused tubes were compared to a control condition. Subjects performed 30 min walking and 10 min recovery in hot conditions, while physiological and perceptual parameters were measured. No differences were observed in heart rate and rectal temperature, but scapular skin temperature and fluid loss were lower using the perfused vest. Thermal sensation was cooler for the perfused vest than for the other conditions, while the cool pad vest felt initially cooler than control. However, comfort and RPE scores were similar. We conclude that the cooling effect of both tested systems, mainly providing a (temporally) cooler thermal sensation, was limited and did not meet the expectations. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Design Report for the ½ Scale Air-Cooled RCCS Tests in the Natural convection Shutdown heat removal Test Facility (NSTF)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lisowski, D. D.; Farmer, M. T.; Lomperski, S.

The Natural convection Shutdown heat removal Test Facility (NSTF) is a large scale thermal hydraulics test facility that has been built at Argonne National Laboratory (ANL). The facility was constructed in order to carry out highly instrumented experiments that can be used to validate the performance of passive safety systems for advanced reactor designs. The facility has principally been designed for testing of Reactor Cavity Cooling System (RCCS) concepts that rely on natural convection cooling for either air or water-based systems. Standing 25-m in height, the facility is able to supply up to 220 kW at 21 kW/m 2 tomore » accurately simulate the heat fluxes at the walls of a reactor pressure vessel. A suite of nearly 400 data acquisition channels, including a sophisticated fiber optic system for high density temperature measurements, guides test operations and provides data to support scaling analysis and modeling efforts. Measurements of system mass flow rate, air and surface temperatures, heat flux, humidity, and pressure differentials, among others; are part of this total generated data set. The following report provides an introduction to the top level-objectives of the program related to passively safe decay heat removal, a detailed description of the engineering specifications, design features, and dimensions of the test facility at Argonne. Specifications of the sensors and their placement on the test facility will be provided, along with a complete channel listing of the data acquisition system.« less

Commercialization of Medium Voltage HTS Triax TM Cable Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knoll, David

2012-12-31

The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed themore » market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.« less

MODELING THE AMBIENT CONDITION EFFECTS OF AN AIR-COOLED NATURAL CIRCULATION SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Rui; Lisowski, Darius D.; Bucknor, Matthew

The Reactor Cavity Cooling System (RCCS) is a passive safety concept under consideration for the overall safety strategy of advanced reactors such as the High Temperature Gas-Cooled Reactor (HTGR). One such variant, air-cooled RCCS, uses natural convection to drive the flow of air from outside the reactor building to remove decay heat during normal operation and accident scenarios. The Natural convection Shutdown heat removal Test Facility (NSTF) at Argonne National Laboratory (“Argonne”) is a half-scale model of the primary features of one conceptual air-cooled RCCS design. The facility was constructed to carry out highly instrumented experiments to study the performancemore » of the RCCS concept for reactor decay heat removal that relies on natural convection cooling. Parallel modeling and simulation efforts were performed to support the design, operation, and analysis of the natural convection system. Throughout the testing program, strong influences of ambient conditions were observed in the experimental data when baseline tests were repeated under the same test procedures. Thus, significant analysis efforts were devoted to gaining a better understanding of these influences and the subsequent response of the NSTF to ambient conditions. It was determined that air humidity had negligible impacts on NSTF system performance and therefore did not warrant consideration in the models. However, temperature differences between the building exterior and interior air, along with the outside wind speed, were shown to be dominant factors. Combining the stack and wind effects together, an empirical model was developed based on theoretical considerations and using experimental data to correlate zero-power system flow rates with ambient meteorological conditions. Some coefficients in the model were obtained based on best fitting the experimental data. The predictive capability of the empirical model was demonstrated by applying it to the new set of experimental data. The empirical model was also implemented in the computational models of the NSTF using both RELAP5-3D and STARCCM+ codes. Accounting for the effects of ambient conditions, simulations from both codes predicted the natural circulation flow rates very well.« less

Progress of a room temperature electron cyclotron resonance ion source using evaporative cooling technology at Institute of Modern Physics.

PubMed

Lu, W; Xiong, B; Zhang, X Z; Sun, L T; Feng, Y C; Ma, B H; Guo, S Q; Cao, R; Ruan, L; Zhao, H W

2014-02-01

A new room temperature ECR ion source, Lanzhou Electron Cyclotron Resonance ion source No. 4 (LECR4, previously named DRAGON), is under intense construction at Institute of Modern Physics. LECR4 is designed to operate with 18 GHz microwave frequency. The maximum axial magnetic fields are 2.3 T at injection and 1.3 T at extraction, and the radial field at the plasma chamber wall of 76 mm inner diameter is 1.0-1.2 T. One of the unique features for LECR4 is that its axial solenoids are winded with solid square copper wires which are immersed in a kind of special evaporative cooling medium for cooling purpose. Till now, a prototype of the cooling system has been successfully constructed and tested, which has demonstrated that the cooling efficiency of the designed system could meet the requirements of LECR4 under the routine operation conditions. All the main components of the ion source have been completed. Assembly and commissioning is ongoing. The latest developments and test results will be presented in this paper.

A Si/Glass Bulk-Micromachined Cryogenic Heat Exchanger for High Heat Loads: Fabrication, Test, and Application Results.

PubMed

Zhu, Weibin; White, Michael J; Nellis, Gregory F; Klein, Sanford A; Gianchandani, Yogesh B

2010-02-01

This paper reports on a micromachined Si/glass stack recuperative heat exchanger with in situ temperature sensors. Numerous high-conductivity silicon plates with integrated platinum resistance temperature detectors (Pt RTDs) are stacked, alternating with low-conductivity Pyrex spacers. The device has a 1 x 1-cm(2) footprint and a length of up to 3.5 cm. It is intended for use in Joule-Thomson (J-T) coolers and can sustain pressure exceeding 1 MPa. Tests at cold-end inlet temperatures of 237 K-252 K show that the heat exchanger effectiveness is 0.9 with 0.039-g/s helium mass flow rate. The integrated Pt RTDs present a linear response of 0.26%-0.30%/K over an operational range of 205 K-296 K but remain usable at lower temperatures. In self-cooling tests with ethane as the working fluid, a J-T system with the heat exchanger drops 76.1 K below the inlet temperature, achieving 218.7 K for a pressure of 835.8 kPa. The system reaches 200 K in transient state; further cooling is limited by impurities that freeze within the flow stream. In J-T self-cooling tests with an external heat load, the system reaches 239 K while providing 1 W of cooling. In all cases, there is an additional parasitic heat load estimated at 300-500 mW.

Variable Gravity Effects on the Cooling Performance of a Single Phase Confined Spray

NASA Technical Reports Server (NTRS)

Michalak, Travis; Yerkes, Kirk; Baysinger, Karri; McQuillen, John

2005-01-01

The objective of this paper is to discuss the testing of a spray cooling experiment designed to be flown on NASA's KC-135 Reduced Gravity Testing Platform. Spray cooling is an example of a thermal management technique that may be utilized in high flux heat acquisition and high thermal energy transport concepts. Many researchers have investigated the utility of spray cooling for the thermal management of devices generating high heat fluxes. However, there has been little research addressing the physics and ultimate performance of spray cooling in a variable gravity environment. An experimental package, consisting of a spray chamber coupled to a fluid delivery loop system, was fabricated for variable gravity flight tests. The spray chamber contains two opposing nozzles spraying on target Indium Tin Oxide (ITO) heaters. These heaters are mounted on glass pedestals, which are part of a sump system to remove unconstrained liquid from the test chamber. Liquid is collected in the sumps and returned to the fluid delivery loop. Thermocouples mounted in and around the pedestals are used to determine both the heat loss through the underside of the IT0 heater and the heat extracted by the spray. A series of flight tests were carried out aboard the KC-135, utilizing the ability of the aircraft to produce various gravity conditions. During the flight tests, for a fixed flow rate, heat input was varied at 20, 30, 50, and 80W with variable gravities of 0.01, 0.16, 0.36, and 1.8g. Flight test data was compared to terrestrial baseline data in addition to analytical and numerical solutions to evaluate the heat transfer in the heater and support structure . There were significant differences observed in the spray cooling performance as a result of variable gravity conditions and heat inputs. In general, the Nussult number at the heater surface was found to increase with decreasing gravity conditions for heat loads greater than 30W.

Field experience with aquifer thermal energy storage

NASA Astrophysics Data System (ADS)

Kannberg, L. D.

1987-11-01

Aquifer thermal energy storage (ATES) has the potential to provide storage for large-scale building heating and cooling at many sites in the US. However, implementation requires careful attention to site geohydraulic and geochemical characteristics. Field tests in the US have shown the over 60% of the heat injected at temperatures over 100 C can be recovered on a seasonal cycle. Similarly, aquifer storage of shilled ground water can provide building cooling with annual cooling electrical energy reductions of over 50% and a reduction in summer peak cooling electrical usage by as much as a factor of 20. A number of projects have been built and operated around the world. China has installed numerous ATES systems in many major cities. Installations in Europe and Scandinavia are almost exclusively low-temperature heat storage systems that use heat pumps. Two high-temperature systems (over 100 C) are in operation or undergoing preliminary testing: one in Denmark, the other in France. Heat ATES often requires water treatment to prevent precipitation of calcium and magnesium carbonates. At some sites, consideration of other geochemical and microbiological issues (such as iron bacteria) must be resolved.

Liquid Nitrogen Zero Boiloff Testing

NASA Technical Reports Server (NTRS)

Plachta, David; Feller, Jeffrey; Johnson, Wesley; Robinson, Craig

2017-01-01

Cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) are a part of NASAs future space exploration due to their high specific impulse for rocket motors of upper stages suitable for transporting 10s to 100s of metric tons of payload mass to destinations outside of low earth orbit and for their return. However, the low storage temperatures of LH2 and LO2 cause substantial boil-off losses for missions with durations greater than several months. These losses can be eliminated by incorporating high performance cryocooler technology to intercept heat load to the propellant tanks and modulating the cryocooler to control tank pressure. The active thermal control technology being developed by NASA is the reverse turbo-Brayton cycle cryocooler and its integration to the propellant tank through a distributed cooling tubing network coupled to the tank wall. This configuration was recently tested at NASA Glenn Research Center, in a vacuum chamber and cryo-shroud that simulated the essential thermal aspects of low Earth orbit, its vacuum and temperature. Testing consisted of three passive tests with the active cryo-cooler system off, and 7 active tests, with the cryocooler powered up. The test matrix included zero boil-off tests performed at 90 full and 25 full, and several demonstrations at excess cooling capacity and reduced cooling capacity. From this, the tank pressure response with varied cryocooler power inputs was determined. This test series established that the active cooling system integrated with the propellant tank eliminated boil-off and robustly controlled tank pressure.

Thermally Simulated Testing of a Direct-Drive Gas-Cooled Nuclear Reactor

NASA Technical Reports Server (NTRS)

Godfroy, Thomas; Bragg-Sitton, Shannon; VanDyke, Melissa

2003-01-01

This paper describes the concept and preliminary component testing of a gas-cooled, UN-fueled, pin-type reactor which uses He/Xe gas that goes directly into a recuperated Brayton system to produce electricity for nuclear electric propulsion. This Direct-Drive Gas-Cooled Reactor (DDG) is designed to be subcritical under water or wet-sand immersion in case of a launch accident. Because the gas-cooled reactor can directly drive the Brayton turbomachinery, it is possible to configure the system such that there are no external surfaces or pressure boundaries that are refractory metal, even though the gas delivered to the turbine is 1144 K. The He/Xe gas mixture is a good heat transport medium when flowing, and a good insulator when stagnant. Judicious use of stagnant cavities as insulating regions allows transport of the 1144-K gas while keeping all external surfaces below 900 K. At this temperature super-alloys (Hastelloy or Inconel) can be used instead of refractory metals. Super-alloys reduce the technology risk because they are easier to fabricate than refractory metals, we have a much more extensive knowledge base on their characteristics, and, because they have a greater resistance to oxidation, system testing is eased. The system is also relatively simple in its design: no additional coolant pumps, heat exchanger, or freeze-thaw systems are required. Key to success of this concept is a good knowledge of the heat transfer between the fuel pins and the gas, as well as the pressure drop through the system. This paper describes preliminary testing to obtain this key information, as well as experience in demonstrating electrical thermal simulation of reactor components and concepts.

Corrosion inhibitors for solar-heating and cooling

NASA Technical Reports Server (NTRS)

Humphries, T. S.

1979-01-01

Report describes results of tests conducted to evaluate abilities of 12 candidate corrosion inhibitors to protect aluminum, steel, copper, or stainless steel at typical conditions encountered in solar heating and cooling systems. Inhibitors are based on sodium salts including nitrates, borates, silicates, and phosphates.

The design and testing of a cooling system using mixed solid cryogen for a portable superconducting magnetic energy storage system

NASA Astrophysics Data System (ADS)

Kim, K. L.; Song, J. B.; Choi, J. H.; Kim, S. H.; Y Koh, D.; Seong, K. C.; Chang, H. M.; Lee, H. G.

2010-12-01

A cooling system that uses solid nitrogen (SN2) as an effective heat capacity enhancer was recently introduced to enhance the thermal stability of the HTS SMES. Since SN2 has a large enthalpy with minimal weight, it enables a portable system by increasing the recooling to recooling time period (RRTP). However, contact between the SN2 and HTS SMES magnet can be broken by repeated thermal disturbances (thermal 'dry-out' phenomena). Therefore, it is essential to improve thermal contact to allow full use of the heat capacity of SN2. This study evaluated the effect of using a mixture containing SN2 and a small amount of a liquid cryogen as a cooling system in the HTS SMES system. The performance of the cooling system was evaluated using the mixed cryogen and compared with that of SN2 alone. In addition, the role of liquid neon (Ne) as a heat exchanger between SN2 and the HTS SMES magnet is discussed.

Wright R–2600–8 Engine in the Engine Propeller Research Building

NASA Image and Video Library

1943-03-21

A Wright Aeronautical R–2600 Cyclone piston engine installed in the Engine Propeller Research Building, or Prop House, at the National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research Laboratory. The R–2600 was among the most powerful engines that emerged during World War II. The engine, which was developed for commercial applications in 1939, was used to power the North American B–25 bomber and several other midsize military aircraft. The higher altitudes required by the military caused problems with the engine's cooling and fuel systems. The military requested that the Aircraft Engine Research Laboratory analyze the performance of the R–2600, improve its cooling system, and reduce engine knock. The NACA researchers subjected the engine to numerous tests in its Prop House. The R–2600 was the subject of the laboratory's first technical report, which was written by members of the Fuels and Lubricants Division. The Prop House contained soundproof test cells in which piston engines and propellers were mounted and operated at high powers. Electrically driven fans drew air through ducts to create a stream of cooling air over the engines. Researchers tested the performance of fuels, turbochargers, water-injection and cooling systems here during World War II. The facility was also investigated a captured German V–I buzz bomb during the war.

Improvements and Performance of the Fermilab Solenoid Test Facility

DOE PAGES

Orris, Darryl; Arnold, Don; Brandt, Jeffrey; ...

2017-06-01

Here, the Solenoid Test Facility at Fermilab was built using a large vacuum vessel for testing of conduction-cooled superconducting solenoid magnets, and was first used to determine the performance of the MICE Coupling Coil. The facility was modified recently to enable testing of solenoid magnets for the Mu2e experiment, which operate at much higher current than the Coupling Coil. One pair of low current conduction-cooled copper and NbTi leads was replaced with two pairs of 10 kA HTS leads cooled by heat exchange with liquid nitrogen and liquid helium. The new design, with additional control and monitoring capability, also providesmore » helium cooling of the superconducting magnet leads by conduction. A high current power supply with energy extraction was added, and several improvements to the quench protection and characterization system were made. Here we present details of these changes and report on performance results from a test of the Mu2e prototype Transport Solenoid (TS) module. Progress on additional improvements in preparation for production TS module testing will be presented.« less

Improvements and Performance of the Fermilab Solenoid Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orris, Darryl; Arnold, Don; Brandt, Jeffrey

Here, the Solenoid Test Facility at Fermilab was built using a large vacuum vessel for testing of conduction-cooled superconducting solenoid magnets, and was first used to determine the performance of the MICE Coupling Coil. The facility was modified recently to enable testing of solenoid magnets for the Mu2e experiment, which operate at much higher current than the Coupling Coil. One pair of low current conduction-cooled copper and NbTi leads was replaced with two pairs of 10 kA HTS leads cooled by heat exchange with liquid nitrogen and liquid helium. The new design, with additional control and monitoring capability, also providesmore » helium cooling of the superconducting magnet leads by conduction. A high current power supply with energy extraction was added, and several improvements to the quench protection and characterization system were made. Here we present details of these changes and report on performance results from a test of the Mu2e prototype Transport Solenoid (TS) module. Progress on additional improvements in preparation for production TS module testing will be presented.« less

Evaluation of a liquid cooling garment as a component of the Launch and Entry Suit (LES)

NASA Technical Reports Server (NTRS)

Waligora, J.; Charles, J.; Fritsch, I.; Fortney, S.; Siconolfi, S.; Pepper, L.; Bagian, L.; Kumar, V.

1994-01-01

The LES is a partial pressure suit and a component of the shuttle life support system used during launch and reentry. The LES relies on gas ventilation with cabin air to provide cooling. There are conditions during nominal launch and reentry, landing, and post-landing phases when cabin temperature is elevated. Under these conditions, gas cooling may result in some discomfort and some decrement in orthostatic tolerance. There are emergency conditions involving loss of cabin ECS capability that would challenge crew thermal tolerance. The results of a series of tests are presented. These tests were conducted to assess the effectiveness of a liquid-cooled garment in alleviating thermal discomfort, orthostatic intolerance, and thermal intolerance during simulated mission phases.

Design and Implementation of a Thermal Load Reduction System for a Hyundai Sonata PHEV for Improved Range

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rugh, John P; Kreutzer, Cory J; Scott, Matthew

Increased adoption of electric-drive vehicles requires overcoming hurdles including limited vehicle range. Vehicle cabin heating and cooling demand for occupant climate control requires energy from the main battery and has been shown to significantly degrade vehicle range. During peak cooling and heating conditions, climate control can require as much as or more energy than propulsion. As part of an ongoing project, the National Renewable Energy Laboratory and project partners Hyundai America Technical Center, Inc., Gentherm, Pittsburgh Glass Works, PPG Industries, Sekisui, 3 M, and Hanon Systems developed a thermal load reduction system to reduce the range penalty associated with electricmore » vehicle climate control. Solar reflective paint, solar control glass, heated and cooled/ventilated seats, heated surfaces, and a heated windshield with door demisters were integrated into a Hyundai Sonata plug-in hybrid electric vehicle. Cold weather field-testing was conducted in Fairbanks, Alaska, and warm weather testing was conducted in Death Valley, California, to assess the system performance in comparison to the baseline production vehicle. In addition, environmental chamber testing at peak heating and cooling conditions was performed to assess the performance of the system in standardized conditions compared to the baseline. Experimental results are presented in this paper, providing quantitative data to automobile manufacturers on the impact of climate control thermal load reduction technologies to increase the advanced thermal technology adoption and market penetration of electric drive vehicles.« less

Performance Evaluation of a Thermal Load Reduction System in a Hyundai Sonata PHEV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kreutzer, Cory J; Rugh, John P; Titov, Eugene V

Increased adoption of electric-drive vehicles (EDVs) requires overcoming hurdles including limited vehicle range. Vehicle cabin heating and cooling demand for occupant climate control requires energy from the main battery and has been shown to significantly degrade vehicle range. During peak cooling and heating conditions, climate control can require as much or more energy as propulsion. As part of an ongoing project, NREL and project partners Hyundai America Technical Center, Inc. (HATCI), Gentherm , Pittsburgh Glass Works (PGW), PPG Industries, Sekisui, 3M, and Hanon Systems developed a thermal load reduction system in order to reduce the range penalty associated with electricmore » vehicle climate control. Solar reflective paint, solar control glass, heated and cooled/ventilated seats, heated surfaces, and heated windshield with door demisters were integrated into a Hyundai Sonata plug-in hybrid electric vehicle (PHEV). Cold weather field-testing was conducted in Fairbanks, Alaska while warm weather testing was conducted in Death Valley, California to assess the system performance in comparison to the baseline production vehicle. In addition, environmental chamber testing at peak heating and cooling conditions was performed to assess the performance of the system in standardized conditions compared to the baseline. Experimental results are presented in this paper providing quantitative data to automobile manufacturers on the impact of climate control thermal load reduction technologies to increase the advanced thermal technology adoption and market penetration of electric drive vehicles.« less

Physiologic Responses Produced by Active and Passive Personal Cooling Vests

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Luna, Bernadette

2000-01-01

Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to document and compare the subjects' response to three cooling vests in their recommended configurations. The Life Enhancement Tech (LET) lightweight active cooling vest with cap, the MicroClimate Systems Change of Phase garment (MCS), and the Steele Vest were each used to cool the chest regions of 12 male and 8 female Healthy subjects (21 to 69 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approx. 22 C), were tested for 60 min. with one of the cooling garments. The LET active garment had an initial coolant fluid inlet temperature of 60 F, and was ramped down to 50 F. Oral, right and left ear canal temperatures were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. For men, all three vests had similar, significant cooling effects. Decreases in the average rectal temperature, oral temperature, and ear canal temperatures were approximately 0.2 C, 0.2 C and 0.1 C, respectively. In contrast to the men, the female subjects wearing the MCS and Steel vests had similar cooling responses in which the core temperature remained elevated and oral and ear canal temperatures did not drop. The LET active garment cooled most of the female subjects in this study; rectal, oral and ear temperature decreased about 0.2 C, 0.3 C and 0.3 C, respectively. These results show that the garment configurations tested do not elicit a similar thermal response in all subjects. A gender difference is evident. The LET active garment configuration was most effective in decreasing temperatures of the female subjects; the MCS vest was least effective. For male subjects, the three vests appear to be more nearly equivalent. The active garment system under study included a cooling cap, which may account for some of the difference in response.

Summary of NASA Lewis Research Center solar heating and cooling and wind energy programs

NASA Technical Reports Server (NTRS)

Vernon, R. W.

1975-01-01

Plans for the construction and operation of a solar heating and cooling system in conjunction with a office building being constructed at Langley Research Center, are discussed. Supporting research and technology includes: testing of solar collectors with a solar simulator, outdoor testing of collectors, property measurements of selective and nonselective coatings for solar collectors, and a solar model-systems test loop. The areas of a wind energy program that are being conducted include: design and operation of a 100-kW experimental wind generator, industry-designed and user-operated wind generators in the range of 50 to 3000 kW, and supporting research and technology for large wind energy systems. An overview of these activities is provided.

Testing of an Integrated Reactor Core Simulator and Power Conversion System with Simulated Reactivity Feedback

NASA Technical Reports Server (NTRS)

Bragg-Sitton, Shannon M.; Hervol, David S.; Godfroy, Thomas J.

2009-01-01

A Direct Drive Gas-Cooled (DDG) reactor core simulator has been coupled to a Brayton Power Conversion Unit (BPCU) for integrated system testing at NASA Glenn Research Center (GRC) in Cleveland, OH. This is a closed-cycle system that incorporates an electrically heated reactor core module, turbo alternator, recuperator, and gas cooler. Nuclear fuel elements in the gas-cooled reactor design are replaced with electric resistance heaters to simulate the heat from nuclear fuel in the corresponding fast spectrum nuclear reactor. The thermodynamic transient behavior of the integrated system was the focus of this test series. In order to better mimic the integrated response of the nuclear-fueled system, a simulated reactivity feedback control loop was implemented. Core power was controlled by a point kinetics model in which the reactivity feedback was based on core temperature measurements; the neutron generation time and the temperature feedback coefficient are provided as model inputs. These dynamic system response tests demonstrate the overall capability of a non-nuclear test facility in assessing system integration issues and characterizing integrated system response times and response characteristics.

Testing of an Integrated Reactor Core Simulator and Power Conversion System with Simulated Reactivity Feedback

NASA Technical Reports Server (NTRS)

Bragg-Sitton, Shannon M.; Hervol, David S.; Godfroy, Thomas J.

2010-01-01

A Direct Drive Gas-Cooled (DDG) reactor core simulator has been coupled to a Brayton Power Conversion Unit (BPCU) for integrated system testing at NASA Glenn Research Center (GRC) in Cleveland, Ohio. This is a closed-cycle system that incorporates an electrically heated reactor core module, turboalternator, recuperator, and gas cooler. Nuclear fuel elements in the gas-cooled reactor design are replaced with electric resistance heaters to simulate the heat from nuclear fuel in the corresponding fast spectrum nuclear reactor. The thermodynamic transient behavior of the integrated system was the focus of this test series. In order to better mimic the integrated response of the nuclear-fueled system, a simulated reactivity feedback control loop was implemented. Core power was controlled by a point kinetics model in which the reactivity feedback was based on core temperature measurements; the neutron generation time and the temperature feedback coefficient are provided as model inputs. These dynamic system response tests demonstrate the overall capability of a non-nuclear test facility in assessing system integration issues and characterizing integrated system response times and response characteristics.

Performance of a 10-kJ SMES model cooled by liquid hydrogen thermo-siphon flow for ASPCS study

NASA Astrophysics Data System (ADS)

Makida, Y.; Shintomi, T.; Hamajima, T.; Ota, N.; Katsura, M.; Ando, K.; Takao, T.; Tsuda, M.; Miyagi, D.; Tsujigami, H.; Fujikawa, S.; Hirose, J.; Iwaki, K.; Komagome, T.

2015-12-01

We propose a new electrical power storage and stabilization system, called an Advanced Superconducting Power Conditioning System (ASPCS), which consists of superconducting magnetic energy storage (SMES) and hydrogen energy storage, converged on a liquid hydrogen station for fuel cell vehicles. A small 10- kJ SMES system, in which a BSCCO coil cooled by liquid hydrogen was installed, was developed to create an experimental model of an ASPCS. The SMES coil is conductively cooled by liquid hydrogen flow through a thermo-siphon line under a liquid hydrogen buffer tank. After fabrication of the system, cooldown tests were carried out using liquid hydrogen. The SMES coil was successfully charged up to a nominal current of 200 A. An eddy current loss, which was mainly induced in pure aluminum plates pasted onto each pancake coils for conduction cooling, was also measured.

A direct-interface fusible heat sink for astronaut cooling

NASA Technical Reports Server (NTRS)

Lomax, Curtis; Webbon, B. W.

1990-01-01

Astronaut cooling during extravehicular activity is a critical design issue in developing a portable life support system that meets the requirements of a space station mission. Some the requirements are that the cooling device can be easily regenerable and nonventing during operation. In response to this, a direct-interface, fusible heat sink prototpye with freezable quick-disconnects was developed. A proof-of-concept prototype was constructed and tested that consists of an elastic container filled with normal tap water and having two quick-disconnects embedded in a wall. These quick-disconnects are designed so that they may be frozen with the ice and yet still be joined to the cooling system, allowing an immediate flow path. The inherent difficulties in a direct-interface heat sink have been overcome, i.e., (1) establishing an initial flow path; (2) avoiding low-flow freeze-up; and (3) achieving adequate heat-transfer rates at the end of the melting process. The requirements, design, fabrication, and testing are discussed.

A direct-interface, fusible heat sink for astronaut cooling

NASA Technical Reports Server (NTRS)

Lomax, Curtis; Webbon, B. W.

1990-01-01

Astronaut cooling during extravehicular activity is a critical design issue in developing a portable life support system that meets the requirements of a space station mission. Some of the requirements are that the cooling device can be easily regenerable and nonventing during operation. In response to this, a direct-interface, fusible heat sink prototype with freezable quick-disconnects was developed. A proof-of-concept prototype was constructed and tested that consists of an elastic container filled with normal tap water and having two quick-disconnects embedded in a wall. These quick-disconnects are designed so that they may be frozen with the ice and yet still be joined to the cooling system, allowing an immediate flow path. The inherent difficulties in a direct-interface heat sink have been overcome, i.e., (1) establishing an initial flow path; (2) avoiding low-flow freeze-up; and (3) achieving adequate heat-transfer rates at the end of the melting process. The requirements, design, fabrication, and testing are discussed.

High-fidelity cryothermal test of a subscale large space telescope

NASA Astrophysics Data System (ADS)

DiPirro, M.; Tuttle, J.; Ollendorf, S.; Mattern, A.; Leisawitz, D.; Jackson, M.; Francis, J.; Hait, T.; Cleveland, P.; Muheim, D.; Mastropietro, A. J.

2007-09-01

To take advantage of the unique environment of space and optimize infrared observations for faint sources, space telescopes must be cooled to low temperatures. The new paradigm in cooling large space telescopes is to use a combination of passive radiative cooling and mechanical cryocoolers. The passive system must shield the telescope from the Sun, Earth, and the warm spacecraft components while providing radiative cooling to deep space. This shield system is larger than the telescope itself, and must attenuate the incoming energy by over one million to limit heat input to the telescope. Testing of such a system on the ground is a daunting task due to the size of the thermal/vacuum chamber required and the degree of thermal isolation necessary between the room temperature and cryogenic parts of the shield. These problems have been attacked in two ways: by designing a subscale version of a larger sunshield and by carefully closing out radiation sneak paths. The 18% scale (the largest diameter shield was 1.5 m) version of the SPIRIT Origins Probe telescope shield was tested in a low cost helium shroud within a 3.1 m diameter x 4.6 m long LN II shrouded vacuum chamber. Thermal straps connected from three shield stages to the liquid helium cooled shroud were instrumented with heaters and thermometers to simulate mechanical cryocooler stages at 6 K, 18-20 K, and 45-51 K. Performance data showed that less than 10 microwatts of radiative heat leaked from the warm to cold sides of the shields during the test. The excellent agreement between the data and the thermal models is discussed along with shroud construction techniques.

Design, fabrication, testing, and delivery of a solar energy collector system for residential heating and cooling

NASA Technical Reports Server (NTRS)

Holland, T. H.; Borzoni, J. T.

1976-01-01

A low cost flat plate solar energy collector was designed for the heating and cooling of residential buildings. The system meets specified performance requirements, at the desired system operating levels, for a useful life of 15 to 20 years, at minimum cost and uses state-of-the-art materials and technology. The rationale for the design method was based on identifying possible material candidates for various collector components and then selecting the components which best meet the solar collector design requirements. The criteria used to eliminate certain materials were: performance and durability test results, cost analysis, and prior solar collector fabrication experience.

Temperature Controller System for Gas Gun Targets

NASA Astrophysics Data System (ADS)

Bucholtz, Scott; Sheffield, Stephen

2005-07-01

A temperature controller system capable of heating and cooling gas gun targets over the range -75 C to +200 C was designed and tested. The system uses cold nitrogen gas from a liquid nitrogen Dewar for cooling and compressed air for heating. Two gas flow heaters control the gas temperature for both heating and cooling. One heater controls the temperature of the target mounting plate and the other the temperature of a copper tubing coil surrounding the target. Each heater is separately adjustable, so the target material will achieve a uniform temperature throughout its volume. A magnetic gauge with integrated thermocouples was developed to measure the internal temperature of the target. Using this system shock experiments, including equation-of-state measurements and shock initiation of high explosives, can be performed over a range of initial temperatures. Successful tests were completed on Teflon samples. This work was supported by the NNSA Enhanced Surveillance Campaign through contract DE-ACO4-01AL66850.

Liquid-cooled clothing for hot mine rescue work

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-04-01

To prevent exhaustion caused by thermal stress, a rescuer can wear a liquid-cooled hood and vest which absorbs heat, thereby reducing the heat-induced strain on the rescuer's heart and circulatory system. Liquid coolant is continuously circulated through a self-contained system in which the coolant is chilled by a heat sink on the wearer's belt. Cooling duration is approximately 40 minutes when both the hood and vest are worn. Tests were conducted at NASA's Ames Research Center to evaluate the effectiveness of this system. When using the hood and vest with a refrigerated water supply, thermal strain on the wearer wasmore » cut in half and the heart rate was reduced by 30 to 50 beats per minute. Body temperature was significantly lowered, about 0.65/sup 0/C. This system can increase safety for rescue workers who must work in a hot environment, especially when they are not acclimated to high temperaures. Laboratory tests also were conducted using members of a mine rescue team.« less

An Hybrid liquid nitrogen system to cool a large detector

NASA Astrophysics Data System (ADS)

l'Allemand, J. L. Lizon a.

2017-12-01

OmegaCAM is a wide field camera housing a mosaic of 32 CCD detectors. For the optimal trade-off between dark current, sensitivity, and cosmetics, these detectors need to be operated at a temperature of about 155 K. The detectors mosaic with a total area of 630 cm2 directly facing the Dewar entrance window, is exposed to a considerable radiation heat load. This can only be achieved with a high-performing cooling system. In addition this system has to be operated at the moving focal plane of a telescope. The paper describes the cooling system, which is build such that it makes the most efficient use of the cooling power of the liquid nitrogen. This is obtained by forcing the nitrogen through a series of well designed and strategically distributed heat exchangers. Results and performance of the system recorded during the laboratory system testing are reported as well. In addition to the cryogenic performance, the document reports also about the overall performance of the instrument including long term vacuum behavior.

System Testing of Ground Cooling System Components

NASA Technical Reports Server (NTRS)

Ensey, Tyler Steven

2014-01-01

This internship focused primarily upon software unit testing of Ground Cooling System (GCS) components, one of the three types of tests (unit, integrated, and COTS/regression) utilized in software verification. Unit tests are used to test the software of necessary components before it is implemented into the hardware. A unit test determines that the control data, usage procedures, and operating procedures of a particular component are tested to determine if the program is fit for use. Three different files are used to make and complete an efficient unit test. These files include the following: Model Test file (.mdl), Simulink SystemTest (.test), and autotest (.m). The Model Test file includes the component that is being tested with the appropriate Discrete Physical Interface (DPI) for testing. The Simulink SystemTest is a program used to test all of the requirements of the component. The autotest tests that the component passes Model Advisor and System Testing, and puts the results into proper files. Once unit testing is completed on the GCS components they can then be implemented into the GCS Schematic and the software of the GCS model as a whole can be tested using integrated testing. Unit testing is a critical part of software verification; it allows for the testing of more basic components before a model of higher fidelity is tested, making the process of testing flow in an orderly manner.

Operational Characteristics of Two Commercially Available Personal Cooling Vests

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Webbon, Bruce W.; Luna, Bernadette (Technical Monitor)

1996-01-01

Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to compare the effectiveness of two passive cooling vests, and to measure the body temperature and circulatory changes produced by each cooling vest configuration. A Life Enhancement Technologies, (LET) ice vest garment and a Steele, Inc. vest were used to cool the chest region of 11 male subjects (25 to 55 yr) in this study. Calf, forearm and finger blood flows were measured using a tetrapolar impedance rheograph. The subjects, seated in an upright position at normal room temperature (approximately 21 C) were tested for 60 min. with the cooling system operating at its maximum cooling capacity. Blood flows were recorded continuously using a computer data acquisition system with a sampling frequency of 250 Hz. Oral, right and left ear temperatures and cooling system parameters were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; respiration; and an activity index were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. No significant differences were found in either the oral or ear temperature responses to the two vests. However, the rectal and mean skin temperatures at the end of the cooling period were both significantly lower (P less than 0.05), approximately 0.2 and 1.9 C, respectively for the LET vest than for the Steele garment. These data show that different vest configurations may produce different thermal responses in healthy male subjects which should be considered in the use of these cooling garments.

Development of Passive Fuel Cell Thermal Management Heat Exchanger

NASA Technical Reports Server (NTRS)

Burke, Kenneth A.; Jakupca, Ian J.; Colozza, Anthony J.

2010-01-01

The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates that could conduct the heat, provide a sufficiently uniform temperature heat sink for each cell of the fuel cell stack, and be substantially lighter than the conventional thermal management approach. Tests were run with different materials to evaluate the design approach to a heat exchanger that could interface with the edges of the passive cooling plates. Measurements were made during fuel cell operation to determine the temperature of individual cooling plates and also to determine the temperature uniformity from one cooling plate to another.

Thermal Performance Testing of EMU and CSAFE Liquid Cooling Gannents

NASA Technical Reports Server (NTRS)

Rhodes, Richard; Bue, Grant; Meginnis, Ian; Hakam, Mary; Radford, Tamara

2013-01-01

Future exploration missions require the development of a new liquid cooling garment (LCG) to support the next generation extravehicular activity (EVA) suit system. The new LCG must offer greater system reliability, optimal thermal performance as required by mission directive, and meet other design requirements including improved tactile comfort. To advance the development of a future LCG, a thermal performance test was conducted to evaluate: (1) the comparable thermal performance of the EMU LCG and the CSAFE developed engineering evaluation unit (EEU) LCG, (2) the effect of the thermal comfort undergarment (TCU) on the EMU LCG tactile and thermal comfort, and (3) the performance of a torso or upper body only LCG shirt to evaluate a proposed auxiliary loop. To evaluate the thermal performance of each configuration, a metabolic test was conducted using the Demonstrator Spacesuit to create a relevant test environment. Three (3) male test subjects of similar height and weight walked on a treadmill at various speeds to produce three different metabolic loads - resting (300-600 BTU/hr), walking at a slow pace (1200 BTU/hr), and walking at a brisk pace (2200 BTU/hr). Each subject participated in five tests - two wearing the CSAFE full LCG, one wearing the EMU LCG without TCUs, one wearing the EMU LCG with TCUs, and one with the CSAFE shirt-only. During the test, performance data for the breathing air and cooling water systems and subject specific data was collected to define the thermal performance of the configurations. The test results show that the CSAFE EEU LCG and EMU LCG with TCU had comparable performance. The testing also showed that an auxiliary loop LCG, sized similarly to the shirt-only configuration, should provide adequate cooling for contingency scenarios. Finally, the testing showed that the TCU did not significantly hinder LCG heat transfer, and may prove to be acceptable for future suit use with additional analysis and testing.

Simulation of an active cooling system for photovoltaic modules

NASA Astrophysics Data System (ADS)

Abdelhakim, Lotfi

2016-06-01

Photovoltaic cells are devices that convert solar radiation directly into electricity. However, solar radiation increases the photovoltaic cells temperature [1] [2]. The temperature has an influence on the degradation of the cell efficiency and the lifetime of a PV cell. This work reports on a water cooling technique for photovoltaic panel, whereby the cooling system was placed at the front surface of the cells to dissipate excess heat away and to block unwanted radiation. By using water as a cooling medium for the photovoltaic solar cells, the overheating of closed panel is greatly reduced without prejudicing luminosity. The water also acts as a filter to remove a portion of solar spectrum in the infrared band but allows transmission of the visible spectrum most useful for the PV operation. To improve the cooling system efficiency and electrical efficiency, uniform flow rate among the cooling system is required to ensure uniform distribution of the operating temperature of the PV cells. The aims of this study are to develop a 3D thermal model to simulate the cooling and heat transfer in Photovoltaic panel and to recommend a cooling technique for the PV panel. The velocity, pressure and temperature distribution of the three-dimensional flow across the cooling block were determined using the commercial package, Fluent. The second objective of this work is to study the influence of the geometrical dimensions of the panel, water mass flow rate and water inlet temperature on the flow distribution and the solar panel temperature. The results obtained by the model are compared with experimental results from testing the prototype of the cooling device.

Optimized Heat Pipe Backup Cooling System Tested with a Stirling Convertor

NASA Technical Reports Server (NTRS)

Schwendeman, Carl L.; Tarau, Calin; Schifer, Nicholas A.; Anderson, William G.; Garner, Scott

2016-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal variable conductance heat pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor by bypassing the heat during stops. In a previous NASA Small Business Innovation Research (SBIR) Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for the Stirling RPS. In 2012, one of these VCHPs was successfully tested at NASA Glenn Research Center with a Stirling convertor as an Advanced Stirling Radioisotope Generator (ASRG) backup cooling system. The prototype; however, was not optimized and did not reflect the final heat rejection path. ACT through further funding has developed a semioptimized prototype with the finalized heat path for testing at Glenn with a Stirling convertor. The semioptimized system features a two-phase radiator and is significantly smaller and lighter than the prior prototype to reflect a higher level of flight readiness. The VCHP is designed to activate and remove heat from the GPHS during stoppage with a small temperature increase from the nominal vapor temperature. This small temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the multilayer insulation (MLI). The VCHP passively allows the Stirling convertor to be turned off multiple times during a mission with potentially unlimited off durations. Having the ability to turn the Stirling off allows for the Stirling to be reset and reduces vibrations on the platform during sensitive measurements or procedures. This paper presents the design of the VCHP and its test results with a Stirling convertor at Glenn. Tests were carried for multiple on and off cycles to demonstrate repeatability. The impacts associated with the addition of the VCHP to the system are also addressed in terms of mass and additional heat losses due to the presence of the VCHP.

Building Modelling Methodologies for Virtual District Heating and Cooling Networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saurav, Kumar; Choudhury, Anamitra R.; Chandan, Vikas

District heating and cooling systems (DHC) are a proven energy solution that has been deployed for many years in a growing number of urban areas worldwide. They comprise a variety of technologies that seek to develop synergies between the production and supply of heat, cooling, domestic hot water and electricity. Although the benefits of DHC systems are significant and have been widely acclaimed, yet the full potential of modern DHC systems remains largely untapped. There are several opportunities for development of energy efficient DHC systems, which will enable the effective exploitation of alternative renewable resources, waste heat recovery, etc., inmore » order to increase the overall efficiency and facilitate the transition towards the next generation of DHC systems. This motivated the need for modelling these complex systems. Large-scale modelling of DHC-networks is challenging, as it has several components interacting with each other. In this paper we present two building methodologies to model the consumer buildings. These models will be further integrated with network model and the control system layer to create a virtual test bed for the entire DHC system. The model is validated using data collected from a real life DHC system located at Lulea, a city on the coast of northern Sweden. The test bed will be then used for simulating various test cases such as peak energy reduction, overall demand reduction etc.« less

Thermal Comfort and Sensation in Men Wearing a Cooling System Controlled by Skin Temperature

DTIC Science & Technology

2007-07-01

The study was done to determine whether thermal comfort (TC), thermal sensation (TS), and subjective factors gauging environmental stress were...improvement in thermal comfort . Methods: Eight male volunteers exercised at moderate work intensity (425 W) in three microclimate cooling tests. The

Application of additive laser technologies in the gas turbine blades design process

NASA Astrophysics Data System (ADS)

Shevchenko, I. V.; Rogalev, A. N.; Osipov, S. K.; Bychkov, N. M.; Komarov, I. I.

2017-11-01

An emergence of modern innovative technologies requires delivering new and modernization existing design and production processes. It is especially relevant for designing the high-temperature turbines of gas turbine engines, development of which is characterized by a transition to higher parameters of working medium in order to improve their efficient performance. A design technique for gas turbine blades based on predictive verification of thermal and hydraulic models of their cooling systems by testing of a blade prototype fabricated using the selective laser melting technology was presented in this article. Technique was proven at the time of development of the first stage blade cooling system for the high-pressure turbine. An experimental procedure for verification of a thermal model of the blades with convective cooling systems based on the comparison of heat-flux density obtained from the numerical simulation data and results of tests in a liquid-metal thermostat was developed. The techniques makes it possible to obtain an experimentally tested blade version and to exclude its experimental adjustment after the start of mass production.

Temperature measurement using infrared imaging systems during turbine engine altitude testing

NASA Technical Reports Server (NTRS)

Burns, Maureen E.

1994-01-01

This report details the use of infrared imaging for temperature measurement and thermal pattern determination during simulated altitude engine testing in the NASA Lewis Propulsion Systems Laboratory. Three identical argon-cooled imaging systems were installed in the facility exhaust collector behind sapphire windows to look at engine internal surfaces. The report describes the components of each system, presents the specifics of the complicated installation, and explains the operation of the systems during engine testing. During the program, several problems emerged, such as argon contamination system, component overheating, cracked sapphire windows, and other unexplained effects. This report includes a summary of the difficulties as well as the solutions developed. The systems performed well, considering they were in an unusually harsh exhaust environment. Both video and digital data were recorded, and the information provided valuable material for the engineers and designers to quickly make any necessary design changes to the engine hardware cooling system. The knowledge and experience gained during this program greatly simplified the installation and use of the systems during later test programs in the facility. The infrared imaging systems have significantly enhanced the measurement capabilities of the facility, and have become an outstanding and versatile testing resource in the Propulsion Systems Laboratory.

Experimental determination of drift and PM10 cooling tower emissions: Influence of components and operating conditions.

PubMed

Ruiz, J; Kaiser, A S; Lucas, M

2017-11-01

Cooling tower emissions have become an increasingly common hazard to the environment (air polluting, ice formation and salts deposition) and to the health (Legionella disease) in the last decades. Several environmental policies have emerged in recent years limiting cooling tower emissions but they have not prevented an increasing intensity of outbreaks. Since the level of emissions depends mainly on cooling tower component design and the operating conditions, this paper deals with an experimental investigation of the amount of emissions, drift and PM 10 , emitted by a cooling tower with different configurations (drift eliminators and distribution systems) and working under several operating conditions. This objective is met by the measurement of cooling tower source emission parameters by means of the sensitive paper technique. Secondary objectives were to contextualize the observed emission rates according to international regulations. Our measurements showed that the drift rates included in the relevant international standards are significantly higher than the obtained results (an average of 100 times higher) and hence, the environmental problems may occur. Therefore, a revision of the standards is recommended with the aim of reducing the environmental and human health impact. By changing the operating conditions and the distribution system, emissions can be reduced by 52.03% and 82% on average. In the case of drift eliminators, the difference ranges from 18.18% to 98.43% on average. As the emissions level is clearly influenced by operating conditions and components, regulation tests should be referred to default conditions. Finally, guidelines to perform emission tests and a selection criterion of components and conditions for the tested cooling tower are proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Si/Glass Bulk-Micromachined Cryogenic Heat Exchanger for High Heat Loads: Fabrication, Test, and Application Results

PubMed Central

Zhu, Weibin; White, Michael J.; Nellis, Gregory F.; Klein, Sanford A.; Gianchandani, Yogesh B.

2010-01-01

This paper reports on a micromachined Si/glass stack recuperative heat exchanger with in situ temperature sensors. Numerous high-conductivity silicon plates with integrated platinum resistance temperature detectors (Pt RTDs) are stacked, alternating with low-conductivity Pyrex spacers. The device has a 1 × 1-cm2 footprint and a length of up to 3.5 cm. It is intended for use in Joule–Thomson (J–T) coolers and can sustain pressure exceeding 1 MPa. Tests at cold-end inlet temperatures of 237 K–252 K show that the heat exchanger effectiveness is 0.9 with 0.039-g/s helium mass flow rate. The integrated Pt RTDs present a linear response of 0.26%–0.30%/K over an operational range of 205 K–296 K but remain usable at lower temperatures. In self-cooling tests with ethane as the working fluid, a J–T system with the heat exchanger drops 76.1 K below the inlet temperature, achieving 218.7 K for a pressure of 835.8 kPa. The system reaches 200 K in transient state; further cooling is limited by impurities that freeze within the flow stream. In J–T self-cooling tests with an external heat load, the system reaches 239 K while providing 1 W of cooling. In all cases, there is an additional parasitic heat load estimated at 300–500 mW. PMID:20490284

Active cooling from the sixties to NASP

NASA Technical Reports Server (NTRS)

Kelly, H. Neale; Blosser, Max L.

1992-01-01

Vehicles, such as the X-15 or National Aero-Space Plane, traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of this paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years--from early engine structures, which were intended to be tested on the X-15, to structural--are described. Many of the lessons learned from these research efforts are presented.

CPV cells cooling system based on submerged jet impingement: CFD modeling and experimental validation

NASA Astrophysics Data System (ADS)

Montorfano, Davide; Gaetano, Antonio; Barbato, Maurizio C.; Ambrosetti, Gianluca; Pedretti, Andrea

2014-09-01

Concentrating photovoltaic (CPV) cells offer higher efficiencies with regard to the PV ones and allow to strongly reduce the overall solar cell area. However, to operate correctly and exploit their advantages, their temperature has to be kept low and as uniform as possible and the cooling circuit pressure drops need to be limited. In this work an impingement water jet cooling system specifically designed for an industrial HCPV receiver is studied. Through the literature and by means of accurate computational fluid dynamics (CFD) simulations, the nozzle to plate distance, the number of jets and the nozzle pitch, i.e. the distance between adjacent jets, were optimized. Afterwards, extensive experimental tests were performed to validate pressure drops and cooling power simulation results.

Credit BG. View looking northeast down from the tower onto ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit BG. View looking northeast down from the tower onto the two horizontal test stations at Test Stand "D." Station Dy is at the far left (Dy vacuum cell out of view), with in-line exhaust gas cooling sections and steam-driven "air ejector" (or evacuator) discharging engine exhausts to the east. The Dd cell is visible at the lower left, and the Dd exhaust train has the same functions as at Dy. The spherical tank is an electrically heated "accumulator" which supplies steam to the ejectors at Dv, Dd, and Dy stations. Other large piping delivered cooling water to the horizontal train cooling sections. The horizontal duct at the "Y" branch in the Dd train connects the Dd ejector to the Dv and Cv vacuum duct system (a blank can be bolted into this duct to isolate the Dd system). The shed roof for the Dpond test station appears at bottom center of this image. The open steel frame to the lower left of the image supports a hoist and crane for installing or removing test engines from the Dd test cell - Jet Propulsion Laboratory Edwards Facility, Test Stand D, Edwards Air Force Base, Boron, Kern County, CA

Feasibility study of parallel conduction cooling of NbTi magnet and sample probe in a cryogen-free magnet system

NASA Astrophysics Data System (ADS)

Catarino, I.; Soni, V.; Barreto, J.; Martins, D.; Kar, S.

2017-02-01

The conduction cooling of both a 6 T superconducting magnet along with a sample probe in a parallel configuration is addressed in this work. A Gifford-McMahon (GM) cryocooler is directly cooling the NbTi magnet, which aims to be kept at 4 K, while a gas-gap heat switch (GGHS) manages the cooling power to be diverted to the sample probe, which may be swept from 4 K up to 300 K. A first prototype of a GGHS was customized and validated for this purpose. A sample probe assembly has been designed and assembled with the existing cryogen-free magnet system. The whole test setup and components are described and the preliminary experimental results on the integration are presented and discussed. The magnet was charged up to 3 T with a 4 K sample space and up to 1 T with a sweeping sample space temperature up to 300 K while acting on the GGHS. Despite some identified thermal insulation problems that occurred during this first test, the overall results demonstrated the feasibility of the cryogen-free parallel conduction cooling on study.

Progress of a room temperature electron cyclotron resonance ion source using evaporative cooling technology at Institute of Modern Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, W., E-mail: luwang@impcas.ac.cn; University of Chinese Academy of Sciences, Beijing 100049; Xiong, B.

2014-02-15

A new room temperature ECR ion source, Lanzhou Electron Cyclotron Resonance ion source No. 4 (LECR4, previously named DRAGON), is under intense construction at Institute of Modern Physics. LECR4 is designed to operate with 18 GHz microwave frequency. The maximum axial magnetic fields are 2.3 T at injection and 1.3 T at extraction, and the radial field at the plasma chamber wall of 76 mm inner diameter is 1.0–1.2 T. One of the unique features for LECR4 is that its axial solenoids are winded with solid square copper wires which are immersed in a kind of special evaporative cooling mediummore » for cooling purpose. Till now, a prototype of the cooling system has been successfully constructed and tested, which has demonstrated that the cooling efficiency of the designed system could meet the requirements of LECR4 under the routine operation conditions. All the main components of the ion source have been completed. Assembly and commissioning is ongoing. The latest developments and test results will be presented in this paper.« less

Design and Control of Hydronic Radiant Cooling Systems

NASA Astrophysics Data System (ADS)

Feng, Jingjuan

Improving energy efficiency in the Heating Ventilation and Air conditioning (HVAC) systems in buildings is critical to achieve the energy reduction in the building sector, which consumes 41% of all primary energy produced in the United States, and was responsible for nearly half of U.S. CO2 emissions. Based on a report by the New Building Institute (NBI), when HVAC systems are used, about half of the zero net energy (ZNE) buildings report using a radiant cooling/heating system, often in conjunction with ground source heat pumps. Radiant systems differ from air systems in the main heat transfer mechanism used to remove heat from a space, and in their control characteristics when responding to changes in control signals and room thermal conditions. This dissertation investigates three related design and control topics: cooling load calculations, cooling capacity estimation, and control for the heavyweight radiant systems. These three issues are fundamental to the development of accurate design/modeling tools, relevant performance testing methods, and ultimately the realization of the potential energy benefits of radiant systems. Cooling load calculations are a crucial step in designing any HVAC system. In the current standards, cooling load is defined and calculated independent of HVAC system type. In this dissertation, I present research evidence that sensible zone cooling loads for radiant systems are different from cooling loads for traditional air systems. Energy simulations, in EnergyPlus, and laboratory experiments were conducted to investigate the heat transfer dynamics in spaces conditioned by radiant and air systems. The results show that the magnitude of the cooling load difference between the two systems ranges from 7-85%, and radiant systems remove heat faster than air systems. For the experimental tested conditions, 75-82% of total heat gain was removed by radiant system during the period when the heater (simulating the heat gain) was on, while for air system, 61-63% were removed. From a heat transfer perspective, the differences are mainly because the chilled surfaces directly remove part of the radiant heat gains from a zone, thereby bypassing the time-delay effect caused by the interaction of radiant heat gain with non-active thermal mass in air systems. The major conclusions based on these findings are: 1) there are important limitations in the definition of cooling load for a mixing air system described in Chapter 18 of ASHRAE Handbook of Fundamentals when applied to radiant systems; 2) due to the obvious mismatch between how radiant heat transfer is handled in traditional cooling load calculation methods compared to its central role in radiant cooling systems, this dissertation provides improvements for the current cooling load calculation method based on the Heat Balance procedure. The Radiant Time Series method is not appropriate for radiant system applications. The findings also directly apply to the selection of space heat transfer modeling algorithms that are part of all energy modeling software. Cooling capacity estimation is another critical step in a design project. The above mentioned findings and a review of the existing methods indicates that current radiant system cooling capacity estimation methods fail to take into account incident shortwave radiation generated by solar and lighting in the calculation process. This causes a significant underestimation (up to 150% for some instances) of floor cooling capacity when solar load is dominant. Building performance simulations were conducted to verify this hypothesis and quantify the impacts of solar for different design scenarios. A new simplified method was proposed to improve the predictability of the method described in ISO 11855 when solar radiation is present. The dissertation also compares the energy and comfort benefits of the model-based predictive control (MPC) method with a fine-tuned heuristic control method when applied to a heavyweight embedded surface system. A first order dynamic model of a radiant slab system was developed for implementation in model predictive controllers. A calibrated EnergyPlus model of a typical office building in California was used as a testbed for the comparison. The results indicated that MPC is able to reduce the cooling tower energy consumption by 55% and pumping power consumption by 26%, while maintaining equivalent or even better thermal comfort conditions. In summary, the dissertation work has: (1) provided clear evidence that the fundamental heat transfer mechanisms differ between radiant and air systems. These findings have important implications for the development of accurate and reliable design and energy simulation tools; (2) developed practical design methods and guidance to aid practicing engineers who are designing radiant systems; and (3) outlined future research and design tools need to advance the state-of-knowledge and design and operating guidelines for radiant systems.

Cooling During Exercise: An Overlooked Strategy for Enhancing Endurance Performance in the Heat.

PubMed

Stevens, Christopher J; Taylor, Lee; Dascombe, Ben J

2017-05-01

It is well established that endurance performance is negatively affected by environmental heat stress due to a complex interaction of physical, physiological and psychological alterations. Numerous scientific investigations have attempted to improve performance in the heat with pre-cooling (cooling prior to an exercise test), and as such this has become a well-established ergogenic practice for endurance athletes. However, the use of mid-cooling (cooling during an exercise test) has received considerably less research attention in comparison, despite recent evidence to suggest that the advantage gained from mid-cooling may outweigh that of pre-cooling. A range of mid-cooling strategies are beneficial for endurance performance in the heat, including the ingestion of cold fluids and ice slurry, both with and without menthol, as well as cooling of the neck and face region via a cooling collar or water poured on the head and face. The combination of pre-cooling and mid-cooling has also been effective, but few comparisons exist between the timing and type of such interventions. Therefore, athletes should experiment with a range of suitable mid-cooling strategies for their event during mock competition scenarios, with the aim to determine their individual tolerable limits and performance benefits. Based on current evidence, the effect of mid-cooling on core temperature appears largely irrelevant to any subsequent performance improvements, while cardiovascular, skin temperature, central nervous system function and psychophysiological factors are likely involved. Research is lacking on elite athletes, and as such it is currently unclear how this population may benefit from mid-cooling.

Prediction of thermal behaviors of an air-cooled lithium-ion battery system for hybrid electric vehicles

NASA Astrophysics Data System (ADS)

Choi, Yong Seok; Kang, Dal Mo

2014-12-01

Thermal management has been one of the major issues in developing a lithium-ion (Li-ion) hybrid electric vehicle (HEV) battery system since the Li-ion battery is vulnerable to excessive heat load under abnormal or severe operational conditions. In this work, in order to design a suitable thermal management system, a simple modeling methodology describing thermal behavior of an air-cooled Li-ion battery system was proposed from vehicle components designer's point of view. A proposed mathematical model was constructed based on the battery's electrical and mechanical properties. Also, validation test results for the Li-ion battery system were presented. A pulse current duty and an adjusted US06 current cycle for a two-mode HEV system were used to validate the accuracy of the model prediction. Results showed that the present model can give good estimations for simulating convective heat transfer cooling during battery operation. The developed thermal model is useful in structuring the flow system and determining the appropriate cooling capacity for a specified design prerequisite of the battery system.

77 FR 38857 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-29

... Treatment, Heating Ventilation and Air Conditioning Systems.'' This new standard provides comprehensive test... Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled... NUCLEAR REGULATORY COMMISSION [NRC-2012-0152] Design, Inspection, and Testing Criteria for Air...

Monitoring of biofilm-associated Legionella pneumophila on different substrata in model cooling tower system.

PubMed

Türetgen, Irfan; Cotuk, Aysin

2007-02-01

Cooling towers have the potential to develop infectious concentrations of Legionella pneumophila. Legionella counts increases where biofilm and warm water temperatures are present. In this study, biofilm associated L. pneumophila and heterotrophic bacteria were compared in terms of material dependence. Model cooling tower system was experimentally infected by L. pneumophila standard strain and monthly monitored. Different materials were tested for a period of 180 days. The lowest L. pneumophila and heterotrophic plate counts were measured on plastic polymers, whereas L. pneumophila and heterotrophic bacteria were accumulated rapidly on galvanized steel surfaces. It can be concluded that selection of plastic polymers, as a manufacturing material, are suitable for recirculating water systems.

KSC-02pd0027

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility look over the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. NICMOS is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

KSC-02pd0028

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- A closeup view of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. NICMOS II is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

Evaluation of water cooled supersonic temperature and pressure probes for application to 2000 F flows

NASA Technical Reports Server (NTRS)

Lagen, Nicholas T.; Seiner, John M.

1990-01-01

The development of water cooled supersonic probes used to study high temperature jet plumes is addressed. These probes are: total pressure, static pressure, and total temperature. The motivation for these experiments is the determination of high temperature supersonic jet mean flow properties. A 3.54 inch exit diameter water cooled nozzle was used in the tests. It is designed for exit Mach 2 at 2000 F exit total temperature. Tests were conducted using water cooled probes capable of operating in Mach 2 flow, up to 2000 F total temperature. Of the two designs tested, an annular cooling method was chosen as superior. Data at the jet exit planes, and along the jet centerline, were obtained for total temperatures of 900 F, 1500 F, and 2000 F, for each of the probes. The data obtained from the total and static pressure probes are consistent with prior low temperature results. However, the data obtained from the total temperature probe was affected by the water coolant. The total temperature probe was tested up to 2000 F with, and without, the cooling system turned on to better understand the heat transfer process at the thermocouple bead. The rate of heat transfer across the thermocouple bead was greater when the coolant was turned on than when the coolant was turned off. This accounted for the lower temperature measurement by the cooled probe. The velocity and Mach number at the exit plane and centerline locations were determined from the Rayleigh-Pitot tube formula.

Muon Accelerator Program (MAP) | Neutrino Factory | Research Goals

Science.gov Websites

; Committees Research Goals Research & Development Design & Simulation Technology Development Systems Demonstrations Activities MASS Muon Cooling MuCool Test Area MICE Experiment MERIT Muon Collider Research Goals Why Muons at the Energy Frontier? How does it work? Graphics Animation Neutrino Factory Research Goals

A magnetic resonance (MR) microscopy system using a microfluidically cryo-cooled planar coil.

PubMed

Koo, Chiwan; Godley, Richard F; Park, Jaewon; McDougall, Mary P; Wright, Steven M; Han, Arum

2011-07-07

We present the development of a microfluidically cryo-cooled planar coil for magnetic resonance (MR) microscopy. Cryogenically cooling radiofrequency (RF) coils for magnetic resonance imaging (MRI) can improve the signal to noise ratio (SNR) of the experiment. Conventional cryostats typically use a vacuum gap to keep samples to be imaged, especially biological samples, at or near room temperature during cryo-cooling. This limits how close a cryo-cooled coil can be placed to the sample. At the same time, a small coil-to-sample distance significantly improves the MR imaging capability due to the limited imaging depth of planar MR microcoils. These two conflicting requirements pose challenges to the use of cryo-cooling in MR microcoils. The use of a microfluidic based cryostat for localized cryo-cooling of MR microcoils is a step towards eliminating these constraints. The system presented here consists of planar receive-only coils with integrated cryo-cooling microfluidic channels underneath, and an imaging surface on top of the planar coils separated by a thin nitrogen gas gap. Polymer microfluidic channel structures fabricated through soft lithography processes were used to flow liquid nitrogen under the coils in order to cryo-cool the planar coils to liquid nitrogen temperature (-196 °C). Two unique features of the cryo-cooling system minimize the distance between the coil and the sample: (1) the small dimension of the polymer microfluidic channel enables localized cooling of the planar coils, while minimizing thermal effects on the nearby imaging surface. (2) The imaging surface is separated from the cryo-cooled planar coil by a thin gap through which nitrogen gas flows to thermally insulate the imaging surface, keeping it above 0 °C and preventing potential damage to biological samples. The localized cooling effect was validated by simulations, bench testing, and MR imaging experiments. Using this cryo-cooled planar coil system inside a 4.7 Tesla MR system resulted in an average image SNR enhancement of 1.47 ± 0.11 times relative to similar room-temperature coils. This journal is © The Royal Society of Chemistry 2011

A Magnetic Resonance (MR) Microscopy System using a Microfluidically Cryo-Cooled Planar Coil

PubMed Central

Koo, Chiwan; Godley, Richard F.; Park, Jaewon; McDougall, Mary P.; Wright, Steven M.; Han, Arum

2011-01-01

We present the development of a microfluidically cryo-cooled planar coil for magnetic resonance (MR) microscopy. Cryogenically cooling radiofrequency (RF) coils for magnetic resonance imaging (MRI) can improve the signal to noise ratio (SNR) of the experiment. Conventional cryostats typically use a vacuum gap to keep samples to be imaged, especially biological samples, at or near room temperature during cryo-cooling. This limits how close a cryo-cooled coil can be placed to the sample. At the same time, a small coil-to-sample distance significantly improves the MR imaging capability due to the limited imaging depth of planar MR microcoils. These two conflicting requirements pose challenges to the use of cryo-cooling in MR microcoils. The use of a microfluidic based cryostat for localized cryo-cooling of MR microcoils is a step towards eliminating these constraints. The system presented here consists of planar receive-only coils with integrated cryo-cooling microfluidic channels underneath, and an imaging surface on top of the planar coils separated by a thin nitrogen gas gap. Polymer microfluidic channel structures fabricated through soft lithography processes were used to flow liquid nitrogen under the coils in order to cryo-cool the planar coils to liquid nitrogen temperature (−196°C). Two unique features of the cryo-cooling system minimize the distance between the coil and the sample: 1) The small dimension of the polymer microfluidic channel enables localized cooling of the planar coils, while minimizing thermal effects on the nearby imaging surface. 2) The imaging surface is separated from the cryo-cooled planar coil by a thin gap through which nitrogen gas flows to thermally insulate the imaging surface, keeping it above 0°C and preventing potential damage to biological samples. The localized cooling effect was validated by simulations, bench testing, and MR imaging experiments. Using this cryo-cooled planar coil system inside a 4.7 Tesla MR system resulted in an average image SNR enhancement of 1.47 ± 0.11 times relative to similar room-temperature coils. PMID:21603723

Multi-Resolution Rapid Prototyping of Vehicle Cooling Systems: Approach and Test Results

DTIC Science & Technology

2014-08-01

where the A/C was working. Figure 21: Comparison model/experiment for condenser refrigerant power; heat transfer factor = 0.8 The figure...previously. To demonstrate stable interactions with a more realistic environment, we have connected the four heat exchangers (two radiators, condenser ...simulations of any vehicle (or other) cooling systems. It can be seen that the underHood heat exchangers (transaxle radiator, condenser and ICE

Evaluation of malodor for automobile air conditioner evaporator by using laboratory-scale test cooling bench.

PubMed

Kim, Kyung Hwan; Kim, Sun Hwa; Jung, Young Rim; Kim, Man Goo

2008-09-12

As one of the measures to improve the environment in an automobile, malodor caused by the automobile air-conditioning system evaporator was evaluated and analyzed using laboratory-scale test cooling bench. The odor was simulated with an evaporator test cooling bench equipped with an airflow controller, air temperature and relative humidity controller. To simulate the same odor characteristics that occur from automobiles, one previously used automobile air conditioner evaporator associated with unpleasant odors was selected. The odor was evaluated by trained panels and collected with aluminum polyester bags. Collected samples were analyzed by thermal desorption into a cryotrap and subsequent gas chromatographic separation, followed by simultaneous olfactometry, flame ionization detector and identified by atomic emission detection and mass spectrometry. Compounds such as alcohols, aldehydes, and organic acids were identified as responsible odor-active compounds. Gas chromatography/flame ionization detection/olfactometry combined sensory method with instrumental analysis was very effective as an odor evaluation method in an automobile air-conditioning system evaporator.

Flightweight radiantly and actively cooled panel: Thermal and structural performance

NASA Technical Reports Server (NTRS)

Shore, C. P.; Nowak, R. J.; Kelly, H. N.

1982-01-01

A 2- by 4-ft flightweight panel was subjected to thermal/structural tests representative of design flight conditions for a Mach 6.7 transport and to off-design conditions simulating flight maneuvers and cooling system failures. The panel utilized Rene 41 heat shields backed by a thin layer of insulation to radiate away most of the 12 Btu/ft2-sec incident heating. A solution of ethylene glycol in water circulating through tubes in an aluminum-honeycomb-sandwich panel absorbed the remainder of the incident heating (0.8 Btu/sq ft-sec). The panel successfully withstood (1) 46.7 hr of radiant heating which included 53 thermal cycles and 5000 cycles of uniaxial inplane loading of + or - 1200 lfb/in; (2) simulated 2g-maneuver heating conditions and simulated cooling system failures without excessive temperatures on the structural panel; and (3) the extensive thermal/structural tests and the aerothermal tests reported in NASA TP-1595 without significant damage to the structural panel, coolant leaks, or hot-gas ingress to the structural panel.

Design, fabrication and test of Load Bearing multilayer insulation to support a broad area cooled shield

NASA Astrophysics Data System (ADS)

Dye, S. A.; Johnson, W. L.; Plachta, D. W.; Mills, G. L.; Buchanan, L.; Kopelove, A. B.

2014-11-01

Improvements in cryogenic propellant storage are needed to achieve reduced or Zero Boil Off of cryopropellants, critical for long duration missions. Techniques for reducing heat leak into cryotanks include using passive multi-layer insulation (MLI) and vapor cooled or actively cooled thermal shields. Large scale shields cannot be supported by tank structural supports without heat leak through the supports. Traditional MLI also cannot support shield structural loads, and separate shield support mechanisms add significant heat leak. Quest Thermal Group and Ball Aerospace, with NASA SBIR support, have developed a novel Load Bearing multi-layer insulation (LBMLI) capable of self-supporting thermal shields and providing high thermal performance. We report on the development of LBMLI, including design, modeling and analysis, structural testing via vibe and acoustic loading, calorimeter thermal testing, and Reduced Boil-Off (RBO) testing on NASA large scale cryotanks. LBMLI uses the strength of discrete polymer spacers to control interlayer spacing and support the external load of an actively cooled shield and external MLI. Structural testing at NASA Marshall was performed to beyond maximum launch profiles without failure. LBMLI coupons were thermally tested on calorimeters, with superior performance to traditional MLI on a per layer basis. Thermal and structural tests were performed with LBMLI supporting an actively cooled shield, and comparisons are made to the performance of traditional MLI and thermal shield supports. LBMLI provided a 51% reduction in heat leak per layer over a previously tested traditional MLI with tank standoffs, a 38% reduction in mass, and was advanced to TRL5. Active thermal control using LBMLI and a broad area cooled shield offers significant advantages in total system heat flux, mass and structural robustness for future Reduced Boil-Off and Zero Boil-Off cryogenic missions with durations over a few weeks.

A novel personal cooling system (PCS) incorporated with phase change materials (PCMs) and ventilation fans: An investigation on its cooling efficiency.

PubMed

Lu, Yehu; Wei, Fanru; Lai, Dandan; Shi, Wen; Wang, Faming; Gao, Chuansi; Song, Guowen

2015-08-01

Personal cooling systems (PCS) have been developed to mitigate the impact of severe heat stress for humans working in hot environments. It is still a great challenge to develop PCSs that are portable, inexpensive, and effective. We studied the performance of a new hybrid PCS incorporating both ventilation fans and phase change materials (PCMs). The cooling efficiency of the newly developed PCS was investigated on a sweating manikin in two hot conditions: hot humid (HH, 34°C, 75% RH) and hot dry (HD, 34°C, 28% RH). Four test scenarios were selected: fans off with no PCMs (i.e., Fan-off, the CONTROL), fans on with no PCMs (i.e., Fan-on), fans off with fully solidified PCMs (i.e., PCM+Fan-off), and fans on with fully solidified PCMs (i.e., PCM+Fan-on). It was found that the addition of PCMs provided a 54∼78min cooling in HH condition. In contrast, the PCMs only offered a 19-39min cooling in HD condition. In both conditions, the ventilation fans greatly enhanced the evaporative heat loss compared with Fan-off. The hybrid PCS (i.e., PCM+Fan-on) provided a continuous cooling effect during the three-hour test and the average cooling rate for the whole body was around 111 and 315W in HH and HD conditions, respectively. Overall, the new hybrid PCS may be an effective means of ameliorating symptoms of heat stress in both hot-humid and hot-dry environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pesaran, A.A.; Penney, T.R.; Czanderna, A.W.

The objectives of this document are to present an overview of the work accomplished to date on desiccant cooling to provide assessment of the state of the art of desiccant cooling technology in the field of desiccant material dehumidifier components, desiccant systems, and models. The report also discusses the factors that affect the widespread acceptance of desiccant cooling technology. This report is organized as follows. First, a basic description and historical overview of desiccant cooling technology is provided. Then, the recent research and development (R&D) program history (focusing on DOE`s funded efforts) is discussed. The status of the technology elementsmore » (materials, components, systems) is discussed in detail and a preliminary study on the energy impact of desiccant technology is presented. R&D needs for advancing the technology in the market are identified. The National Renewable Energy Laboratory`s unique desiccant test facilities and their typical outputs are described briefly. Finally, the results of a comprehensive literature search on desiccant cooling are presented in a bibliography. The bibliography contains approximately 900 citations on desiccant cooling.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pesaran, A.A.; Penney, T.R.; Czanderna, A.W.

The objectives of this document are to present an overview of the work accomplished to date on desiccant cooling to provide assessment of the state of the art of desiccant cooling technology in the field of desiccant material dehumidifier components, desiccant systems, and models. The report also discusses the factors that affect the widespread acceptance of desiccant cooling technology. This report is organized as follows. First, a basic description and historical overview of desiccant cooling technology is provided. Then, the recent research and development (R D) program history (focusing on DOE's funded efforts) is discussed. The status of the technologymore » elements (materials, components, systems) is discussed in detail and a preliminary study on the energy impact of desiccant technology is presented. R D needs for advancing the technology in the market are identified. The National Renewable Energy Laboratory's unique desiccant test facilities and their typical outputs are described briefly. Finally, the results of a comprehensive literature search on desiccant cooling are presented in a bibliography. The bibliography contains approximately 900 citations on desiccant cooling.« less

1 K cryostat with sub-millikelvin stability based on a pulse-tube cryocooler

NASA Astrophysics Data System (ADS)

DeMann, A.; Mueller, Sara; Field, S. B.

2016-01-01

A cryogenic system has been designed and tested that reaches a temperature below 1.1 K, with an rms temperature stability of 25 μ K. In this system a commercial pulse-tube cryocooler is used to liquify helium gas supplied from an external source. This liquid helium enters a 1 K pot through a large-impedance capillary tube, similar to a conventional 1 K system operated from a liquid helium bath. Unlike a conventional system, however, the molar flow rate of the system can be varied by changing the pressure of the incoming helium. This allows for a trade-off between helium usage and cooling power, which has a maximum value of 27 mW. The measured cooling power and fraction of helium exiting the capillary as liquid agree well with predictions based on an isenthalpic model of helium flow through the capillary. The system is simple to use and inexpensive to operate: The system can be cooled to base temperature in about 3 h and, with a flow rate giving a cooling power of 13 mW, the helium cost is around 6 per day.

Practices for Alleviating Heat Stress of Dairy Cows in Humid Continental Climates: A Literature Review

PubMed Central

Fournel, Sébastien; Ouellet, Véronique; Charbonneau, Édith

2017-01-01

Simple Summary The severity of heat stress issues on dairy cows will increase as global warming progresses. Fortunately, major advances in environmental management, including fans, misters, sprinklers, and cooled waterbeds, can attenuate the effects of thermal stress on cow health, production, and reproduction. These cooling systems were, however, tested in subtropical areas and their efficiency in northern regions is uncertain. This article assesses the potential of existing technologies to cool cows in humid continental climates through calculation of heat stress indices. Abstract Heat stress negatively affects the health and performance of dairy cows, resulting in considerable economic losses for the industry. In future years, climate change will exacerbate these losses by making the climate warmer. Physical modification of the environment is considered to be the primary means of reducing adverse effects of hot weather conditions. At present, to reduce stressful heat exposure and to cool cows, dairy farms rely on shade screens and various forms of forced convection and evaporative cooling that may include fans and misters, feed-line sprinklers, and tunnel- or cross-ventilated buildings. However, these systems have been mainly tested in subtropical areas and thus their efficiency in humid continental climates, such as in the province of Québec, Canada, is unclear. Therefore, this study reviewed the available cooling applications and assessed their potential for northern regions. Thermal stress indices such as the temperature-humidity index (THI) were used to evaluate the different cooling strategies. PMID:28468329

Development of Passive Fuel Cell Thermal Management Technology

NASA Technical Reports Server (NTRS)

Burke, Kenneth A.; Jakupca, Ian; Colozza, Anthony

2011-01-01

The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA exploration program. The passive thermal management system relies on heat conduction within the cooling plate to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack rather than using a pumped loop cooling system to convectively remove the heat. Using the passive approach eliminates the need for a coolant pump and other cooling loop components which reduces fuel cell system mass and improves overall system reliability. Previous analysis had identified that low density, ultra-high thermal conductivity materials would be needed for the cooling plates in order to achieve the desired reductions in mass and the highly uniform thermal heat sink for each cell within a fuel cell stack. A pyrolytic graphite material was identified and fabricated into a thin plate using different methods. Also a development project with Thermacore, Inc. resulted in a planar heat pipe. Thermal conductivity tests were done using these materials. The results indicated that lightweight passive fuel cell cooling is feasible.

EVA space suit Evaporative Cooling/Heating Glove System (ECHGS)

NASA Technical Reports Server (NTRS)

Coss, F. A.

1976-01-01

A new astronaut glove, the Evaporative Cooling/Heating Glove System (ECHGS), was designed and developed to allow the handling of objects between -200 F and +200 F. Active heating elements, positioned at each finger pad, provide additional heat to the finger pads from the rest of the finger. A water evaporative cooling system provides cooling by the injection of water to the finger areas and the subsequent direct evaporation to space. Thin, flexible insulation has been developed for the finger areas to limit thermal conductivity. Component and full glove tests have shown that the glove meets and exceeds the requirements to hold a 11/2 inch diameter bar at + or - 200 F for three minutes within comfort limits. The ECHGS is flexible, lightweight and comfortable. Tactility is reasonable and small objects can be identified especially by the fingertips beyond the one half width active elements.

A LWIR hyperspectral imager using a Sagnac interferometer and cooled HgCdTe detector array

NASA Astrophysics Data System (ADS)

Lucey, Paul G.; Wood, Mark; Crites, Sarah T.; Akagi, Jason

2012-06-01

LWIR hyperspectral imaging has a wide range of civil and military applications with its ability to sense chemical compositions at standoff ranges. Most recent implementations of this technology use spectrographs employing varying degrees of cryogenic cooling to reduce sensor self-emission that can severely limit sensitivity. We have taken an interferometric approach that promises to reduce the need for cooling while preserving high resolution. Reduced cooling has multiple benefits including faster system readiness from a power off state, lower mass, and potentially lower cost owing to lower system complexity. We coupled an uncooled Sagnac interferometer with a 256x320 mercury cadmium telluride array with an 11 micron cutoff to produce a spatial interferometric LWIR hyperspectral imaging system operating from 7.5 to 11 microns. The sensor was tested in ground-ground applications, and from a small aircraft producing spectral imagery including detection of gas emission from high vapor pressure liquids.

Personal cooling in nuclear power stations. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamon, E.

1983-03-01

Two approaches to personal, non-restrictive cooling of workers exposed to high-temperature work environments in nuclear power plants were evaluated. Both approaches involved a cooling garment designed to be worn under the protective clothing donned in penetration into radiation areas. One garmet was developed to cool by direct body contact with small packets of frozen water enclosed in the pockets of a shirt. The other garmets cooled by circulating a cooled liquid through capillaries in a vest and head cap (System A) or a vest (System B). Testing was conducted in a laboratory simulation of high ambient temperature (55/sup 0/C) andmore » moderate metabolic heat production (200 to 300 kcal/h). Exposure time without cooling (control) was 52 minutes (Group 1) for the workloads demanding 200 kcal/h (48 minutes for Group 2). A long garmet with 7.2 kg of frozen water (LFWG) increased mean exposure time over the control by 242% (163% for the same garmet with 6.2 kg of frozen water). A short-version garmet with 3.8 kg of frozen water (SFWG) increased the stay time by 115%. The circulating-liquid garmets increased mean exposure time 35% (System A) and 27% (System B) over the control. In field observation, the LFWG with 6.2 kg of frozen water improved stay time by 125%.« less

Prototype solar heating and cooling systems

NASA Technical Reports Server (NTRS)

1978-01-01

Eight prototype systems were developed. The systems are 3, 25, and 75-ton size units. The manufacture, test, installation, maintenance, problem resolution, and performance evaluation of the systems is described. Size activities for the various systems are included.

Turbine airfoil cooling system with cooling systems using high and low pressure cooling fluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marsh, Jan H.; Messmann, Stephen John; Scribner, Carmen Andrew

A turbine airfoil cooling system including a low pressure cooling system and a high pressure cooling system for a turbine airfoil of a gas turbine engine is disclosed. In at least one embodiment, the low pressure cooling system may be an ambient air cooling system, and the high pressure cooling system may be a compressor bleed air cooling system. In at least one embodiment, the compressor bleed air cooling system in communication with a high pressure subsystem that may be a snubber cooling system positioned within a snubber. A delivery system including a movable air supply tube may be usedmore » to separate the low and high pressure cooling subsystems. The delivery system may enable high pressure cooling air to be passed to the snubber cooling system separate from low pressure cooling fluid supplied by the low pressure cooling system to other portions of the turbine airfoil cooling system.« less

Simulation of an active cooling system for photovoltaic modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdelhakim, Lotfi

Photovoltaic cells are devices that convert solar radiation directly into electricity. However, solar radiation increases the photovoltaic cells temperature [1] [2]. The temperature has an influence on the degradation of the cell efficiency and the lifetime of a PV cell. This work reports on a water cooling technique for photovoltaic panel, whereby the cooling system was placed at the front surface of the cells to dissipate excess heat away and to block unwanted radiation. By using water as a cooling medium for the photovoltaic solar cells, the overheating of closed panel is greatly reduced without prejudicing luminosity. The water alsomore » acts as a filter to remove a portion of solar spectrum in the infrared band but allows transmission of the visible spectrum most useful for the PV operation. To improve the cooling system efficiency and electrical efficiency, uniform flow rate among the cooling system is required to ensure uniform distribution of the operating temperature of the PV cells. The aims of this study are to develop a 3D thermal model to simulate the cooling and heat transfer in Photovoltaic panel and to recommend a cooling technique for the PV panel. The velocity, pressure and temperature distribution of the three-dimensional flow across the cooling block were determined using the commercial package, Fluent. The second objective of this work is to study the influence of the geometrical dimensions of the panel, water mass flow rate and water inlet temperature on the flow distribution and the solar panel temperature. The results obtained by the model are compared with experimental results from testing the prototype of the cooling device.« less

Improving the viability and versatility of the E × B probe with an active cooling system.

PubMed

Liu, Lihui; Cai, Guobiao; You, Fengyi; Ren, Xiang; Zheng, Hongru; He, Bijiao

2018-04-01

A thermostatic E × B probe is designed to protect the probe body from the thermal effect of the plasma plume that has a significant influence on the resolution of the probe for high-power electric thrusters. An active cooling system, which consists of a cooling panel and carbon fiber felts combined with a recycling system of liquid coolants or an open-type system of gas coolants, is employed to realize the protection of the probe. The threshold for the design parameters for the active cooling system is estimated by deriving the energy transfer of the plasma plume-probe body interaction and the energy taken away by the coolants, and the design details are explained. The diagnostics of the LIPS-300 ion thruster with a power of 3 kW and a screen-grid voltage of 1450 V was implemented by the designed thermostatic E × B probe. The measured spectra illustrate that the thermostatic E × B probe can distinguish the fractions of Xe + ions and Xe 2+ ions without areas of overlap. In addition, the temperature of the probe body was less than 306 K in the beam region of the plasma plume during the 200-min-long continuous test. A thermostatic E × B probe is useful for enhancing the viability and versatility of equipment and for reducing uneconomical and complex test procedures.

Improving the viability and versatility of the E × B probe with an active cooling system

NASA Astrophysics Data System (ADS)

Liu, Lihui; Cai, Guobiao; You, Fengyi; Ren, Xiang; Zheng, Hongru; He, Bijiao

2018-04-01

A thermostatic E × B probe is designed to protect the probe body from the thermal effect of the plasma plume that has a significant influence on the resolution of the probe for high-power electric thrusters. An active cooling system, which consists of a cooling panel and carbon fiber felts combined with a recycling system of liquid coolants or an open-type system of gas coolants, is employed to realize the protection of the probe. The threshold for the design parameters for the active cooling system is estimated by deriving the energy transfer of the plasma plume-probe body interaction and the energy taken away by the coolants, and the design details are explained. The diagnostics of the LIPS-300 ion thruster with a power of 3 kW and a screen-grid voltage of 1450 V was implemented by the designed thermostatic E × B probe. The measured spectra illustrate that the thermostatic E × B probe can distinguish the fractions of Xe+ ions and Xe2+ ions without areas of overlap. In addition, the temperature of the probe body was less than 306 K in the beam region of the plasma plume during the 200-min-long continuous test. A thermostatic E × B probe is useful for enhancing the viability and versatility of equipment and for reducing uneconomical and complex test procedures.

Stimulatory effect of cooling tower biocides on amoebae.

PubMed

Srikanth, S; Berk, S G

1993-10-01

Two species of amoebae were isolated from the cooling tower of an air-conditioning system and examined for effects of exposure to four cooling tower biocides, a thiocarbamate compound, tributyltin neodecanoate mixed with quaternary ammonium compounds, another quaternary ammonium compound alone, and an isothiazolin derivative. The amoebae isolated were Acanthamoeba hatchetti and a Cochliopodium species. Two other amoeba cultures, an A. hatchetti culture and Cochliopodium bilimbosum, were obtained from the American Type Culture Collection (ATCC) and were also tested. The cooling tower isolates were more resistant to most of the biocides than the ATCC isolates were. The isothiazolin derivative was the least inhibitory to all four amoeba isolates, and tributyltin neodecanoate mixed with quaternary ammonium compounds was the most inhibitory to three of the four isolates. After exposure to lower concentrations of the biocides, including for one strain the manufacturer's recommended concentration of one biocide, the cooling tower amoeba populations increased significantly compared with unexposed controls, whereas the ATCC isolates were not stimulated at any of the concentrations tested. In some cases, concentrations which stimulated cooling tower amoebae inhibited the growth of the ATCC isolates. These results suggest that cooling tower amoebae may adapt to biocides, underscoring the need to use freshly isolated cooling tower organisms rather than organisms from culture collections for testing the efficacy of such biocides. The stimulatory effect of biocides on amoeba populations is an alarming observation, since these organisms may be reservoirs for legionellae. Biocides used to control microbial growth may actually enhance populations of host organisms for pathogenic bacteria.

High-Performance Bipropellant Engine

NASA Technical Reports Server (NTRS)

Biaglow, James A.; Schneider, Steven J.

1999-01-01

TRW, under contract to the NASA Lewis Research Center, has successfully completed over 10 000 sec of testing of a rhenium thrust chamber manufactured via a new-generation powder metallurgy. High performance was achieved for two different propellants, N2O4- N2H4 and N2O4 -MMH. TRW conducted 44 tests with N2O4-N2H4, accumulating 5230 sec of operating time with maximum burn times of 600 sec and a specific impulse Isp of 333 sec. Seventeen tests were conducted with N2O4-MMH for an additional 4789 sec and a maximum Isp of 324 sec, with a maximum firing duration of 700 sec. Together, the 61 tests totalled 10 019 sec of operating time, with the chamber remaining in excellent condition. Of these tests, 11 lasted 600 to 700 sec. The performance of radiation-cooled rocket engines is limited by their operating temperature. For the past two to three decades, the majority of radiation-cooled rockets were composed of a high-temperature niobium alloy (C103) with a disilicide oxide coating (R512) for oxidation resistance. The R512 coating practically limits the operating temperature to 1370 C. For the Earth-storable bipropellants commonly used in satellite and spacecraft propulsion systems, a significant amount of fuel film cooling is needed. The large film-cooling requirement extracts a large penalty in performance from incomplete mixing and combustion. A material system with a higher temperature capability has been matured to the point where engines are being readied for flight, particularly the 100-lb-thrust class engine. This system has powder rhenium (Re) as a substrate material with an iridium (Ir) oxidation-resistant coating. Again, the operating temperature is limited by the coating; however, Ir is capable of long-life operation at 2200 C. For Earth-storable bipropellants, this allows for the virtual elimination of fuel film cooling (some film cooling is used for thermal control of the head end). This has resulted in significant increases in specific impulse performance (15 to 20 sec). To determine the merits of a powder rhenium thrust chamber, Lewis On-Board Propulsion Branch directed TRW (under the Space Storable Rocket Technology Program and the High Pressure Earth Storable Rocket Technology Program) to design, fabricate, and test an engineering model to serve as a technology demonstrator.

Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

NASA Technical Reports Server (NTRS)

Camarda, Charles J.; Glass, David E.

1992-01-01

Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

NASA Astrophysics Data System (ADS)

Camarda, Charles J.; Glass, David E.

1992-10-01

Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems.

PubMed

Hsieh, Ming-Kai; Chien, Shih-Hsiang; Li, Heng; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

2011-09-01

Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y).

Heat transfer analysis of catheters used for localized tissue cooling to attenuate reperfusion injury.

PubMed

Merrill, Thomas L; Mitchell, Jennifer E; Merrill, Denise R

2016-08-01

Recent revascularization success for ischemic stroke patients using stentrievers has created a new opportunity for therapeutic hypothermia. By using short term localized tissue cooling interventional catheters can be used to reduce reperfusion injury and improve neurological outcomes. Using experimental testing and a well-established heat exchanger design approach, the ɛ-NTU method, this paper examines the cooling performance of commercially available catheters as function of four practical parameters: (1) infusion flow rate, (2) catheter location in the body, (3) catheter configuration and design, and (4) cooling approach. While saline batch cooling outperformed closed-loop autologous blood cooling at all equivalent flow rates in terms of lower delivered temperatures and cooling capacity, hemodilution, systemic and local, remains a concern. For clinicians and engineers this paper provides insights for the selection, design, and operation of commercially available catheters used for localized tissue cooling. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Reuse of Treated Internal or External Wastewaters in the Cooling Systems of Coal-Based Thermoelectric Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Radisav Vidic; David Dzombak; Ming-Kai Hsieh

2009-06-30

This study evaluated the feasibility of using three impaired waters - secondary treated municipal wastewater, passively treated abandoned mine drainage (AMD), and effluent from ash sedimentation ponds at power plants - for use as makeup water in recirculating cooling water systems at thermoelectric power plants. The evaluation included assessment of water availability based on proximity and relevant regulations as well as feasibility of managing cooling water quality with traditional chemical management schemes. Options for chemical treatment to prevent corrosion, scaling, and biofouling were identified through review of current practices, and were tested at bench and pilot-scale. Secondary treated wastewater ismore » the most widely available impaired water that can serve as a reliable source of cooling water makeup. There are no federal regulations specifically related to impaired water reuse but a number of states have introduced regulations with primary focus on water aerosol 'drift' emitted from cooling towers, which has the potential to contain elevated concentrations of chemicals and microorganisms and may pose health risk to the public. It was determined that corrosion, scaling, and biofouling can be controlled adequately in cooling systems using secondary treated municipal wastewater at 4-6 cycles of concentration. The high concentration of dissolved solids in treated AMD rendered difficulties in scaling inhibition and requires more comprehensive pretreatment and scaling controls. Addition of appropriate chemicals can adequately control corrosion, scaling and biological growth in ash transport water, which typically has the best water quality among the three waters evaluated in this study. The high TDS in the blowdown from pilot-scale testing units with both passively treated mine drainage and secondary treated municipal wastewater and the high sulfate concentration in the mine drainage blowdown water were identified as the main challenges for blowdown disposal. Membrane treatment (nanofiltration or reverse osmosis) can be employed to reduce TDS and sulfate concentrations to acceptable levels for reuse of the blowdown in the cooling systems as makeup water.« less

Cryogenic Boil-Off Reduction System Testing

NASA Technical Reports Server (NTRS)

Plachta, David W.; Johnson, Wesley L.; Feller, Jeffery

2014-01-01

The Cryogenic Boil-Off Reduction System was tested with LH2 and LOX in a vacuum chamber to simulate space vacuum and the temperatures of low Earth orbit. Testing was successful and results validated the scaling study model that predicts active cooling reduces upper stage cryogenic propulsion mass for loiter periods greater than 2 weeks.

Space Suit Portable Life Support System (PLSS) 2.0 Human-in-the-Loop (HITL) Testing

NASA Technical Reports Server (NTRS)

Watts, Carly; Vogel, Matthew

2016-01-01

The space suit Portable Life Support System (PLSS) 2.0 represents the second integrated prototype developed and tested to mature a design that uses advanced technologies to reduce consumables, improve robustness, and provide additional capabilities over the current state of the art. PLSS 2.0 was developed in 2012, with extensive functional evaluations and system performance testing through mid-2014. In late 2014, PLSS 2.0 was integrated with the Mark III space suit in an ambient laboratory environment to facilitate manned testing, designated PLSS 2.0 Human-in-the-Loop (HITL) testing, in which the PLSS prototype performed the primary life support functions, including suit pressure regulation, ventilation, carbon dioxide control, and cooling of the test subject and PLSS avionics. The intent of this testing was to obtain subjective test subject feedback regarding qualitative aspects of PLSS 2.0 performance such as thermal comfort, sounds, smells, and suit pressure fluctuations due to the cycling carbon dioxide removal system, as well as to collect PLSS performance data over a range of human metabolic rates from 500-3000 Btu/hr. Between October 27 and December 18, 2014, nineteen two-hour simulated EVA test points were conducted in which suited test subjects walked on a treadmill to achieve a target metabolic rate. Six test subjects simulated nominal and emergency EVA conditions with varied test parameters including metabolic rate profile, carbon dioxide removal control mode, cooling water temperature, and Liquid Cooling and Ventilation Garment (state of the art or prototype). The nineteen test points achieved more than 60 hours of test time, with 36 hours accounting for simulated EVA time. The PLSS 2.0 test article performed nominally throughout the test series, confirming design intentions for the advanced PLSS. Test subjects' subjective feedback provided valuable insight into thermal comfort and perceptions of suit pressure fluctuations that will influence future advanced PLSS design and testing strategies.

Influence of Chlorination and Choice of Materials on Fouling in Cooling Water System under Brackish Seawater Conditions

PubMed Central

Rajala, Pauliina; Bomberg, Malin; Huttunen-Saarivirta, Elina; Priha, Outi; Tausa, Mikko; Carpén, Leena

2016-01-01

Cooling systems remove heat from components and industrial equipment. Water cooling, employing natural waters, is typically used for cooling large industrial facilities, such as power plants, factories or refineries. Due to moderate temperatures, cooling water cycles are susceptible to biofouling, inorganic fouling and scaling, which may reduce heat transfer and enhance corrosion. Hypochlorite treatment or antifouling coatings are used to prevent biological fouling in these systems. In this research, we examine biofouling and materials’ degradation in a brackish seawater environment using a range of test materials, both uncoated and coated. The fouling and corrosion resistance of titanium alloy (Ti-6Al-4V), super austenitic stainless steel (254SMO) and epoxy-coated carbon steel (Intershield Inerta160) were studied in the absence and presence of hypochlorite. Our results demonstrate that biological fouling is intensive in cooling systems using brackish seawater in sub-arctic areas. The microfouling comprised a vast diversity of bacteria, archaea, fungi, algae and protozoa. Chlorination was effective against biological fouling: up to a 10–1000-fold decrease in bacterial and archaeal numbers was detected. Chlorination also changed the diversity of the biofilm-forming community. Nevertheless, our results also suggest that chlorination enhances cracking of the epoxy coating. PMID:28773597

Influence of Chlorination and Choice of Materials on Fouling in Cooling Water System under Brackish Seawater Conditions.

PubMed

Rajala, Pauliina; Bomberg, Malin; Huttunen-Saarivirta, Elina; Priha, Outi; Tausa, Mikko; Carpén, Leena

2016-06-15

Cooling systems remove heat from components and industrial equipment. Water cooling, employing natural waters, is typically used for cooling large industrial facilities, such as power plants, factories or refineries. Due to moderate temperatures, cooling water cycles are susceptible to biofouling, inorganic fouling and scaling, which may reduce heat transfer and enhance corrosion. Hypochlorite treatment or antifouling coatings are used to prevent biological fouling in these systems. In this research, we examine biofouling and materials' degradation in a brackish seawater environment using a range of test materials, both uncoated and coated. The fouling and corrosion resistance of titanium alloy (Ti-6Al-4V), super austenitic stainless steel (254SMO) and epoxy-coated carbon steel (Intershield Inerta160) were studied in the absence and presence of hypochlorite. Our results demonstrate that biological fouling is intensive in cooling systems using brackish seawater in sub-arctic areas. The microfouling comprised a vast diversity of bacteria, archaea, fungi, algae and protozoa. Chlorination was effective against biological fouling: up to a 10-1000-fold decrease in bacterial and archaeal numbers was detected. Chlorination also changed the diversity of the biofilm-forming community. Nevertheless, our results also suggest that chlorination enhances cracking of the epoxy coating.

Chandra Observations of MS0440.5+0204 & MS0839.9+2938: Cooling Flow Clusters in Formation?

NASA Astrophysics Data System (ADS)

McNamara, Brian

2000-09-01

We propose to observe two redshift z~0.2 clusters, MS0839.9+2938 and MS0440+0204, discovered as bright X-ray sources in the Einstein Medium Sensitivity Survey. The cluster cores are structured in the X-ray and optical bands, and they harbor large cooling flows. Their central cluster galaxies contain luminous nebular emission systems, active star formation, and strong radio sources. Using the Chandra data, we will determine whether the large discrepancies between the X-ray cooling rates and optical star formation rates can be reconciled, and we will test the hypothesis that cooling flows form as cool, dense groups accrete into massive clusters.

Physiological and Thermal Responses of MS Patients to Head and Vest Cooling: A Case Study

NASA Technical Reports Server (NTRS)

Luna, Bernadette; Webbon, Bruce W.; Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Kliss, Mark (Technical Monitor)

1997-01-01

Personal cooling systems are used to alleviate symptoms of multiple sclerosis (MS) and to prevent increased core temperature during daily activities. The objective of this study was to determine the operating characteristics and the physiologic changes produced by short term application of the stationary thermal control system used by most clinical institutions. The Life Enhancement Tech (LET) Mark VII portable cooling system and a lightweight Head-vest active cooling garment were used to cool the head and chest regions of 4 male and 3 female MS patients (30 to 66 yrs. old) in this study. The subjects, seated in an upright position at normal room temperature (approx. 24 C), were tested for 60 min. with the liquid cooling garment (LCG) operated at 50 F. Oral, right and left ear temperatures and cooling system parameters were logged manually every 5 min. Arm, leg, chest and rectal temperatures, heart rate, respiration, and an activity index were recorded continuously on a U.F.I., Inc., Biolog ambulatory monitor. All temperature responses showed extreme variation among subjects. The cold-sensitive subject's rectal temperature increased initially in response to cooling; the heat sensitive subject's rectal temperature decreased. After 40 min. of cooling and during recovery, all subjects'rectal temperatures decreased. Oral temperatures began to decrease after 30 min. of cooling. After 60 min. of cooling, temperature drops ranged from approx. 0.3 - 0.8 C. Oral temperatures continued to decrease during recovery (approx. 0.2 C). The car temperature of the heat sensitive subject was increased after cooling, other subjects exhibited an ear temperature decrease (0.0 - 0.5 C). These data indicate that head and vest cooling may be used to reduce the oral temperatures of MS patients by the approximate amount needed for symptomatic relief as shown by other researchers. The combination of a small subject population and a large subject variance does not permit us to draw statistical conclusions about the temperature response of MS patients. An individual's heat or cold sensitivity may influence their thermal response to cooling. This factor should be considered in the prescribed use of liquid cooling garments in the therapeutic management of MS.

Controlled cooling technology for bar and rod mills -- Computer simulation and operational results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mauk, P.J.; Kruse, M.; Plociennik, U.

The Controlled Cooling Technology (CCT) developed by SMS to simulate the rolling process and automatic control of the water cooling sections is presented. The Controlled Rolling and Cooling Technology (CRCT) model is a key part of the CCT system. It is used to simulate temperature management for the rolling stock on the computer before the actual rolling process takes place. This makes it possible to dispense with extensive rolling tests in the early stages of project planning and to greatly reduce the extent of such tests prior to the start of commercial production in a rolling mill. The CRCT modelmore » has been in use at Von Moos Stahl Ag for three years. It demonstrates that, by targeted improvement of the set-up values in both the technology and the plant, it is possible to improve microstructure quality and achieve better geometrical parameters in the rolled products. Also, the results gained with the CCT system in practical operation at the Kia Steel Bar Mill, Kunsan, Korea, are presented.« less

Environmental Assessment of 2005 Base Realignment and Closure Actions at Homestead Air Reserve Base, Florida

DTIC Science & Technology

2007-02-01

permit, there are no guidelines for storm water quality , therefore Homestead ARB established a program with the State of Florida to test and monitor... storm water quality . Heating and Cooling Systems. Because of the humid Florida climate, engineers are considering an installation-wide Utility... storm water quality , negligible effects on the storm water system would be expected as a result of the Proposed Action. Heating and Cooling

Development of an experimental system for characterization of high-temperature superconductors cooled by liquid hydrogen under the external magnetic field

NASA Astrophysics Data System (ADS)

Tatsumoto, H.; Shirai, Y.; Shiotsu, M.; Naruo, Y.; Kobayashi, H.; Inatani, Y.

2014-05-01

An experimental system has been developed to investigate electro-magnetic properties of high-Tc superconductors cooled by liquid hydrogen under the external magnetic field of up to 7 T. A LH2 cryostat is concentrically mounted on the inside of a LHe cryostat to cool a NbTi superconducting magnet. The experimental system is installed in an explosion-proof room. Explosion proof electrical devices are used and current leads are covered with an enclosure filled with nitrogen gas. A remote control system has been developed. Furthermore, the effects of stray magnetic field on the existing and the new devices are investigated and electro-magnetic shielding panels and enclosure made of iron were designed. It is confirmed through the cryogenic test that the experimental system meets the design requirements.

Hubble Space Telescope Program on STS-95 Supported by Space Acceleration Measurement System for Free Flyers

NASA Technical Reports Server (NTRS)

Kacpura, Thomas J.

2000-01-01

John Glenn's historic return to space was a primary focus of the STS 95 space shuttle mission; however, the 83 science payloads aboard were the focus of the flight activities. One of the payloads, the Hubble Space Telescope Orbital System Test (HOST), was flown in the cargo bay by the NASA Goddard Space Flight Center. It served as a space flight test of upgrade components for the telescope before they are installed in the shuttle for the next Hubble Space Telescope servicing mission. One of the upgrade components is a cryogenic cooling system for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). The cooling is required for low noise in the receiver's sensitive electronic instrumentation. Originally, a passive system using dry ice cooled NICMOS, but the ice leaked away and must be replaced. The active cryogenic cooler can provide the cold temperatures required for the NICMOS, but there was a concern that it would create vibrations that would affect the fine pointing accuracy of the Hubble platform.

Proof-of-Concept Testing of the Passive Cooling System (T-CLIP™) for Solar Thermal Applications at an Elevated Temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Seung Jun; Quintana, Donald L.; Vigil, Gabrielle M.

2015-11-30

The Applied Engineering and Technology-1 group (AET-1) at Los Alamos National Laboratory (LANL) conducted the proof-of-concept tests of SolarSPOT LLC’s solar thermal Temperature- Clipper, or T-CLIP™ under controlled thermal conditions using a thermal conditioning unit (TCU) and a custom made environmental chamber. The passive T-CLIP™ is a plumbing apparatus that attaches to a solar thermal collector to limit working fluid temperature and to prevent overheating, since overheating may lead to various accident scenarios. The goal of the current research was to evaluate the ability of the T-CLIP™ to control the working fluid temperature by using its passive cooling mechanism (i.e.more » thermosiphon, or natural circulation) in a small-scale solar thermal system. The assembled environmental chamber that is thermally controlled with the TCU allows one to simulate the various possible weather conditions, which the solar system will encounter. The performance of the T-CLIP™ was tested at two different target temperatures: 1) room temperature (70 °F) and 2) an elevated temperature (130 °F). The current test campaign demonstrated that the T-CLIP™ was able to prevent overheating by thermosiphon induced cooling in a small-scale solar thermal system. This is an important safety feature in situations where the pump is turned off due to malfunction or power outages.« less

Regeneratively Cooled Liquid Oxygen/Methane Technology Development

NASA Technical Reports Server (NTRS)

Robinson, Joel W.; Greene, Christopher B.; Stout, Jeffrey

2012-01-01

The National Aeronautics & Space Administration (NASA) has identified Liquid Oxygen (LOX)/Liquid Methane (LCH4) as a potential propellant combination for future space vehicles based upon exploration studies. The technology is estimated to have higher performance and lower overall systems mass compared to existing hypergolic propulsion systems. NASA-Marshall Space Flight Center (MSFC) in concert with industry partner Pratt & Whitney Rocketdyne (PWR) utilized a Space Act Agreement to test an oxygen/methane engine system in the Summer of 2010. PWR provided a 5,500 lbf (24,465 N) LOX/LCH4 regenerative cycle engine to demonstrate advanced thrust chamber assembly hardware and to evaluate the performance characteristics of the system. The chamber designs offered alternatives to traditional regenerative engine designs with improvements in cost and/or performance. MSFC provided the test stand, consumables and test personnel. The hot fire testing explored the effective cooling of one of the thrust chamber designs along with determining the combustion efficiency with variations of pressure and mixture ratio. The paper will summarize the status of these efforts.

KSC-02pd0031

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility help guide the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System onto a payload carrier. NICMOS II is part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. It is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

KSC-02pd0037

NASA Image and Video Library

2002-01-22

KENNEDY SPACE CENTER, FLA. -- The NICMOS II radiator is ready for checkout in the Vertical Processing Facility. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System is part of the payload on mission STS-109, the Hubble Servicing Telescope mission. NICMOS is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. NICMOS could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of Columbia is scheduled Feb. 28, 2002

KSC-02pd0033

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System rests inside a protective enclosure on a payload carrier. NICMOS II is part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. It is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

KSC-02pd0025

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility wheel a container with the NICMOS II across the floor. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System is part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. NICMOS is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

Testing of a Methane Cryogenic Heat Pipe with a Liquid Trap Turn-Off Feature for use on Space Interferometer Mission (SIM)

NASA Technical Reports Server (NTRS)

Cepeda-Rizo, Juan; Krylo, Robert; Fisher, Melanie; Bugby, David C.

2011-01-01

Camera cooling for SIM presents three thermal control challenges; stable operation at 163K (110 C), decontamination heating to +20 C, and a long span from the cameras to the radiator. A novel cryogenic cooling system based on a methane heat pipe meets these challenges. The SIM thermal team, with the help of heat pipe vendor ATK, designed and tested a complete, low temperature, cooling system. The system accommodates the two SIM cameras with a double-ended conduction bar, a single methane heat pipe, independent turn-off devices, and a flight-like radiator. The turn ]off devices consist of a liquid trap, for removing the methane from the pipe, and an electrical heater to raise the methane temperature above the critical point thus preventing two-phase operation. This is the first time a cryogenic heat pipe has been tested at JPL and is also the first heat pipe to incorporate the turn-off features. Operation at 163K with a methane heat pipe is an important new thermal control capability for the lab. In addition, the two turn-off technologies enhance the "bag of tricks" available to the JPL thermal community. The successful test program brings this heat pipe to a high level of technology readiness.

Thermal performance of the CrIS passive cryocooler

NASA Astrophysics Data System (ADS)

Ghaffarian, B.; Kohrman, R.; Magner, A.

2006-02-01

The configuration, performance, and test validation of a passive radiant cooler for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Crosstrack Infrared Sounder (CrIS) Instrument are presented. The cooler is required to provide cryogenic operation of IR focal planes. The 11 kg device, based on prior ITT Industries Space Systems Division coolers, requires virtually no power. It uses multiple thermally isolated cooling stages, each with an independent cryoradiator, operating at successively colder temperatures. The coldest stage, with a controlled set point at 81 K, cools a longwave IR (LWIR) focal plane. An intermediate stage, with a 98 K control point, cools detectors operating in MWIR and SWIR spectral regions. The warmest stage includes a fixed, integral earth shield that limits the thermal load from the earth in the NPOESS Operational Low-earth Orbiting (LEO) orbit. A study of the thermal balance and loads analysis used to evaluate the predicted cooler performance is discussed. High performance margins have been retained throughout the cooler development, fabrication and test phases of the program. The achievable in-orbit temperatures for this cooler are anticipated to be 73 K for the LWIR cooling stage and 91 K for the midwave IR (MWIR)/shortwave IR (SWIR) stage. Test results from two iterations of thermal vacuum verification testing are presented. Lessons learned from the first test, which failed to produce the predicted performance are included. The thermal model of the cooler and test configuration was used to identify deficiencies in the test targets resulting in unexpected heat loads. Corrective action was implemented to remove the heat leaks and a second test verified both the cooler performance and the correlation of the detailed thermal model.

Electrochemical-Thermal Modeling and Microscale Phase Change for Passive Internal Thermal Management of Lithium Ion Batteries

NASA Astrophysics Data System (ADS)

Bandhauer, Todd Matthew

In the current investigation, a fully coupled electrochemical and thermal model for lithium-ion batteries is developed to investigate the effects of different thermal management strategies on battery performance. This work represents the first ever study of these coupled electrochemical-thermal phenomena in batteries from the electrochemical heat generation all the way to the dynamic heat removal in actual hybrid electric vehicles (HEV) drive cycles. In addition, a novel, passive internal cooling system that uses heat removal through liquid-vapor phase change is developed. The proposed cooling system passively removes heat almost isothermally with negligible thermal resistances between the heat source and cooling fluid, thereby allowing battery performance to improve unimpeded by thermal limitations. For the battery model, local electrochemical reaction rates are predicted using temperature-dependent data on a commercially available battery designed for high rates (C/LiFePO4) in a computationally efficient manner. Data were collected on this small battery (˜1 Ah) over a wide range of temperatures (10°C to 60°C), depths of discharge (0.15 Ah < DOD < 0.95 Ah), and rates (-5 A to 5 A) using two separate test facilities to maintain sufficient temperature fidelity and to discern the relative influence of reversible and irreversible heating. The results show that total volumetric heat generation is a primarily a function of current and DOD, and secondarily a function of temperature. The results also show that reversible heating is significant compared to irreversible heating, with a minimum of 7.5% of the total heat generation attributable to reversible heating at 5 A and 15°C. Additional tests show that these constant current data can be used to simulate the response of the battery to dynamic loading, which serves as the basis for the electrochemical-thermal model development. This model is then used to compare the effects of external and internal cooling on battery performance. The proposed internal cooling system utilizes microchannels inserted into the interior of the cell that contain a liquid-vapor phase change fluid for heat removal at the source of heat generation. Although there have been prior investigations of phase change at the microscales, fluid flow for pure refrigerants at low mass fluxes (G < 120 kg m-2 s-1) experienced in the passive internal cooling system is not well understood. Therefore, passive, thermally driven refrigerant (R134a) flow in a representative test section geometry (3.175 mm x 160 mm) is investigated using a surrogate heat source. Heat inputs were varied over a wide range of values representative of battery operating conditions (120 < Q˙m < 6500 W L-1 ). The measured mass flow rate and test section outlet quality from these experiments are utilized to accurately calculate the two-phase frictional pressure drop in the test section, which is the dominant flow loss in the passive system in most cases. The two-phase frictional pressure drop model is used to predict the performance of a simplified passive internal cooling system. This thermal-hydraulic performance model is coupled to the electrochemical-thermal model for performance assessment of two-scaled up HEV battery packs (9.6 kWh based on 8 Ah and 20 Ah cells) subjected to an aggressive highway dynamic simulation. This assessment is used to compare the impact of air, liquid, and edge external cooling on battery performance. The results show that edge cooling causes large thermal gradients inside the cells, leading to non-uniform cycling. Air cooling also causes unacceptable temperature rise, while liquid cooling is sufficient only for the pack based on the thinner 8 Ah cell. In contrast, internally cooled cells reduce peak temperature without imposing significant thermal gradients. As a result, packs with internal cooling can be cycled more aggressively, leading to higher charge and discharge energy extraction densities in spite of the volume increase due to 160 microm channels inserted into the 284.5 microm unit cell. Furthermore, the saturation temperature of the phase change fluid can be optimized to balance capacity fade and energy extraction at elevated temperatures. At a saturation temperature of 34°C, the energy extraction density was 80.2% and 66.7% greater than for the best externally cooled system (liquid) even when the pack volume increased due to incorporation of the channels. (Abstract shortened by UMI.)

Cryogenic testing of Planck sorption cooler test facility

NASA Technical Reports Server (NTRS)

Zhang, B.; Pearson, D.; Borders, J.; Franklin, B.; Prina, M.; Hardy, J.; Crumb, D.

2004-01-01

A test facility has been upgraded in preparation for testing of two hydrogen sorption cryocoolers operating at 18/20 K. these sorption coolers are currently under development at the Jet Propulsion Laboratory. This work summarizes the scope of the test facility upgrade, including design for cryogenic cooling power delivery, system thermal management, insulation schemes, and data acquisition techniques. Ground support equipment for the sorption coolers, structural features of the test chamber, and the vacuum system involved for system testing will also be described in detail.

Actively cooled plate fin sandwich structural panels for hypersonic aircraft

NASA Technical Reports Server (NTRS)

Smith, L. M.; Beuyukian, C. S.

1979-01-01

An unshielded actively cooled structural panel was designed for application to a hypersonic aircraft. The design was an all aluminum stringer-stiffened platefin sandwich structure which used a 60/40 mixture of ethylene glycol/water as the coolant. Eight small test specimens of the basic platefin sandwich concept and three fatigue specimens from critical areas of the panel design was fabricated and tested (at room temperature). A test panel representative of all features of the panel design was fabricated and tested to determine the combined thermal/mechanical performance and structural integrity of the system. The overall findings are that; (1) the stringer-stiffened platefin sandwich actively cooling concept results in a low mass design that is an excellent contender for application to a hypersonic vehicle, and (2) the fabrication processes are state of the art but new or modified facilities are required to support full scale panel fabrication.

Thermal and hydrodynamic studies for micro-channel cooling for large area silicon sensors in high energy physics experiments

NASA Astrophysics Data System (ADS)

Flaschel, Nils; Ariza, Dario; Díez, Sergio; Gerboles, Marta; Gregor, Ingrid-Maria; Jorda, Xavier; Mas, Roser; Quirion, David; Tackmann, Kerstin; Ullan, Miguel

2017-08-01

Micro-channel cooling initially aiming at small-sized high-power integrated circuits is being transferred to the field of high energy physics. Today's prospects of micro-fabricating silicon opens a door to a more direct cooling of detector modules. The challenge in high energy physics is to save material in the detector construction and to cool large areas. In this paper, we are investigating micro-channel cooling as a candidate for a future cooling system for silicon detectors in a generic research and development approach. The work presented in this paper includes the production and the hydrodynamic and thermal testing of a micro-channel equipped prototype optimized to achieve a homogeneous flow distribution. Furthermore, the device was simulated using finite element methods.

ATM C and D panel/EREP cooling system contamination problem. [on Skylab

NASA Technical Reports Server (NTRS)

Williamson, J. G.

1973-01-01

This report presents the history of a preflight contamination problem that occurred in the ATM C and D panel/EREP cooling system on the Skylab, the studies that were made to determine the cause of the problem, and corrective actions that were made prior to lift-off. The results of all the observations, analyses and laboratory testing indicated that the contamination came from one or more of the EREP tape recorder coldplates and was caused by some abnormal electrolytic action, either during bench testing or in the spacecraft. Studies indicate that no such electrolytic action is likely to occur under normal operating conditions.

Design and Fabrication of a Tank-Applied Broad Area Cooling Shield Coupon

NASA Technical Reports Server (NTRS)

Wood, J. J.; Middlemas, M. R.

2012-01-01

The small-scale broad area cooling (BAC) shield test panel represents a section of the cryogenic propellant storage and transfer ground test article, a flight-like cryogenic propellant storage tank. The test panel design includes an aluminum tank shell, primer, spray-on foam insulation, multilayer insulation (MLI), and BAC shield hardware. This assembly was sized to accurately represent the character of the MLI/BAC shield system, be quickly and inexpensively assembled, and be tested in the Marshall Space Flight Center Acoustic Test Facility. Investigating the BAC shield response to a worst-case launch dynamic load was the key purpose for developing the test article and performing the test. A preliminary method for structurally supporting the BAC shield using low-conductivity standoffs was designed, manufactured, and evaluated as part of the test. The BAC tube-standoff interface and unsupported BAC tube lengths were key parameters for evaluation. No noticeable damage to any system hardware element was observed after acoustic testing.

Thermal modeling of a secondary concentrator integrated with an open direct-absorption molten-salt volumetric receiver in a beam-down tower system

NASA Astrophysics Data System (ADS)

Lahlou, Radia; Armstrong, Peter; Grange, Benjamin; Almheiri, Saif; Calvet, Nicolas; Slocum, Alexander; Shamim, Tariq

2016-05-01

An upward-facing three-dimensional secondary concentrator, herein termed Final Optical Element (FOE), is designed to be used in a beam-down tower in combination with an open volumetric direct-absorption molten-salt receiver tank acting simultaneously as a thermal energy storage system. It allows reducing thermal losses from the open receiver by decreasing its aperture area while keeping minimal spillage losses. The FOE is exposed to high solar fluxes, a part of which is absorbed by its reflector material, leading to material degradation by overheating. Consequently, the FOE may require active cooling. A thermal model of the FOE under passive cooling mechanism is proposed as a first step to evaluate its sensitivity to some design parameters. Then, it will be used to evaluate the requirements for the active cooling system. The model provides insights on the FOE thermal behavior and highlights the effectiveness of a design modification on passive cooling enhancement. First prototype tests under reduced flux and with no active cooling will be used for model adjustment.

Test case specifications for coupled neutronics-thermal hydraulics calculation of Gas-cooled Fast Reactor

NASA Astrophysics Data System (ADS)

Osuský, F.; Bahdanovich, R.; Farkas, G.; Haščík, J.; Tikhomirov, G. V.

2017-01-01

The paper is focused on development of the coupled neutronics-thermal hydraulics model for the Gas-cooled Fast Reactor. It is necessary to carefully investigate coupled calculations of new concepts to avoid recriticality scenarios, as it is not possible to ensure sub-critical state for a fast reactor core under core disruptive accident conditions. Above mentioned calculations are also very suitable for development of new passive or inherent safety systems that can mitigate the occurrence of the recriticality scenarios. In the paper, the most promising fuel material compositions together with a geometry model are described for the Gas-cooled fast reactor. Seven fuel pin and fuel assembly geometry is proposed as a test case for coupled calculation with three different enrichments of fissile material in the form of Pu-UC. The reflective boundary condition is used in radial directions of the test case and vacuum boundary condition is used in axial directions. During these condition, the nuclear system is in super-critical state and to achieve a stable state (which is numerical representation of operational conditions) it is necessary to decrease the reactivity of the system. The iteration scheme is proposed, where SCALE code system is used for collapsing of a macroscopic cross-section into few group representation as input for coupled code NESTLE.

Cooling the center-of-mass motion of a diamond nanocrystal in a magneto-gravitational trap

NASA Astrophysics Data System (ADS)

Hsu, Jen-Feng

A magneto-gravitational trap for micro/nanometer sized diamagnetic particles, such as diamond nanocrystals, is tested and characterized. After exploring various other systems, such as a suspended graphene beam and an optical trap, this magneto-gravitational nanomechanical trapping system for diamond with nitrogen-vacancy (NV) centers presents unique advantages for experiments in fundamental quantum mechanics. Those include, for example, the generation of large quantum superposition states and tests of quantum gravity. Features are demonstrated for this system, such as stable and passive levitation from atmospheric pressure to high vacuum, low resonant frequencies and damping rates, and cooling of the center-of-mass motions to below 1 K. The construction of the trap, vacuum system, optics, and motion detection electronics are described in detail.

Design of energy efficient building with radiant slab cooling

NASA Astrophysics Data System (ADS)

Tian, Zhen

2007-12-01

Air-conditioning comprises a substantial fraction of commercial building energy use because of compressor-driven refrigeration and fan-driven air circulation. Core regions of large buildings require year-round cooling due to heat gains from people, lights and equipment. Negative environmental impacts include CO2 emissions from electric generation and leakage of ozone-depleting refrigerants. Some argue that radiant cooling simultaneously improves building efficiency and occupant thermal comfort, and that current thermal comfort models fail to reflect occupant experience with radiant thermal control systems. There is little field evidence to test these claims. The University of Calgary's Information and Communications Technology (ICT) Building, is a pioneering radiant slab cooling installation in North America. Thermal comfort and energy performance were evaluated. Measurements included: (1) heating and cooling energy use, (2) electrical energy use for lighting and equipment, and (3) indoor temperatures. Accuracy of a whole building energy simulation model was evaluated with these data. Simulation was then used to compare the radiant slab design with a conventional (variable air volume) system. The radiant system energy performance was found to be poorer mainly due to: (1) simultaneous cooling by the slab and heating by other systems, (2) omission of low-exergy (e.g., groundwater) cooling possible with the high cooling water temperatures possible with radiant slabs and (3) excessive solar gain and conductive heat loss due to the wall and fenestration design. Occupant thermal comfort was evaluated through questionnaires and concurrent measurement of workstation comfort parameters. Analysis of 116 sets of data from 82 occupants showed that occupant assessment was consistent with estimates based on current thermal comfort models. The main thermal comfort improvements were reductions in (1) local discomfort from draft and (2) vertical air temperature stratification. The analysis showed that integrated architectural and mechanical design is required to achieve the potential benefits of radiant slab cooling, including: (1) reduction of peak solar gain via windows through (a) avoiding large window-to-wall ratios and/or (b) exterior shading of windows, (2) use of low-quality cooling sources such as cooling towers and ground water, especially in cold, dry climates, and (3) coordination of system control to avoid simultaneous heating and cooling.

Experimental evaluation of an adaptive Joule–Thomson cooling system including silicon-microfabricated heat exchanger and microvalve components

PubMed Central

Zhu, Weibin; Park, Jong M.; White, Michael J.; Nellis, Gregory F.; Gianchandani, Yogesh B.

2011-01-01

This article reports the evaluation of a Joule–Thomson (JT) cooling system that combines two custom micromachined components—a Si/glass-stack recuperative heat exchanger and a piezoelectrically actuated expansion microvalve. With the microvalve controlling the flow rate, this system can modulate cooling to accommodate varying refrigeration loads. The perforated plate Si/glass heat exchanger is fabricated with a stack of alternating silicon plates and Pyrex glass spacers. The microvalve utilizes a lead zirconate titanate actuator to push a Si micromachined valve seat against a glass plate, thus modulating the flow passing through the gap between the valve seat and the glass plate. The fabricated heat exchanger has a footprint of 1×1 cm2 and a length of 35 mm. The size of the micromachined piezoelectrically actuated valve is about 1×1×1 cm3. In JT cooling tests, the temperature of the system was successfully controlled by adjusting the input voltage of the microvalve. When the valve was fully opened (at an input voltage of −30 V), the system cooled down to a temperature as low as 254.5 K at 430 kPa pressure difference between inlet and outlet at steady state and 234 K at 710 kPa in a transient state. The system provided cooling powers of 75 mW at 255 K and 150 mW at 258 K. Parasitic heat loads at 255 K are estimated at approximately 700 mW. PMID:21552354

IR window design for hypersonic missile seekers: thermal shock and cooling systems

NASA Astrophysics Data System (ADS)

Hingst, Uwe; Koerber, Stefan

2001-10-01

Infra-red (IR) seekers on missiles at high Mach-numbers in the lower tier air defence often suffer from degradation in performance due to aerothermodynamic effects. The kind and rate of degradation depends on the geometric design (shape) and location of the IR-window. Optimal design may reduce those effects but still misses to totally withstand the imposed thermal stresses (thermal shock). Proper thermal protection systems and/or window cooling systems will be needed. The first part of this paper deals particularly with passive IR- window design features to reduce the thermal stresses. A series of wind-tunnel testings focused on the thermal shock behavior of different IR-window shapes under critical flight conditions. The variation of typical design parameters demonstrates the available features to reduce thermal shock by passive ways. The second part presents active thermal stress reduction devices, e.g. an active cooling system. Among others the most efficient reduction of thermal heating is based on three components: A partial coverage of the IR-dome to protect most parts against heating effects, a rotating system bearing the IR-dome and a liquid spray-cooling system in the gap between the cover and the IR-dome. The hemispherical or pyramidal dome can be located either midways in the missile nose section or sideways on the structure. The liquid spray cooling system combines both, a heat exchange by fluid evaporation and a heat transfer by fluid and gas cross flow (convection), causing a low fluid consumption. Such a cooling system along with their driving parameters and the resulting analytical performance will be presented.

Cooled Ceramic Composite Panel Tested Successfully in Rocket Combustion Facility

NASA Technical Reports Server (NTRS)

Jaskowiak, Martha H.

2003-01-01

Regeneratively cooled ceramic matrix composite (CMC) structures are being considered for use along the walls of the hot-flow paths of rocket-based or turbine-based combined-cycle propulsion systems. They offer the combined benefits of substantial weight savings, higher operating temperatures, and reduced coolant requirements in comparison to components designed with traditional metals. These cooled structures, which use the fuel as the coolant, require materials that can survive aggressive thermal, mechanical, acoustic, and aerodynamic loads while acting as heat exchangers, which can improve the efficiency of the engine. A team effort between the NASA Glenn Research Center, the NASA Marshall Space Flight Center, and various industrial partners has led to the design, development, and fabrication of several types of regeneratively cooled panels. The concepts for these panels range from ultra-lightweight designs that rely only on CMC tubes for coolant containment to more maintainable designs that incorporate metal coolant containment tubes to allow for the rapid assembly or disassembly of the heat exchanger. One of the cooled panels based on an all-CMC design was successfully tested in the rocket combustion facility at Glenn. Testing of the remaining four panels is underway.

Effect of Cooling Units on the Performance of an Automotive Exhaust-Based Thermoelectric Generator

NASA Astrophysics Data System (ADS)

Su, C. Q.; Zhu, D. C.; Deng, Y. D.; Wang, Y. P.; Liu, X.

2017-05-01

Currently, automotive exhaust-based thermoelectric generators (AETEGs) are a hot topic in energy recovery. In order to investigate the influence of coolant flow rate, coolant flow direction and cooling unit arrangement in the AETEG, a thermoelectric generator (TEG) model and a related test bench are constructed. Water cooling is adopted in this study. Due to the non-uniformity of the surface temperature of the heat source, the coolant flow direction would affect the output performance of the TEG. Changing the volumetric flow rate of coolant can increase the output power of multi-modules connected in series or/and parallel as it can improve the temperature uniformity of the cooling unit. Since the temperature uniformity of the cooling unit has a strong influence on the output power, two cooling units are connected in series or parallel to research the effect of cooling unit arrangements on the maximum output power of the TEG. Experimental and theoretical analyses reveal that the net output power is generally higher with cooling units connected in parallel than cooling units connected in series in the cooling system with two cooling units.

40 CFR 86.160-00 - Exhaust emission test procedure for SC03 emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

....161-00. (ii) Turn on the solar heating system. (iii) All vehicle test phases of preconditioning, soak... percent relative humidity), a solar heat load intensity of 850 W/m2, and vehicle cooling air flow... all vehicle windows. (4) Connect the emission test sampling system to the vehicle's exhaust tail pipe...

Development of a 30-50 K dual-stage pulse tube space cooler

NASA Astrophysics Data System (ADS)

Leenders, H.; de Jonge, G.; Mullié, J.; Prouvé, T.; Charles, I.; Trollier, T.; Tanchon, J.

2017-12-01

There has been a trend towards increasing heat loads for cryogenically cooled Earth Observation instruments in recent years. This is the case at both the current operational temperature levels (∼50K), as well as at lower operational temperature levels (30-50 K). One solution to meet this trend is to use existing pulse tube technology in a double stage configuration. With such technology increased cooling power at a lower temperature can be achieved at the payload detector. Another advantage of such a system is the possibility to increase overall system efficiency by cooling an intermediate shield to avoid parasitic heat losses towards the detector. Therefore a consortium consisting of Thales Cryogenics B.V. (TCBV), Alternative Energies and Atomic Energy Commission (CEA) and Absolut System (AS) is working on the development of a space cryostat actively cooled by a 2-stage high reliability pulse tube cryocooler. This work is being performed in the frame of an European Space Agency (ESA) Technical Research Program (TRP) (refer 4000109933/14/NL/RA) with a target TRL of 6. This paper presents the design of the overall equipped cryostat and cryostat itself but is mainly focused on the 2-stage cryocooler. Design, manufacturing and test aspects of cryocooler and its the lower level components such as the compressor and cold finger are discussed in detail in this paper. The cryocooler test campaign is meanwhile in final stages of completion and the obtained test results are in line with program objectives.

A comparison of imaging methods for use in an array biosensor

NASA Technical Reports Server (NTRS)

Golden, Joel P.; Ligler, Frances S.

2002-01-01

An array biosensor has been developed which uses an actively-cooled, charge-coupled device (CCD) imager. In an effort to save money and space, a complementary metal-oxide semiconductor (CMOS) camera and photodiode were tested as replacements for the cooled CCD imager. Different concentrations of CY5 fluorescent dye in glycerol were imaged using the three different detection systems with the same imaging optics. Signal discrimination above noise was compared for each of the three systems.

Development of the ITER ICH Transmission Line and Matching System

NASA Astrophysics Data System (ADS)

Rasmussen, D. A.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Swain, D. W.; Fredd, E. H.; Hosea, J.; Greenough, N.

2011-10-01

The ITER Ion Cyclotron Heating (ICH) System is designed to couple 20 MW of heating power for ion and electron heating. Prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system are being designed and tested. The ICH transmission lines are pressurized 300 mm diameter coaxial lines with water-cooled aluminum outer conductor and gas-cooled and water-cooled copper inner conductor. Each ICH transmission line is designed to handle 40-55 MHz power at up to 6 MW/line. A total of 8 lines split to 16 antenna inputs on two ICH antennas. Industrial suppliers have designed coaxial transmission line and matching components and prototypes will be manufactured. The prototype components will be qualified on a test stand operating at the full power and pulse length needed for ITER. The matching system must accommodated dynamic changes in the plasma loading due to ELMS and the L to H-mode transition. Passive ELM tolerance will be performed using hybrid couplers and loads, which can absorb the transient reflected power. The system is also designed to compensate for the mutual inductances of the antenna current straps to limit the peak voltages on the antenna array elements.

Helium Transfer System for the Superconducting Devices at NSRRC

NASA Astrophysics Data System (ADS)

Li, H. C.; Hsiao, F. Z.; Chang, S. H.; Chiou, W. S.

2006-04-01

A helium cryogenic plant with a maximum cooling power of 450 W at 4.5K was installed at the end of the year 2003. This plant has provide the cooling power for the test of one superconducting cavity and the commission of one superconducting magnet for nine months. In November 2004, we installed one helium transfer system in NSRRC's storage ring to fulfill the cooling requirement for the operation of one superconducting cavity and two superconducting magnets. This helium transfer system consists of a switch valve box and the nitrogen-shielding multi-channel transfer lines. The averaged heat leak to the helium process line (including the straight section, the joint, the elbow, the coupling) at liquid helium temperature is specified to be less than 0.1 W/m at 4.2K; the total heat leak of the switching valve box to helium process lines is less than 16 W at 4.2K. In this paper we present the function, design parameters and test result of the helium transfer system. Commissioning results of both the cavity and the magnets using this helium transfer system will be shown as well.

Development and testing of the Rho Sigma Incorporated microprocessor control subsystem

NASA Technical Reports Server (NTRS)

Hankins, J. D.

1979-01-01

Product development and performance tests of three programmable microprocessor controllers for use with solar heating and cooling systems are presented. The products were developed to be marketable for public use.

Study of Atomic Quasi-Stable States, Decoherence And Cooling of Mesoscale Particles

NASA Astrophysics Data System (ADS)

Zhong, Changchun

Quantum mechanics, since its very beginning, has totally changed the way we understand nature. The past hundred years have seen great successes in the application of quantum physics, including atomic spectra, laser technology, condensed matter physics and the remarkable possibility for quantum computing, etc. This thesis is dedicated to a small regime of quantum physics. In the first part of the thesis, I present the studies of atomic quasi-stable states, which refer to those Rydberg states of an atom that are relatively stable in the presence of strong fields. Through spectrally probing the quasi-stable states, series of survival peaks are found. If the quasi-stable electrons were created by ultraviolet (UV) lasers with two different frequencies, the survival peaks could be modulated by continuously changing the phase difference between the UV and the IR laser. The quantum simulation, through directly solving the Schrodinger equation, matches the experimental results performed with microwave fields, and our studies should provide a guidance for future experiments. Despite the huge achievements in the application of quantum theory, there are still some fundamental problems that remain unresolved. One of them is the so-called quantum-to-classical transition, which refers to the expectation that the system behaves in a more classical manner when the system size increases. This basic question was not well answered until decoherence theory was proposed, which states that the coherence of a quantum system tends to be destroyed by environmental interruptions. Thus, if a system is well isolated from its environment, it is in principle possible to observe macroscopic quantum coherence. Quite recently, testing quantum principles in the macroscale has become a hot topic due to rapic technological developments. A very promising platform for testing macroscale quantum physics is a laser levitated nanoparticle, and cooling its mechanical motion to the ground state is the first step. In the second part of this thesis, we develop the theory of decoherence for a mesoscopic system's rotational degrees of freedom. Combining decoherence in the translational degrees of freedom, the system's shot noise heating is discussed. We then focus on cooling the nanoparticle in the laser-shot-noise-dominant regime using two different feedback cooling schemes: the force feedback cooling and the parametric feedback cooling. Both quantum and classical calculations are performed, and an exact match is observed. We also explore the parameters that could possibly affect the cooling trend, where we find that the cooling limit for both cooling schemes strongly depends on the position measurement efficiency, and it poses good questions for researchers interested in achieving ground state cooling: what is the best measurement efficiency for a given measurement setup and what can be done to get a better measurement efficiency?

Ejector gas cooling. Phase 1. Final report, 1 April 1987-30 April 1988

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacCracken, C.D.; Silvetti, B.M.; Hrbek, R.

1988-11-01

Closed-circuit ejector cooling systems have never in the past achieved acceptable operating efficiencies in their vapor-compression cycle using standard refrigerants. Despite their long history, relative simplicity, quietness, rugged design, low maintenance and low cost, they could not compete with electric-motor-driven compressors. Phase I is an assessment of two immiscible fluids in an ejector cooling system with different latent heat capacity and molecular weights intended to require less heat in the boiler producing the propellant and taking more heat out in the evaporator cooling fluid. Actual tests corrected to standard conditions and neglecting thermal losses showed 0.5 closed-cycle thermal COP (excludingmore » stack losses), higher than ever previously achieved but below original expectations. Computer programs developed indicate higher COP values are attainable along with competitive first costs.« less

Implementation of a Legionella Ordinance for Multifamily Housing, Garland, Texas.

PubMed

Whitney, Ellen A; Blake, Sarah; Berkelman, Ruth L

The incidence of legionellosis has sharply increased in the United States as a result of contaminated water systems. Jurisdictions across the country are considering whether to develop and implement regulations to protect individuals against Legionnaires' disease with its associated high morbidity and mortality. This article sheds light on the implementation and effectiveness of a 2005 citywide Legionella testing mandate of multifamily housing cooling towers in Garland, Texas. This ordinance has been in place for more than 10 years and represents the first of its kind in the United States to mandate routine testing of cooling towers for Legionella in multifamily housing. We utilized a mix of both qualitative and quantitative methods to explore the development, adoption, and implementation of the ordinance. Phone interviews were conducted with individuals from the City of Garland Health Department and apartment managers. Quantitative data included public health surveillance data on legionellosis. Barriers and facilitators of implementation, number and percentage of cooling towers from multifamily housing units that tested positive for Legionella by year, and number of legionellosis cases by year in Garland, Texas. Study outcomes highlight key themes that facilitated the successful implementation of the Legionella testing mandate, including the importance of timing, leadership support, stakeholder engagement, and education and outreach. The number of contaminated cooling towers was reduced over time. Mandatory monitoring for legionella in a local jurisdiction may result in reduced risk of legionellosis from cooling towers through raising awareness and education of building owners and managers about the need to prevent, detect, and remediate legionella contamination in their building water systems. Garland, Texas, broke new ground in the United States in moving toward primary prevention of legionellosis. The ordinance may be useful both in serving to educate and increase awareness about the need for Legionella prevention and to monitor effectiveness of maintenance procedures.

On enhancing energy harvesting performance of the photovoltaic modules using an automatic cooling system and assessing its economic benefits of mitigating greenhouse effects on the environment

NASA Astrophysics Data System (ADS)

Wang, Jen-Cheng; Liao, Min-Sheng; Lee, Yeun-Chung; Liu, Cheng-Yue; Kuo, Kun-Chang; Chou, Cheng-Ying; Huang, Chen-Kang; Jiang, Joe-Air

2018-02-01

The performance of photovoltaic (PV) modules under outdoor operation is greatly affected by their location and environmental conditions. The temperature of a PV module gradually increases as it is exposed to solar irradiation, resulting in degradation of its electrical characteristics and power generation efficiency. This study adopts wireless sensor network (WSN) technology to develop an automatic water-cooling system for PV modules in order to improve their PV power generation efficiency. A temperature estimation method is developed to quickly and accurately estimate the PV module temperatures based on weather data provided from the WSN monitoring system. Further, an estimation method is also proposed for evaluation of the electrical characteristics and output power of the PV modules, which is performed remotely via a control platform. The automatic WSN-based water-cooling mechanism is designed to avoid the PV module temperature from reaching saturation. Equipping each PV module with the WSN-based cooling system, the ambient conditions are monitored automatically so that the temperature of the PV module is controlled by sprinkling water on the panel surface. The field-test experiment results show an increase in the energy harvested by the PV modules of approximately 17.75% when using the proposed WSN-based cooling system.

Infrared thermography based diagnosis of inter-turn fault and cooling system failure in three phase induction motor

NASA Astrophysics Data System (ADS)

Singh, Gurmeet; Naikan, V. N. A.

2017-12-01

Thermography has been widely used as a technique for anomaly detection in induction motors. International Electrical Testing Association (NETA) proposed guidelines for thermographic inspection of electrical systems and rotating equipment. These guidelines help in anomaly detection and estimating its severity. However, it focus only on location of hotspot rather than diagnosing the fault. This paper addresses two such faults i.e. inter-turn fault and failure of cooling system, where both results in increase of stator temperature. Present paper proposes two thermal profile indicators using thermal analysis of IRT images. These indicators are in compliance with NETA standard. These indicators help in correctly diagnosing inter-turn fault and failure of cooling system. The work has been experimentally validated for healthy and with seeded faults scenarios of induction motors.

Rapid Identification of a Cooling Tower-Associated Legionnaires' Disease Outbreak Supported by Polymerase Chain Reaction Testing of Environmental Samples, New York City, 2014-2015.

PubMed

Benowitz, Isaac; Fitzhenry, Robert; Boyd, Christopher; Dickinson, Michelle; Levy, Michael; Lin, Ying; Nazarian, Elizabeth; Ostrowsky, Belinda; Passaretti, Teresa; Rakeman, Jennifer; Saylors, Amy; Shamoonian, Elena; Smith, Terry-Ann; Balter, Sharon

2018-04-01

We investigated an outbreak of eight Legionnaires' disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings.

Preburner of Staged Combustion Rocket Engine

NASA Technical Reports Server (NTRS)

Yost, M. C.

1978-01-01

A regeneratively cooled LOX/hydrogen staged combustion assembly system with a 400:1 expansion area ratio nozzle utilizing an 89,000 Newton (20,000 pound) thrust regeneratively cooled thrust chamber and 175:1 tubular nozzle was analyzed, assembled, and tested. The components for this assembly include two spark/torch oxygen-hydrogen igniters, two servo-controlled LOX valves, a preburner injector, a preburner combustor, a main propellant injector, a regeneratively cooled combustion chamber, a regeneratively cooled tubular nozzle with an expansion area ratio of 175:1, an uncooled heavy-wall steel nozzle with an expansion area ratio of 400:1, and interconnecting ducting. The analytical effort was performed to optimize the thermal and structural characteristics of each of the new components and the ducting, and to reverify the capabilities of the previously fabricated components. The testing effort provided a demonstration of the preburner/combustor chamber operation, chamber combustion efficiency and stability, and chamber and nozzle heat transfer.

Investigation of light source and scattering medium related to vapor-screen flow visualization in a supersonic wind tunnel

NASA Technical Reports Server (NTRS)

Snow, W. L.; Morris, O. A.

1984-01-01

Methods for increasing the radiant in light sheets used for vapor screen set-ups were investigated. Both high-pressure mercury arc lamps and lasers were considered. Pulsed operation of the air-cooled 1-kW lamps increased the light output but decreased reliability. An ellipsoidal mirror improved the output of the air-cooled lamps by concentrating the light but increased the complexity of the housing. Water-cooled-4-kW lamps coupled with high-aperture Fresnel lenses provided reasonable improvements over the air-cooled lamps. Fanned laser beams measurements of scattered light versus dew point made in conjunction with successful attempts to control the fluid injection. A number of smoke generators are described and test results comparing smoke and vapor screens are shown. Finally, one test included a periscope system to relay the image to a camera outside the flow.

14 CFR 29.1043 - Cooling tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Cooling tests. 29.1043 Section 29.1043... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Cooling § 29.1043 Cooling tests. (a) General. For the tests prescribed in § 29.1041(c), the following apply: (1) If the tests are conducted under conditions...

14 CFR 29.1043 - Cooling tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Cooling tests. 29.1043 Section 29.1043... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Cooling § 29.1043 Cooling tests. (a) General. For the tests prescribed in § 29.1041(c), the following apply: (1) If the tests are conducted under conditions...

14 CFR 27.1043 - Cooling tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Cooling tests. 27.1043 Section 27.1043... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Cooling § 27.1043 Cooling tests. (a) General. For the tests prescribed in § 27.1041(b), the following apply: (1) If the tests are conducted under conditions deviating...

14 CFR 27.1043 - Cooling tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 27.1043 Section 27.1043... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Cooling § 27.1043 Cooling tests. (a) General. For the tests prescribed in § 27.1041(b), the following apply: (1) If the tests are conducted under conditions deviating...

14 CFR 29.1043 - Cooling tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 29.1043 Section 29.1043... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Cooling § 29.1043 Cooling tests. (a) General. For the tests prescribed in § 29.1041(c), the following apply: (1) If the tests are conducted under conditions...

14 CFR 27.1043 - Cooling tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Cooling tests. 27.1043 Section 27.1043... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Cooling § 27.1043 Cooling tests. (a) General. For the tests prescribed in § 27.1041(b), the following apply: (1) If the tests are conducted under conditions deviating...

Legionella species colonization in cooling towers: risk factors and assessment of control measures.

PubMed

Mouchtouri, Varvara A; Goutziana, Georgia; Kremastinou, Jenny; Hadjichristodoulou, Christos

2010-02-01

Cooling towers can be colonized by Legionella spp, and inhalation of aerosols generated by their operation may cause Legionnaires' disease in susceptible hosts. Environmental investigations of Legionnaires' disease outbreaks linked with cooling towers have revealed poorly maintained systems, lack of control measures, and failure of system equipment. The purpose of this study was to identify Legionella-contaminated cooling towers, identify risk factors for contamination, and assess the effectiveness of control measures. A total of 96 cooling towers of public buildings were registered and inspected, and 130 samples were collected and microbiologically tested. Microbiological test results were associated with characteristics of cooling towers, water samples, inspection results, and maintenance practices. Of the total 96 cooling towers examined, 47 (48.9%) were colonized by Legionella spp, and 22 (22.9%) required remedial action. A total of 65 samples (50.0%) were positive (> or = 500 cfu L(-1)), and 30 (23%) were heavily contaminated (> or = 10(4) cfu L(-1)). Of the 69 isolates identified, 55 strains (79.7.%) were L pneumophila. Legionella colonization was positively associated with the absence of training on Legionella control (relative risk [RR] = 1.66; P = .02), absence of regular Legionella testing (RR = 2.07: P = .002), absence of sunlight protection (RR = 1.63: P = .02), with samples in which the free residual chlorine level in the water sample was < 0.5 mg/L (RR = 2.23; P = .01), and with total plate count (P =.001). Colonization was negatively associated with chemical disinfection (RR = 0.2; P = .0003) and with the presence of a risk assessment and management plan (RR = 0.12; P = .0005). A statistically significant higher age (P =.01) was found in legionellae-positive cooling towers (median, 17 years; interquartile range [IQR] =5.0 to 26.0 years) compared with noncolonized cooling towers (median age, 6 years; IQR =1.0 to 13.5 years). After the 22 legionellae-positive cooling towers were disinfected with chlorine, 2 (9%) of them remained positive for Legionella spp with a concentration > or = 1000 cfu L(-1). Cooling towers can be heavily colonized by Legionella spp and thus present a potential risk for infection. This study demonstrates the importance of a risk assessment and management plan. Water chlorination effectively reduces legionellae contamination. Proper training of cooling tower operators is paramount. Copyright 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Temperature distribution of a hot water storage tank in a simulated solar heating and cooling system

NASA Technical Reports Server (NTRS)

Namkoong, D.

1976-01-01

A 2,300-liter hot water storage tank was studied under conditions simulating a solar heating and cooling system. The initial condition of the tank, ranging from 37 C at the bottom to 94 C at the top, represented a condition midway through the start-up period of the system. During the five-day test period, the water in the tank gradually rose in temperature but in a manner that diminished its temperature stratification. Stratification was found not to be an important factor in the operation of the particular solar system studied.

Development of a Cool Propellant for the 3 in./50 Caliber Gun. Development of a Cool Propellant for the 3 in./70 Caliber Gun. Development of Ignition Systems for the Cool Propellant Charges. Ballistic Test of Cool Propellants EX-6735, EX-6721 and IHPB-S-83C

DTIC Science & Technology

1951-06-09

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380 kW synchronous machine with HTS rotor windings--development at Siemens and first test results

NASA Astrophysics Data System (ADS)

Nick, W.; Nerowski, G.; Neumüller, H.-W.; Frank, M.; van Hasselt, P.; Frauenhofer, J.; Steinmeyer, F.

2002-08-01

Applying HTS conductors in the rotor of synchronous machines allows the design of future motors or generators that are lighter, more compact and feature an improved coefficient of performance. To address these goals a project collaboration was installed within Siemens, including Automation & Drives, Large Drives as a leading supplier of electrical machines, Corporate Technology as a competence center for superconducting technology, and other partners. The main task of the project was to demonstrate the feasibility of basic concepts. The rotor was built from racetrack coils of Bi-2223 HTS tape conductor, these were assembled on a core and fixed by a bandage of glass-fibre composite. Rotor coil cooling is performed by thermal conduction, one end of the motor shaft is hollow to give access for the cooling system. Two cooling systems were designed and operated successfully: firstly an open circuit using cold gaseous helium from a storage vessel, but also a closed circuit system based on a cryogenerator. To take advantage of the increased rotor induction levels the stator winding was designed as an air gap winding. This was manufactured and fitted in a standard motor housing. After assembling of the whole system in a test facility with a DC machine load experiments have been started to prove the validity of our design, including operation with both cooling systems and driving the stator from the grid as well as by a power inverter.

Method for thermoelectric cooler utilization using manufacturer's technical information

NASA Astrophysics Data System (ADS)

Ajiwiguna, Tri Ayodha; Nugroho, Rio; Ismardi, Abrar

2018-03-01

Thermoelectric cooler (TEC) module has been widely used for many applications. In this study, a procedure to use TEC module for specific requirement is developed based on manufacturer's technical data. For study case, the cooling system using TEC module is designed and tested to maintain 6.6 liter of water at 24 °C while surrounding temperature is 26 °C. First, cooling load estimation is performed empirically by observing the temperature change when cold water is inside the container. Second, the working temperature on hot side and cold side of TEC are determined. Third, the parameters of Seebeck coefficient, thermal resistance and electrical resistance are predicted by using information from the manufacturer. Fourth, the operating current is determined by the assumption the voltage across the TEC is 12V. Fifth, cooling capacity of TEC module is calculated by using energy balance equation of TEC. Sixth, the cooling load and cooling capacity are compared to determine the number of TEC module needed. The result of these calculations showed that one TEC module is enough for cooling system since the cooling load is 17.5 W while the cooling capacity is 18.87 W. From the experimental result, the set point temperature was achieved using one TEC module as predicted in calculations steps.

Cryogenically cooled low-noise amplifier for radio-astronomical observations and centimeter-wave deep-space communications systems

NASA Astrophysics Data System (ADS)

Vdovin, V. F.; Grachev, V. G.; Dryagin, S. Yu.; Eliseev, A. I.; Kamaletdinov, R. K.; Korotaev, D. V.; Lesnov, I. V.; Mansfeld, M. A.; Pevzner, E. L.; Perminov, V. G.; Pilipenko, A. M.; Sapozhnikov, B. D.; Saurin, V. P.

2016-01-01

We report a design solution for a highly reliable, low-noise and extremely efficient cryogenically cooled transmit/receive unit for a large antenna system meant for radio-astronomical observations and deep-space communications in the X band. We describe our design solution and the results of a series of laboratory and antenna tests carried out in order to investigate the properties of the cryogenically cooled low-noise amplifier developed. The transmit/receive unit designed for deep-space communications (Mars missions, radio observatories located at Lagrangian point L2, etc.) was used in practice for communication with live satellites including "Radioastron" observatory, which moves in a highly elliptical orbit.

Evaporator Development for an Evaporative Heat Pipe System

NASA Technical Reports Server (NTRS)

Peters, Leigh C.

2004-01-01

As fossil fuel resources continue to deplete, research for alternate power sources continues to develop. One of these alternate technologies is fuel cells. They are a practical fuel source able to provide significant amounts of power for applications from laptops to automobiles and their only byproduct is water. However, although this technology is over a century old and NASA has been working with it since the early 1960 s there is still room for improvement. The research I am involved in at NASA's Glenn Research Center is focusing on what is called a regenerative fuel cell system. The unique characteristic of this type of system is that it used an outside power source to create electrolysis of the water it produces and it then reuses the hydrogen and oxygen to continue producing power. The advantage of this type of system is that, for example, on space missions it can use solar power to recharge its gas supplies between periods when the object being orbited blocks out the sun. This particular system however is far from completion. This is because of the many components that are required to make up a fuel cell that need to be tested individually. The specific part of the system that is being worked on this summer of 2004 is the cooling system. The fuel cell stack, that is the part that actually creates the power, also produces a lot of heat. When not properly cooled, it has been known to cause fires which, needless to say are not conducive to the type of power that is trying to be created. In order to cool the fuel cell stack in this system we are developing a heat pipe cooling system. One of the main components of a heat pipe cooling system is what is known as the evaporator, and that is what happens to be the part of the system we are developing this summer. In most heat pipe systems the evaporator is a tube in which the working fluid is cooled and then re-circulated through the system to absorb more heat energy from the fuel cell stack. For this system, instead of a tube, the evaporator is made up of a stack-up of screen material and absorbent membranes inside a stainless steel shell and held together by a film adhesive and epoxy. There is an initial design for this flat plate evaporator, however is has not yet been made. The components of the stack-up are known, so all testing is focused on how it will all go together. This includes finding an appropriate epoxy to make the evaporator conductive all the way through and finding a way to hold the required tight tolerances as the stainless steel outer shell is put together. By doing the tests on smaller samples of the stack-ups and then testing the fill size component, the final flat plate evaporator will reach its final design so that research can continue on other parts of the regenerative fue1 cell system, and another step in the improvement of fue1 cell technology can be made.

KSC-02pd0032

NASA Image and Video Library

2002-01-17

KENNEDY SPACE CENTER, FLA. -- In the Vertical Processing Facility, workers help guide the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System into an protective enclosure on a payload carrier. NICMOS II is part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. It is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002

Assessment of Alphamagnetic Spectrometer (AMS) Upper Experiment Structural Configuration Shielding Effectiveness Associated with Change from Cryo-Cooled Magnet to Permanent Magnet

NASA Technical Reports Server (NTRS)

Scully, Robert

2012-01-01

In the spring of 2010, the Alpha Magnetic Spectrometer 2 (AMS-02) underwent a series of system level electromagnetic interference control measurements, followed by thermal vacuum testing. Shortly after completion of the thermal vacuum testing, the project decided to remove the cryogenically cooled superconducting magnet, and replace it with the original permanent magnet design employed in the earlier AMS- 01 assembly. Doing so necessitated several structural changes, as well as removal or modification of numerous electronic and thermal control devices and systems. At this stage, the project was rapidly approaching key milestone dates for hardware completion and delivery for launch, and had little time for additional testing or assessment of any impact to the electromagnetic signature of the AMS-02. Therefore, an analytical assessment of the radiated emissions behavioural changes associated with the system changes was requested.

Evaluation of a teflon based ultraviolet light system on the disinfection of water in a textile air washer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, J.E.; Whisnant, R.B.

The report provides an in-depth evaluation of an ultraviolet (UV) disinfection unit as applied to the treatment of cooling water in a textile air washer system. The UV unit tests used a teflon tube to transport the aquatic phase. The unit reduced microbial populations and maintained an average level of 10,000 Colony formed unites/mL for the 6-month testing period, without the addition of biocides. No cleaning or other maintenance was required of the wetted surfaces during the testing period. Slime deposits observed on walls of the air washer during chemical treatment were also eliminated. The UV unit can be utilizedmore » on both cooling towers and air washers without extensive installation.« less

Webb's MIRI Shield Dropping in on Dropping Temperatures

NASA Image and Video Library

2013-12-04

Goddard Technicians Tony Kiem (left) and George Mooney (right) guide the craned structure holding the Webb telescope's Mid-Infrared Instrument or MIRI Shield Environmental Test Unit into place in a cryogenic (cooling) test chamber. This shield will be used to simulate the MIRI instrument during prelaunch testing to verify that the MIRI cooling system will function properly in space. Goddard Safety Engineer Richard Bowlan watches from above. Image Credit: NASA/Chris Gunn NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

A Gas-Cooled-Reactor Closed-Brayton-Cycle Demonstration with Nuclear Heating

NASA Astrophysics Data System (ADS)

Lipinski, Ronald J.; Wright, Steven A.; Dorsey, Daniel J.; Peters, Curtis D.; Brown, Nicholas; Williamson, Joshua; Jablonski, Jennifer

2005-02-01

A gas-cooled reactor may be coupled directly to turbomachinery to form a closed-Brayton-cycle (CBC) system in which the CBC working fluid serves as the reactor coolant. Such a system has the potential to be a very simple and robust space-reactor power system. Gas-cooled reactors have been built and operated in the past, but very few have been coupled directly to the turbomachinery in this fashion. In this paper we describe the option for testing such a system with a small reactor and turbomachinery at Sandia National Laboratories. Sandia currently operates the Annular Core Research Reactor (ACRR) at steady-state powers up to 4 MW and has an adjacent facility with heavy shielding in which another reactor recently operated. Sandia also has a closed-Brayton-Cycle test bed with a converted commercial turbomachinery unit that is rated for up to 30 kWe of power. It is proposed to construct a small experimental gas-cooled reactor core and attach this via ducting to the CBC turbomachinery for cooling and electricity production. Calculations suggest that such a unit could produce about 20 kWe, which would be a good power level for initial surface power units on the Moon or Mars. The intent of this experiment is to demonstrate the stable start-up and operation of such a system. Of particular interest is the effect of a negative temperature power coefficient as the initially cold Brayton gas passes through the core during startup or power changes. Sandia's dynamic model for such a system would be compared with the performance data. This paper describes the neutronics, heat transfer, and cycle dynamics of this proposed system. Safety and radiation issues are presented. The views expressed in this document are those of the author and do not necessarily reflect agreement by the government.

Control of mineral scale deposition in cooling systems using secondary-treated municipal wastewater.

PubMed

Li, Heng; Hsieh, Ming-Kai; Chien, Shih-Hsiang; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

2011-01-01

Secondary-treated municipal wastewater (MWW) is a promising alternative to freshwater as power plant cooling system makeup water, especially in arid regions. A prominent challenge for the successful use of MWW for cooling is potentially severe mineral deposition (scaling) on pipe surfaces. In this study, theoretical, laboratory, and field work was conducted to evaluate the mineral deposition potential of MWW and its deposition control strategies under conditions relevant to power plant cooling systems. Polymaleic acid (PMA) was found to effectively reduce scale formation when the makeup water was concentrated four times in a recirculating cooling system. It was the most effective deposition inhibitor of those studied when applied at 10 mg/L dosing level in a synthetic MWW. However, the deposition inhibition by PMA was compromised by free chlorine added for biogrowth control. Ammonia present in the wastewater suppressed the reaction of the free chlorine with PMA through the formation of chloramines. Monochloramine, an alternative to free chlorine, was found to be less reactive with PMA than free chlorine. In pilot tests, scaling control was more challenging due to the occurrence of biofouling even with effective control of suspended bacteria. Phosphorous-based corrosion inhibitors are not appropriate due to their significant loss through precipitation reactions with calcium. Chemical equilibrium modeling helped with interpretation of mineral precipitation behavior but must be used with caution for recirculating cooling systems, especially with use of MWW, where kinetic limitations and complex water chemistries often prevail. Copyright © 2010 Elsevier Ltd. All rights reserved.

Design of thermal protection system for 8 foot HTST combustor

NASA Technical Reports Server (NTRS)

Moskowitz, S.

1973-01-01

The combustor in the 8-foot high temperature structures tunnel at the NASA-Langley Research Center has encountered cracking over a period of 50-250 tunnel tests within a limited range of the required operating envelope. A program was conducted which analyzed the failed combustor liner hardware and determined that the mechanism of failure was vibratory fatigue. A vibration damper system using wave springs located axially between the liner T-bar and the liner support was designed as an intermediate solution to extend the life of the current two-pass regenerative air-cooled liner. The effects of liner wall thickness, cooling air passage height, stiffener ring geometry, reflective coatings, and liner material selection were investigated for these designs. Preliminary layout design arrangements including the external water-cooling system requirements, weight estimates, installation requirements and preliminary estimates of manufacturing costs were prepared for the most promissing configurations. A state-of-the-art review of thermal barrier coatings and an evaluation of reflective coatings for the gasside surface of air-cooled liners are included.

Trapped ultracold molecular ions: candidates for an optical molecular clock for a fundamental physics mission in space

NASA Astrophysics Data System (ADS)

Roth, B.; Koelemeij, J.; Daerr, H.; Ernsting, I.; Jorgensen, S.; Okhapkin, M.; Wicht, A.; Nevsky, A.; Schiller, S.

2017-11-01

Narrow ro-vibrational transitions in ultracold molecules are excellent candidates for frequency references in the near-IR to visible spectral domain and interesting systems for fundamental tests of physics, in particular for a satellite test of the gravitational redshift of clocks. We have performed laser spectroscopy of several ro-vibrational overtone transitions υ = 0 → υ = 4 in HD+ ions at around 1.4 μm. 1+1 REMPD was used as a detection method, followed by measurement of the number of remaining molecules. The molecular ions were stored in a linear radiofrequency trap and cooled to millikelvin temperatures, by sympathetic cooling using laser-cooled Be+ ions simultaneously stored in the same trap.

Demonstration of Super Cooled Ice as a Phase Change Material Heat Sink for Portable Life Support Systems

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Bue, Grant C.

2009-01-01

A phase change material (PCM) heat sink using super cooled ice as a nontoxic, nonflammable PCM is being developed. The latent heat of fusion for water is approximately 70% larger than most paraffin waxes, which can provide significant mass savings. Further mass reduction is accomplished by super cooling the ice significantly below its freezing temperature for additional sensible heat storage. Expansion and contraction of the water as it freezes and melts is accommodated with the use of flexible bag and foam materials. A demonstrator unit has been designed, built, and tested to demonstrate proof of concept. Both testing and modeling results are presented along with recommendations for further development of this technology.

An experimental investigation of the aerodynamics and cooling of a horizontally-opposed air-cooled aircraft engine installation

NASA Technical Reports Server (NTRS)

Miley, S. J.; Cross, E. J., Jr.; Owens, J. K.; Lawrence, D. L.

1981-01-01

A flight-test based research program was performed to investigate the aerodynamics and cooling of a horizontally-opposed engine installation. Specific areas investigated were the internal aerodynamics and cooling mechanics of the installation, inlet aerodynamics, and exit aerodynamics. The applicable theory and current state of the art are discussed for each area. Flight-test and ground-test techniques for the development of the cooling installation and the solution of cooling problems are presented. The results show that much of the internal aerodynamics and cooling technology developed for radial engines are applicable to horizontally opposed engines. Correlation is established between engine manufacturer's cooling design data and flight measurements of the particular installation. Also, a flight-test method for the development of cooling requirements in terms of easily measurable parameters is presented. The impact of inlet and exit design on cooling and cooling drag is shown to be of major significance.

Study on energy saving effect of IHX on vehicle air conditioning system

NASA Astrophysics Data System (ADS)

Li, Huguang; Tong, Lin; Xu, Ming; Wei, Wangrui; Zhao, Meng; Wang, Long

2018-02-01

In this paper, the performance of Internal Heat Exchanger (IHX) air conditioning system for R134a is investigated in bench test and vehicle test. Comparison for cooling capacity and energy consumption between IHX air conditioning system and traditional tube air conditioning system are conducted. The suction temperature and discharge temperature of compressor is also recorded. The results show that IHX air conditioning system has higher cooling capacity, the vent temperature decrease 2.3 °C in idle condition. But the suction temperature and discharge temperature of compressor increase 10°C. IHX air conditioning system has lower energy consumption than traditional tube air conditioning system. Under the experimental conditions in this paper, the application of IHX can significantly reduce the energy consumption of air conditioning system. At 25°C of environment temperature, AC system energy consumption decrease 14%, compressor energy consumption decrease 16%. At 37°C of environment temperature, AC system energy consumption decrease 16%, compressor energy consumption decrease 13%.

Effectiveness-weighted control method for a cooling system

DOEpatents

Campbell, Levi A.; Chu, Richard C.; David, Milnes P.; Ellsworth Jr., Michael J.; Iyengar, Madhusudan K.; Schmidt, Roger R.; Simons, Robert E.

2015-12-15

Energy efficient control of cooling system cooling of an electronic system is provided based, in part, on weighted cooling effectiveness of the components. The control includes automatically determining speed control settings for multiple adjustable cooling components of the cooling system. The automatically determining is based, at least in part, on weighted cooling effectiveness of the components of the cooling system, and the determining operates to limit power consumption of at least the cooling system, while ensuring that a target temperature associated with at least one of the cooling system or the electronic system is within a desired range by provisioning, based on the weighted cooling effectiveness, a desired target temperature change among the multiple adjustable cooling components of the cooling system. The provisioning includes provisioning applied power to the multiple adjustable cooling components via, at least in part, the determined control settings.

Effectiveness-weighted control of cooling system components

DOEpatents

Campbell, Levi A.; Chu, Richard C.; David, Milnes P.; Ellsworth Jr., Michael J.; Iyengar, Madhusudan K.; Schmidt, Roger R.; Simmons, Robert E.

2015-12-22

Energy efficient control of cooling system cooling of an electronic system is provided based, in part, on weighted cooling effectiveness of the components. The control includes automatically determining speed control settings for multiple adjustable cooling components of the cooling system. The automatically determining is based, at least in part, on weighted cooling effectiveness of the components of the cooling system, and the determining operates to limit power consumption of at least the cooling system, while ensuring that a target temperature associated with at least one of the cooling system or the electronic system is within a desired range by provisioning, based on the weighted cooling effectiveness, a desired target temperature change among the multiple adjustable cooling components of the cooling system. The provisioning includes provisioning applied power to the multiple adjustable cooling components via, at least in part, the determined control settings.

Thermal/Fluid Analysis of a Composite Heat Exchanger for Use on the RLV Rocket Engine

NASA Technical Reports Server (NTRS)

Nguyen, Dalton

2002-01-01

As part of efforts to design a regeneratively cooled composite nozzle ramp for use on the reusable vehicle (RLV) rocket engine, an C-SiC composites heat exchanger concept was proposed for thermal performance evaluation. To test the feasibility of the concept, sample heat exchanger panels were made to fit the Glenn Research Center's cell 22 for testing. Operation of the heat exchanger was demonstrated in a combustion environment with high heat fluxes similar to the RLV Aerospike Ramp. Test measurements were reviewed and found to be valuable for the on going fluid and thermal analysis of the actual RLV composite ramp. Since the cooling fluid for the heat exchanger is water while the RLV Ramp cooling fluid is LH2, fluid and thermal models were constructed to correlate to the specific test set-up. The knowledge gained from this work will be helpful for analyzing the thermal response of the actual RLV Composite Ramp. The coolant thermal properties for the models are taken from test data. The heat exchanger's cooling performance was analyzed using the Generalized Fluid System Simulation Program (GFSSP). Temperatures of the heat exchanger's structure were predicted in finite element models using Patran and Sinda. Results from the analytical models and the tests show that RSC's heat exchanger satisfied the combustion environments in a series of 16 tests.

Thermal/Fluid Analysis of a Composite Heat Exchanger for Use on the RLV Rocket Engine

NASA Technical Reports Server (NTRS)

Nguyen, Dalton; Turner, Larry D. (Technical Monitor)

2001-01-01

As part of efforts to design a regeneratively cooled composite nozzle ramp for use on the reusable vehicle (RLV) rocket engine, a C-SiC composite heat exchanger concept was proposed for thermal performance evaluation. To test the feasibility of the concept, sample heat exchanger panels were made to fit the Glenn Research Center's cell 22 for testing. Operation of the heat exchanger was demonstrated in a combustion environment with high heat fluxes similar to the RLV Aerospike Ramp. Test measurements were reviewed and found to be valuable for the on-going fluid and thermal analysis of the actual RLV composite ramp. Since the cooling fluid for the heat exchanger is water while the RLV Ramp cooling fluid is LH2, fluid and therma models were constructed to correlate to the specific test set-up. The knowledge gained from this work will be helpful for analyzing the thermal response of the actual RLV Composite Ramp. The coolant thermal properties for the models are taken from test data. The heat exchanger's cooling performance was analyzed using the Generalized Fluid System Simulation Program (GFSSP). Temperatures of the heat exchanger's structure were predicted in finite element models using Patran and Sinda. Results from the analytical models and the tests show that RSC's heat exchanger satisfied the combustion environments in a series of 16 tests.

System integration of marketable subsystems. [for residential solar heating and cooling

NASA Technical Reports Server (NTRS)

1979-01-01

Progress is reported in the following areas: systems integration of marketable subsystems; development, design, and building of site data acquisition subsystems; development and operation of the central data processing system; operation of the MSFC Solar Test Facility; and systems analysis.

SOFI/Substrate integrity testing for cryogenic propellant tanks at extreme thermal gradient conditions

NASA Astrophysics Data System (ADS)

Haynes, M.; Fabian, P.

2015-12-01

Liquid propellant tank insulation for space flight requires low weight as well as high insulation factors. Use of Spray-On Foam Insulation (SOFI) is an accepted, cost effective technique for insulating a single wall cryogenic propellant tank and has been used extensively throughout the aerospace industry. Determining the bond integrity of the SOFI to the metallic substrate as well as its ability to withstand the in-service strains, both mechanical and thermal, is critical to the longevity of the insulation. This determination has previously been performed using highly volatile, explosive cryogens, which increases the test costs enormously, as well as greatly increasing the risk to both equipment and personnel. CTD has developed a new test system, based on a previous NASA test that simulates the mechanical and thermal strains associated with filling a large fuel tank with a cryogen. The test enables a relatively small SOFI/substrate sample to be monitored for any deformations, delaminations, or disjunctures during the cooling and mechanical straining process of the substrate, and enables the concurrent application of thermal and physical strains to two specimens at the same time. The thermal strains are applied by cooling the substrate to the desired cryogen temperature (from 4 K to 250 K) while maintaining the outside surface of the SOFI foam at ambient conditions. Multiple temperature monitoring points are exercised to ensure even cooling across the substrate, while at the same time, surface temperatures of the SOFI can be monitored to determine the heat flow. The system also allows for direct measurement of the strains in the substrate during the test. The test system as well as test data from testing at 20 K, for liquid Hydrogen simulation, will be discussed.

Analysis and test of insulated components for rotary engine

NASA Technical Reports Server (NTRS)

Badgley, Patrick R.; Doup, Douglas; Kamo, Roy

1989-01-01

The direct-injection stratified-charge (DISC) rotary engine, while attractive for aviation applications due to its light weight, multifuel capability, and potentially low fuel consumption, has until now required a bulky and heavy liquid-cooling system. NASA-Lewis has undertaken the development of a cooling system-obviating, thermodynamically superior adiabatic rotary engine employing state-of-the-art thermal barrier coatings to thermally insulate engine components. The thermal barrier coating material for the cast aluminum, stainless steel, and ductile cast iron components was plasma-sprayed zirconia. DISC engine tests indicate effective thermal barrier-based heat loss reduction, but call for superior coefficient-of-thermal-expansion matching of materials and better tribological properties in the coatings used.

Urine sampling and collection system optimization and testing

NASA Technical Reports Server (NTRS)

Fogal, G. L.; Geating, J. A.; Koesterer, M. G.

1975-01-01

A Urine Sampling and Collection System (USCS) engineering model was developed to provide for the automatic collection, volume sensing and sampling of urine from each micturition. The purpose of the engineering model was to demonstrate verification of the system concept. The objective of the optimization and testing program was to update the engineering model, to provide additional performance features and to conduct system testing to determine operational problems. Optimization tasks were defined as modifications to minimize system fluid residual and addition of thermoelectric cooling.

The control system of a 2kW@20K helium refrigerator

NASA Astrophysics Data System (ADS)

Pan, W.; Wu, J. H.; Li, Qing; Liu, L. Q.; Li, Qiang

2017-12-01

The automatic control of a helium refrigerator includes three aspects, that is, one-button start and stop control, safety protection control, and cooling capacity control. The 2kW@20K helium refrigerator’s control system uses the SIEMENS PLC S7-300 and its related programming and configuration software Step7 and the industrial monitoring software WinCC, to realize the dynamic control of its process, the real-time monitoring of its data, the safety interlock control, and the optimal control of its cooling capacity. At first, this paper describes the control architecture of the whole system in detail, including communication configuration and equipment introduction; and then introduces the sequence control strategy of the dynamic processes, including the start and stop control mode of the machine and the safety interlock control strategy of the machine; finally tells the precise control strategy of the machine’s cooling capacity. Eventually, the whole system achieves the target of one-button starting and stopping, automatic fault protection and stable running to the target cooling capacity, and help finished the cold helium pressurization test of aerospace products.

Solar thermoelectric cooling using closed loop heat exchangers with macro channels

NASA Astrophysics Data System (ADS)

Atta, Raghied M.

2017-07-01

In this paper we describe the design, analysis and experimental study of an advanced coolant air conditioning system which cools or warms airflow using thermoelectric (TE) devices powered by solar cells. Both faces of the TE devices are directly connected to closed-loop highly efficient channels plates with macro scale channels and liquid-to-air heat exchangers. The hot side of the system consists of a pump that moves a coolant through the hot face of the TE modules, a radiator that drives heat away into the air, and a fan that transfer the heat over the radiator by forced convection. The cold side of the system consists also of a pump that moves coolant through the cold face of the TE modules, a radiator that drives cold away into the air, and a fan that blows cold air off the radiator. The system was integrated with solar panels, tested and its thermal performance was assessed. The experimental results verify the possibility of heating or cooling air using TE modules with a relatively high coefficient of performance (COP). The system was able to cool a closed space of 30 m3 by 14 °C below ambient within 90 min. The maximum COP of the whole system was 0.72 when the TE modules were running at 11.2 Å and 12 V. This improvement in the system COP over the air cooled heat sink is due to the improvement of the system heat exchange by means of channels plates.

Demand Shifting with Thermal Mass in Large Commercial Buildings in a California Hot Climate Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Peng; Yin, Rongxin; Brown, Carrie

2009-06-01

The potential for using building thermal mass for load shifting and peak energy demand reduction has been demonstrated in a number of simulation, laboratory, and field studies. Previous Lawrence Berkeley National Laboratory research has demonstrated that the approach is very effective in cool and moderately warm climate conditions (California Climate Zones 2-4). However, this method had not been tested in hotter climate zones. This project studied the potential of pre-cooling the building early in the morning and increasing temperature setpoints during peak hours to reduce cooling-related demand in two typical office buildings in hotter California climates ? one in Visaliamore » (CEC Climate Zone 13) and the other in San Bernardino (CEC Climate Zone 10). The conclusion of the work to date is that pre-cooling in hotter climates has similar potential to that seen previously in cool and moderate climates. All other factors being equal, results to date indicate that pre-cooling increases the depth (kW) and duration (kWh) of the possible demand shed of a given building. The effectiveness of night pre-cooling in typical office building under hot weather conditions is very limited. However, night pre-cooling is helpful for office buildings with an undersized HVAC system. Further work is required to duplicate the tests in other typical buildings and in other hot climate zones and prove that pre-cooling is truly effective.« less

Progress Towards the Development of a Long-Lived Venus Lander Duplex System

NASA Technical Reports Server (NTRS)

Dyson, Roger W.; Bruder, Geoffrey A.

2010-01-01

NASA has begun the development of a combined Stirling cycle power and cooling system (duplex) to enable the long-lived surface exploration of Venus and other harsh environments in the solar system. The duplex system will operate from the heat provided by decaying radioisotope plutonium-238 or its substitute. Since the surface of Venus has a thick, hot, and corrosive atmosphere, it is a challenging proposition to maintain sensitive lander electronics under survivable conditions. This development effort requires the integration of: a radioisotope or fission heat source; heat pipes; high-temperature, corrosion-resistant material; multistage cooling; a novel free-displacer Stirling convertor for the lander; and a minimal vibration thermoacoustic Stirling convertor for the seismometer. The first year effort includes conceptual system design and control studies, materials development, and prototype hardware testing. A summary of these findings and test results is presented in this report.

Progress Towards the Development of a Long-Lived Venus Lander Duplex System

NASA Technical Reports Server (NTRS)

Dyson, Rodger, W.; Bruder, Geoffrey A.

2011-01-01

NASA has begun the development of a combined Stirling cycle power and cooling system (duplex) to enable the long-lived surface exploration of Venus and other harsh environments in the solar system. The duplex system will operate from the heat provided by decaying radioisotope plutonium-238 or its substitute. Since the surface of Venus has a thick, hot, and corrosive atmosphere, it is a challenging proposition to maintain sensitive lander electronics under survivable conditions. This development effort requires the integration of: a radioisotope or fission heat source; heat pipes; high-temperature, corrosion-resistant material; multistage cooling; a novel free-displacer Stirling convertor for the lander; and a minimal vibration thermoacoustic Stirling convertor for the seismometer. The first year effort includes conceptual system design and control studies, materials development, and prototype hardware testing. A summary of these findings and test results is presented in this report.

14 CFR 25.1043 - Cooling tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Cooling tests. 25.1043 Section 25.1043... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Cooling § 25.1043 Cooling tests. (a) General. Compliance with § 25.1041 must be shown by tests, under critical ground, water, and flight operating conditions...

14 CFR 25.1043 - Cooling tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 25.1043 Section 25.1043... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Cooling § 25.1043 Cooling tests. (a) General. Compliance with § 25.1041 must be shown by tests, under critical ground, water, and flight operating conditions...

14 CFR 25.1043 - Cooling tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Cooling tests. 25.1043 Section 25.1043... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Cooling § 25.1043 Cooling tests. (a) General. Compliance with § 25.1041 must be shown by tests, under critical ground, water, and flight operating conditions...

Tritium processing for the European test blanket systems: current status of the design and development strategy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ricapito, I.; Calderoni, P.; Poitevin, Y.

2015-03-15

Tritium processing technologies of the two European Test Blanket Systems (TBS), HCLL (Helium Cooled Lithium Lead) and HCPB (Helium Cooled Pebble Bed), play an essential role in meeting the main objectives of the TBS experimental campaign in ITER. The compliancy with the ITER interface requirements, in terms of space availability, service fluids, limits on tritium release, constraints on maintenance, is driving the design of the TBS tritium processing systems. Other requirements come from the characteristics of the relevant test blanket module and the scientific programme that has to be developed and implemented. This paper identifies the main requirements for themore » design of the TBS tritium systems and equipment and, at the same time, provides an updated overview on the current design status, mainly focusing onto the tritium extractor from Pb-16Li and TBS tritium accountancy. Considerations are also given on the possible extrapolation to DEMO breeding blanket. (authors)« less

Regeneratively Cooled Liquid Oxygen/Methane Technology Development Between NASA MSFC and PWR

NASA Technical Reports Server (NTRS)

Robinson, Joel W.; Greene, Christopher B.; Stout, Jeffrey B.

2012-01-01

The National Aeronautics & Space Administration (NASA) has identified Liquid Oxygen (LOX)/Liquid Methane (LCH4) as a potential propellant combination for future space vehicles based upon exploration studies. The technology is estimated to have higher performance and lower overall systems mass compared to existing hypergolic propulsion systems. NASA-Marshall Space Flight Center (MSFC) in concert with industry partner Pratt & Whitney Rocketdyne (PWR) utilized a Space Act Agreement to test an oxygen/methane engine system in the Summer of 2010. PWR provided a 5,500 lbf (24,465 N) LOX/LCH4 regenerative cycle engine to demonstrate advanced thrust chamber assembly hardware and to evaluate the performance characteristics of the system. The chamber designs offered alternatives to traditional regenerative engine designs with improvements in cost and/or performance. MSFC provided the test stand, consumables and test personnel. The hot fire testing explored the effective cooling of one of the thrust chamber designs along with determining the combustion efficiency with variations of pressure and mixture ratio. The paper will summarize the status of these efforts.

Transpiration cooled throat for hydrocarbon rocket engines

NASA Technical Reports Server (NTRS)

May, Lee R.; Burkhardt, Wendel M.

1991-01-01

The objective for the Transpiration Cooled Throat for Hydrocarbon Rocket Engines Program was to characterize the use of hydrocarbon fuels as transpiration coolants for rocket nozzle throats. The hydrocarbon fuels investigated in this program were RP-1 and methane. To adequately characterize the above transpiration coolants, a program was planned which would (1) predict engine system performance and life enhancements due to transpiration cooling of the throat region using analytical models, anchored with available data; (2) a versatile transpiration cooled subscale rocket thrust chamber was designed and fabricated; (3) the subscale thrust chamber was tested over a limited range of conditions, e.g., coolant type, chamber pressure, transpiration cooled length, and coolant flow rate; and (4) detailed data analyses were conducted to determine the relationship between the key performance and life enhancement variables.

Advanced Small Rocket Chambers. Basic Program and Option 2: Fundamental Processes and Material Evaluation

NASA Technical Reports Server (NTRS)

Jassowski, Donald M.

1993-01-01

Propellants, chamber materials, and processes for fabrication of small high performance radiation cooled liquid rocket engines were evaluated to determine candidates for eventual demonstration in flight-type thrusters. Both storable and cryogenic propellant systems were considered. The storable propellant systems chosen for further study were nitrogen tetroxide oxidizer with either hydrazine or monomethylhydrazine as fuel. The cryogenic propellants chosen were oxygen with either hydrogen or methane as fuel. Chamber material candidates were chemical vapor deposition (CVD) rhenium protected from oxidation by CVD iridium for the chamber hot section, and film cooled wrought platinum-rhodium or regeneratively cooled stainless steel for the front end section exposed to partially reacted propellants. Laser diagnostics of the combustion products near the hot chamber surface and measurements at the surface layer were performed in a collaborative program at Sandia National Laboratories, Livermore, CA. The Material Sample Test Apparatus, a laboratory system to simulate the combustion environment in terms of gas and material temperature, composition, and pressure up to 6 Atm, was developed for these studies. Rocket engine simulator studies were conducted to evaluate the materials under simulated combustor flow conditions, in the diagnostic test chamber. These tests used the exhaust species measurement system, a device developed to monitor optically species composition and concentration in the chamber and exhaust by emission and absorption measurements.

A Continuous Adiabatic Demagnetization Refrigerator for Use with Mechanical Coolers

NASA Technical Reports Server (NTRS)

Shirron, P.; Abbondante, N.; Canavan, E.; DiPirro, M.; Grabowski, M.; Hirsch, M.; Jackson, M.; Tuttle, J.

2000-01-01

We have begun developing an adiabatic demagnetization refrigerator (ADR) which can produce continuous cooling at temperatures of 50 mK or lower, with high cooling power (goal of 10 PW). The design uses multiple stages to cascade heat from a continuously-cooled stage up to a heat sink. The serial arrangement makes it possible to add stages to extend the operating range to lower temperature, or to raise the heat rejection temperature. Compared to conventional single-shot ADRS, this system achieves higher cooling power per unit mass and is able to reject its heat at a more uniform rate. For operation with a mechanical cryocooler, this latter feature stabilizes the heat sink temperature and allows both the ADR and cryocooler to operate more efficiently. The ADR is being designed to operate with a heat sink as warm as 10-12 K to make it compatible with a wide variety of mechanical coolers as part of a versatile, cryogen-free low temperature cooling system. A two-stage system has been constructed and a proof-of-principle demonstration was conducted at 100 mK. Details of the design and test results, as well as the direction of future work, are discussed.

Light Optics for Optical Stochastic Cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andorf, Matthew; Lebedev, Valeri; Piot, Philippe

2016-06-01

In Optical Stochastic Cooling (OSC) radiation generated by a particle in a "pickup" undulator is amplified and transported to a downstream "kicker" undulator where it interacts with the same particle which radiated it. Fermilab plans to carry out both passive (no optical amplifier) and active (optical amplifier) tests of OSC at the Integrable Optics Test Accelerator (IOTA) currently in construction*. The performace of the optical system is analyzed with simulations in Synchrotron Radiation Workshop (SRW) accounting for the specific temporal and spectral properties of undulator radiation and being augmented to include dispersion of lens material.

Demonstration of Advanced C/SiC Cooled Ramp

NASA Technical Reports Server (NTRS)

Bouquet, Clement; Laithier, Frederic; Lawrence, Timothy; Eckel, Andrew; Munafo, Paul M. (Technical Monitor)

2002-01-01

Under a NASA contract, SPS is evaluating its C/SiC to metal brazing technique for the development of light, composite, actively cooled panels. The program first consisted of defining a system applicable to the X-33 nozzle ramp. SPS then performed evaluation tests for tube, composite, and braze material selection, and for the adaptation of braze process parameters to the parts geometry. SPS is presently manufacturing a 250x60 millimeter squared specimen, including 10 metallic tubes, which will be cycled in the NASA/GRC-CELL-22 test bed under engine representative conditions.

New PANDA Tests to Investigate Effects of Light Gases on Passive Safety Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paladino, D.; Auban, O.; Candreia, P.

The large- scale thermal-hydraulic PANDA facility (located at PSI in Switzerland), has been used over the last few years for investigating different passive decay- heat removal systems and containment phenomena for the next generation of light water reactors (Simplified Boiling Water Reactor: SBWR; European Simplified Boiling Water Reactor: ESBWR; Siedewasserreaktor: SWR-1000). Currently, as part of the European Commission 5. EURATOM Framework Programme project 'Testing and Enhanced Modelling of Passive Evolutionary Systems Technology for Containment Cooling' (TEMPEST), a new series of tests is being planned in the PANDA facility to experimentally investigate the distribution of non-condensable gases inside the containment andmore » their effect on the performance of the 'Passive Containment Cooling System' (PCCS). Hydrogen release caused by the metal-water reaction in the case of a postulated severe accident will be simulated in PANDA by injecting helium into the reactor pressure vessel. In order to provide suitable data for Computational Fluid Dynamic (CFD) code assessment and improvement, the instrumentation in PANDA has been upgraded for the new tests. In the present paper, a detailed discussion is given of the new PANDA tests to be performed to investigate the effects of light gas on passive safety systems. The tests are scheduled for the first half of the year 2002. (authors)« less

Combustion performance and heat transfer characterization of LOX/hydrocarbon type propellants

NASA Technical Reports Server (NTRS)

Michel, R. W.

1983-01-01

An evaluation liquid oxygen (LOX) and various hydrocarbon fuels as low cost alternative propellants suitable for future space transportation system applications was done. The emphasis was directed toward low earth orbit maneuvering engine and reaction control engine systems. The feasibility of regeneratively cooling an orbit maneuvering thruster was analytically determined over a range of operating conditions from 100 to 1000 psia chamber pressure and 1000 to 10,000-1bF thrust, and specific design points were analyzed in detail for propane, methane, RP-1, ammonia, and ethanol; similar design point studies were performed for a film-cooled reaction control thruster. Heat transfer characteristics of propane were experimentally evaluated in heated tube tests. Forced convection heat transfer coefficients were determined. Seventy-seven hot firing tests were conducted with LOX/propane and LOX/ethanol, for a total duration of nearly 1400 seconds, using both heat sink and water-cooled calorimetric chambers. Combustion performance and stability and gas-side heat transfer characteristics were evaluated.

Field test and simulation evaluation of variable refrigerant flow systems performance

DOE PAGES

Lee, Je Hyeon; Im, Piljae; Song, Young-hak

2017-10-24

Our study aims to compare the performance of a Variable Refrigerant Flow (VRF) system with a Roof Top Unit, (RTU) and a variable-air-volume (VAV) system through field tests and energy simulations. The field test was conducted in as similar conditions as possible between the two systems, such as the installation and operating environments of heating, the ventilation and air conditioning (HVAC) system, including internal heat gain and outdoor conditions, including buildings to compare the performance of the two systems accurately. A VRF system and RTU were installed at the test building located in Oak Ridge, Tennessee, in the USA. Themore » same internal heat gain was generated at the same operating time of the two systems using lighting, electric heaters, and humidifiers inside the building. The HVAC system was alternately operated between cooling and heating operations to acquire energy performance data and to compare energy usage. Furthermore, an hourly building energy simulation model was developed with regard to the VRF system and RTU, and then the model was calibrated using actual measured data. Then, annual energy consumption of the two systems were compared and analyzed using the calibrated model. Moreover, additional analysis was conducted when the controlled discharge air temperature in the RTU was changed. The field test result showed that when energy consumptions of two systems were compared at the same outdoor conditions, using the weather-normalized model, the VRF system exhibited an energy reduction of approximately 17% during cooling operation and of approximately 74% during heating operations. A comparison on the annual energy consumption using simulations showed that the VRF system reduced energy consumption more than that of the RTU by 60%. Furthermore, when the discharge air temperature in the RTU was controlled according to the outdoor air temperature, energy consumption of the RTU was reduced by 6% in cooling operations and by 18% in heating operation. As a result, energy consumption of the VRF system was reduced by more than that of the RTU by 55% approximately.« less

Field test and simulation evaluation of variable refrigerant flow systems performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Je Hyeon; Im, Piljae; Song, Young-hak

Our study aims to compare the performance of a Variable Refrigerant Flow (VRF) system with a Roof Top Unit, (RTU) and a variable-air-volume (VAV) system through field tests and energy simulations. The field test was conducted in as similar conditions as possible between the two systems, such as the installation and operating environments of heating, the ventilation and air conditioning (HVAC) system, including internal heat gain and outdoor conditions, including buildings to compare the performance of the two systems accurately. A VRF system and RTU were installed at the test building located in Oak Ridge, Tennessee, in the USA. Themore » same internal heat gain was generated at the same operating time of the two systems using lighting, electric heaters, and humidifiers inside the building. The HVAC system was alternately operated between cooling and heating operations to acquire energy performance data and to compare energy usage. Furthermore, an hourly building energy simulation model was developed with regard to the VRF system and RTU, and then the model was calibrated using actual measured data. Then, annual energy consumption of the two systems were compared and analyzed using the calibrated model. Moreover, additional analysis was conducted when the controlled discharge air temperature in the RTU was changed. The field test result showed that when energy consumptions of two systems were compared at the same outdoor conditions, using the weather-normalized model, the VRF system exhibited an energy reduction of approximately 17% during cooling operation and of approximately 74% during heating operations. A comparison on the annual energy consumption using simulations showed that the VRF system reduced energy consumption more than that of the RTU by 60%. Furthermore, when the discharge air temperature in the RTU was controlled according to the outdoor air temperature, energy consumption of the RTU was reduced by 6% in cooling operations and by 18% in heating operation. As a result, energy consumption of the VRF system was reduced by more than that of the RTU by 55% approximately.« less

Hanford spent nuclear fuel hot conditioning system test procedure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cleveland, K.J.

1997-09-16

This document provides the test procedures for cold testing of the prototype Hot Conditioning System (HCS) at the 306E Facility. The primary objective of this testing is to confirm design choices and provide data for the detailed design package prior to procurement of the process equipment. The current scope of testing in this document includes a fabricability study of the HCS, equipment performance testing of the HCS components, heat-up and cool-down cycle simulation, and robotic arm testing.

An Improved X-Band Maser System for Deep Space Network Applications

NASA Astrophysics Data System (ADS)

Britcliffe, M.; Hanson, T.; Fernandez, J.

2000-01-01

An 8450-MHz (X-band) maser system utilizing a commercial Gifford--McMahon (GM) closed-cycle cryocooler (CCR) was designed, fabricated, and demonstrated. The CCR system was used to cool a maser operating at 8450 MHz. The prototype GM CCR system meets or exceeds all Deep Space Network requirements for maser performance. The two-stage GM CCR operates at 4.2 K; for comparison, the DSN's current three-stage cryocooler, which uses a Joule--Thompson cooling stage in addition to GM cooling, operates at 4.5 K. The new CCR withstands heat loads of 1.5 W at 4.2 K as compared to 1 W at 4.5 K for the existing DSN cryocooler used for cooling masers. The measured noise temperature, T_e, of the maser used for these tests is defined at the ambient connection to the antenna feed system. The T_e measured 5.0 K at a CCR temperature of 4.5 K, about 1.5 K higher than the noise temperature of a typical DSN Block II-A X-band traveling-wave maser (TWM). Reducing the temperature of the CCR significantly lowers the maser noise temperature and increases maser gain and bandwidth. The new GM CCR gives future maser systems significant operational advantages, including reduced maintenance time and logistics requirements. The results of a demonstration of this new system are presented. Advantages of using a GM-cooled maser and the effects of the reduced CCR temperature on maser performance are discussed.

Cavity Control and Cooling of Nanoparticles in High Vacuum

NASA Astrophysics Data System (ADS)

Millen, James

2016-05-01

Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres, and control the rotation of nanorods, with the potential to produce cold, aligned nanostructures. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

Cavity Cooling of Nanoparticles: Towards Matter-Wave experiments

NASA Astrophysics Data System (ADS)

Millen, James; Kuhn, Stefan; Arndt, Markus

2016-05-01

Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres a few hundred nanometers in size. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

Effect of consecutive cooling and immobilization on catecholamine metabolism in rat tissues

NASA Technical Reports Server (NTRS)

Matlina, E. S.; Waysman, S. M.; Zaydner, I. G.; Kogan, B. M.; Nozdracheva, L. V.

1979-01-01

The combined effect of two stressor stimuli--cooling and immobilization--acting successively on the sympathetic-adrenaline system was studied experimentally in rats that were cooled for 8 hours at 7 C on the first day and immobilized for 6 hours on the next day. The biochemical and histochemical methods used and the experimental technique involved are described in detail. The following conclusions were formulated: (1) the successive action of cooling and immobilization results in a stronger decrease in the adrenaline and noradrenaline content in the adrenal gland than that which could be due to a simple summation of the cooling and immobilization effects; (2) successive cooling and immobilization are followed by activation of catecholamine synthesis in the adrenal gland; and (3) 1-DOPA administration (45 mg/kg 3 times in 2 days) intraabdominally activated catecholamine synthesis in the adrenal glands in both the control and test animals.

Thermodynamic transport properties of nitrogen tetroxide in hypercritical conditions for regenerative cooling of a rocket engine. Volume 1: Tests

NASA Astrophysics Data System (ADS)

Saccoccia, Giorgio

The thermodynamical and transport properties are studied for nitrogen tetroxide (N2O4), which is utilized in hypercritical conditions as oxidants and cooling fluids in rocket propulsion with regenerative cooling systems. An equation of state was performed in the varied zone of the state diagram, taking into account the phase change and two dissociation reactions. The study of the transport properties and state effects is based on the results of the fluid molecular theory. In addition to the state effects, the simple application results obtained for a case of thermal exchange in a cooling channel was studied through the behavior of the substance.

Heat rejection efficiency research of new energy automobile radiators

NASA Astrophysics Data System (ADS)

Ma, W. S.; Shen, W. X.; Zhang, L. W.

2018-03-01

The driving system of new energy vehicle has larger heat load than conventional engine. How to ensure the heat dissipation performance of the cooling system is the focus of the design of new energy vehicle thermal management system. In this paper, the heat dissipation efficiency of the radiator of the hybrid electric vehicle is taken as the research object, the heat dissipation efficiency of the radiator of the new energy vehicle is studied through the multi-working-condition enthalpy difference test. In this paper, the test method in the current standard QC/T 468-2010 “automobile radiator” is taken, but not limited to the test conditions specified in the standard, 5 types of automobile radiator are chosen, each of them is tested 20 times in simulated condition of different wind speed and engine inlet temperature. Finally, regression analysis is carried out for the test results, and regression equation describing the relationship of radiator heat dissipation heat dissipation efficiency air side flow rate cooling medium velocity and inlet air temperature is obtained, and the influence rule is systematically discussed.

Precooling of a dilution refrigerator

NASA Astrophysics Data System (ADS)

Pavlov, Valentin N.

A non-trivial system for Precooling of the dilution refrigerator for low-temperatureexperiments on an ISOL-facility is described in detail. Neither exchange gas in the vacuum jacket of the cryostat nor a demantable window in the 4K shield are used in this system. Instead of that the dilution refrigerator is supplemented with two capillaries and a heater in order to cool all low-temperature parts of the refrigerator down to start conditions. The, time of cooling depends on the total impedance of the first heat exchanger. Such system has been developed and tested in Dubna, and it is in operation.

JWST Observatory Integration and Test Status

NASA Astrophysics Data System (ADS)

McElwain, Michael; Bowers, Charles; Kimble, Randy; Niedner, Malcolm; Smith, Erin; JWST Project Team

2018-01-01

The James Webb Space Telescope (JWST) is a large (6.5 m) segmented aperture telescope equipped with near- and mid-infrared instruments (0.6-28 microns), all of which are passively cooled to ~40 K by a 5-layer sunshield while the mid-infrared instrument is actively cooled to 7 K. There are currently two major paths of development: the telescope and science instruments, called OTIS, and the sunshield and spacecraft, called the spacecraft element. Over the past year, there has been tremendous progress on the integration and testing of these two systems. We will present the current status of the JWST hardware and estimated performance metrics based upon the test activities.

Results from a scaled reactor cavity cooling system with water at steady state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lisowski, D. D.; Albiston, S. M.; Tokuhiro, A.

We present a summary of steady-state experiments performed with a scaled, water-cooled Reactor Cavity Cooling System (RCCS) at the Univ. of Wisconsin - Madison. The RCCS concept is used for passive decay heat removal in the Next Generation Nuclear Plant (NGNP) design and was based on open literature of the GA-MHTGR, HTR-10 and AVR reactor. The RCCS is a 1/4 scale model of the full scale prototype system, with a 7.6 m structure housing, a 5 m tall test section, and 1,200 liter water storage tank. Radiant heaters impose a heat flux onto a three riser tube test section, representingmore » a 5 deg. radial sector of the actual 360 deg. RCCS design. The maximum heat flux and power levels are 25 kW/m{sup 2} and 42.5 kW, and can be configured for variable, axial, or radial power profiles to simulate prototypic conditions. Experimental results yielded measurements of local surface temperatures, internal water temperatures, volumetric flow rates, and pressure drop along the test section and into the water storage tank. The majority of the tests achieved a steady state condition while remaining single-phase. A selected number of experiments were allowed to reach saturation and subsequently two-phase flow. RELAP5 simulations with the experimental data have been refined during test facility development and separate effects validation of the experimental facility. This test series represents the completion of our steady-state testing, with future experiments investigating normal and off-normal accident scenarios with two-phase flow effects. The ultimate goal of the project is to combine experimental data from UW - Madison, UI, ANL, and Texas A and M, with system model simulations to ascertain the feasibility of the RCCS as a successful long-term heat removal system during accident scenarios for the NGNP. (authors)« less

A nonventing cooling system for space environment extravehicular activity, using radiation and regenerable thermal storage

NASA Technical Reports Server (NTRS)

Bayes, Stephen A.; Trevino, Luis A.; Dinsmore, Craig E.

1988-01-01

This paper outlines the selection, design, and testing of a prototype nonventing regenerable astronaut cooling system for extravehicular activity space suit applications, for mission durations of four hours or greater. The selected system consists of the following key elements: a radiator assembly which serves as the exterior shell of the portable life support subsystem backpack; a layer of phase change thermal storage material, n-hexadecane paraffin, which acts as a regenerable thermal capacitor; a thermoelectric heat pump; and an automatic temperature control system. The capability for regeneration of thermal storage capacity with and without the aid of electric power is provided.

Crawl space assisted heat pump. [using stored ground heat

NASA Technical Reports Server (NTRS)

Ternes, M. P.

1980-01-01

A variety of experiments and simulations, currently being designed or underway, to determine the feasibility of conditioning the source air of an air to air heat pump using stored ground heat or cool to produce higher seasonal COP's and net energy savings are discussed. The ground would condition ambient air as it is drawn through the crawl space of a house. Tests designed to evaluate the feasibility of the concept, to determine the amount of heat or cool available from the ground, to study the effect of the system on the heating and cooling loads of the house, to study possible mechanisms which could enhance heat flow through the ground, and to determine if diurnal temperature swings are necessary to achieve successful system performance are described.

The design of a solar energy collection system to augment heating and cooling for a commercial office building

NASA Technical Reports Server (NTRS)

Basford, R. C.

1977-01-01

Analytical studies supported by experimental testing indicate that solar energy can be utilized to heat and cool commercial buildings. In a 50,000 square foot one-story office building at the Langley Research Center, 15,000 square feet of solar collectors are designed to provide the energy required to supply 79 percent of the building heating needs and 52 percent of its cooling needs. The experience gained from the space program is providing the technology base for this project. Included are some of the analytical studies made to make the building design changes necessary to utilize solar energy, the basic solar collector design, collector efficiencies, and the integrated system design.

Control of biological growth in recirculating cooling systems using treated secondary effluent as makeup water with monochloramine.

PubMed

Chien, Shih-Hsiang; Chowdhury, Indranil; Hsieh, Ming-Kai; Li, Heng; Dzombak, David A; Vidic, Radisav D

2012-12-01

Secondary-treated municipal wastewater, an abundant and widely distributed impaired water source, is a promising alternative water source for thermoelectric power plant cooling. However, excessive biological growth is a major challenge associated with wastewater reuse in cooling systems as it can interfere with normal system operation as well as enhance corrosion and scaling problems. Furthermore, possible emission of biological aerosols (e.g., Legionella pneumophila) with the cooling tower drift can lead to public health concerns within the zone of aerosol deposition. In this study, the effectiveness of pre-formed and in-situ-formed monochloramine was evaluated for its ability to control biological growth in recirculating cooling systems using secondary-treated municipal wastewater as the only makeup water source. Bench-scale studies were compared with pilot-scale studies for their ability to predict system behavior under realistic process conditions. Effectiveness of the continuous addition of pre-formed monochloramine and monochloramine formed in-situ through the reaction of free chlorine with ammonia in the incoming water was evaluated in terms of biocide residual and its ability to control both planktonic and sessile microbial populations. Results revealed that monochloramine can effectively control biofouling in cooling systems employing secondary-treated municipal wastewater and has advantages relative to use of free chlorine, but that bench-scale studies seriously underestimate biocide dose and residual requirements for proper control of biological growth in full-scale systems. Pre-formed monochloramine offered longer residence time and more reliable performance than in-situ-formed monochloramine due to highly variable ammonia concentration in the recirculating water caused by ammonia stripping in the cooling tower. Pilot-scale tests revealed that much lower dosing rate was required to maintain similar total chlorine residual when pre-formed monochloramine was used as compared to in-situ-formed monochloramine. Adjustment of biocide dose to maintain monochloramine residual above 3mg/L is needed to achieve successful biological growth control in recirculating cooling systems using secondary-treated municipal effluent as the only source of makeup water. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison of central axis and jet ring coolant supply for turbine disk cooling on a SSME-HPOTP model

NASA Technical Reports Server (NTRS)

Kim, Y. W.; Metzger, D. E.

1992-01-01

The test facility, test methods and results are presented for an experimental study modeling the cooling of turbine disks in the blade attachment regions with multiple impinging jets, in a configuration simulating the disk cooling method employed on the Space Shuttle Main Engine oxygen turbopump. The study's objective was to provide a comparison of detailed local convection heat transfer rates obtained for a single center-supply of disk coolant with those obtained with the present flight configuration where disk coolant is supplied through an array of 19 jets located near the disk outer radius. Specially constructed disk models were used in a program designed to evaluate possible benefits and identify any possible detrimental effects involved in employing an alternate disk cooling scheme. The study involved the design, construction and testing of two full scale rotating model disks, one plane and smooth for baseline testing and the second contoured to the present flight configuration, together with the corresponding plane and contoured stator disks. Local heat transfer rates are determined from the color display of encapsulated liquid crystals coated on the disk in conjunction with use of a computer vision system. The test program was composed of a wide variety of disk speeds, flowrates, and geometrical configurations, including testing for the effects of disk boltheads and gas ingestion from the gas path region radially outboard of the disk-cavity.

Controlled cooling of an electronic system for reduced energy consumption

DOE Office of Scientific and Technical Information (OSTI.GOV)

David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

Energy efficient control of a cooling system cooling an electronic system is provided. The control includes automatically determining at least one adjusted control setting for at least one adjustable cooling component of a cooling system cooling the electronic system. The automatically determining is based, at least in part, on power being consumed by the cooling system and temperature of a heat sink to which heat extracted by the cooling system is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the coolingmore » system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on one or more experimentally obtained models relating the targeted temperature and power consumption of the one or more adjustable cooling components of the cooling system.« less

Performance data for a desuperheater integrated to a thermal energy storage system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, A.H.W.; Jones, J.W.

1995-11-01

Desuperheaters are heat exchangers that recover heat from the compressor discharge gas to heat domestic hot water. The objective of this project was to conduct performance tests for a desuperheater in the cooling and heating modes of a thermal energy storage system so as to form a data base on the steady state performance of a residential desuperheater unit. The desuperheater integrated to a thermal energy storage system was installed in the Dual-Air Loop Test Facility at The Center for Energy Studies, the University of Texas at Austin. The major components of the system consist of the refrigerant compressor, domesticmore » hot water (DHW) desuperheater, thermal storage tank with evaporator/condenser coil, outdoor air coil, DHW storage tank, DHW circulating pump, space conditioning water circulation pump, and indoor heat exchanger. Although measurements were made to quantity space heating, space cooling, and domestic water heating, this paper only emphasizes the desuperheater performance of the unit. Experiments were conducted to study the effects of various outdoor temperature and entering water temperature on the performance of the desuperheater/TES system. In the cooling and heating modes, the desuperheater captured 5 to 18 percent and 8 to 17 percent, respectively, of the heat that would be normally rejected through the air coil condenser. At higher outdoor temperature, the desuperheater captured more heat. it was also noted that the heating and cooling COPs decreased with entering water temperature. The information generated in the experimental efforts could be used to form a data base on the steady state performance of a residential desuperheater unit.« less

Infrared detectors and test technology of cryogenic camera

NASA Astrophysics Data System (ADS)

Yang, Xiaole; Liu, Xingxin; Xing, Mailing; Ling, Long

2016-10-01

Cryogenic camera which is widely used in deep space detection cools down optical system and support structure by cryogenic refrigeration technology, thereby improving the sensitivity. Discussing the characteristics and design points of infrared detector combined with camera's characteristics. At the same time, cryogenic background test systems of chip and detector assembly are established. Chip test system is based on variable cryogenic and multilayer Dewar, and assembly test system is based on target and background simulator in the thermal vacuum environment. The core of test is to establish cryogenic background. Non-uniformity, ratio of dead pixels and noise of test result are given finally. The establishment of test system supports for the design and calculation of infrared systems.

Rapid Identification of a Cooling Tower-Associated Legionnaires’ Disease Outbreak Supported by Polymerase Chain Reaction Testing of Environmental Samples, New York City, 2014–2015

PubMed Central

Benowitz, Isaac; Fitzhenry, Robert; Boyd, Christopher; Dickinson, Michelle; Levy, Michael; Lin, Ying; Nazarian, Elizabeth; Ostrowsky, Belinda; Passaretti, Teresa; Rakeman, Jennifer; Saylors, Amy; Shamoonian, Elena; Smith, Terry-Ann; Balter, Sharon

2018-01-01

We investigated an outbreak of eight Legionnaires’ disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings. PMID:29780175

Experimental investigations of thermophysical properties of some paraffin waxes industrially manufactured in Poland

NASA Astrophysics Data System (ADS)

Zbińkowski, Piotr; Zmywaczyk, Janusz; Koniorczyk, Piotr

2017-07-01

Phase-change materials (PCM) can be applied as a heat absorbing/releasing medium in passive cooling systems. Such systems can be used in cooling and temperature stabilization of electronic components, i.e., Li-ion batteries, photovoltaic modules or light emitting diodes (LED). In order to optimize heat transfer in passive cooling systems experimental studies of PCM thermophysical properties are necessary. A good PCM candidate for passive cooling systems may be paraffin waxes due to their relatively high latent heat of fusion (L 200 J.g-1), suitable for working of electronic devices range of melting temperatures (22 °C - 68 °C) and a reasonable price. However, their main drawback is a relatively low thermal conductivity k ranging from 0.148 W.m-1.K-1 to 0.358 W.m-1.K-1. In this paper were presented results of experimentally determined temperature characteristics of thermophysical parameters of four paraffin waxes industrially manufactured in Jasło/Poland by POLWAX. The density ρ of the test paraffin waxes determined at room temperature (20 °C) using a laboratory balance RADWAG X/60/220 comprised from 0.82 g.cm-3 to 0.94 g.cm-3. The thermal diffusivity κ of paraffin waxes was tested within temperature range from -50 °C to 30 °C every 20 °C interval using the NETZSCH LFA 467 HyperFlash. The test specimens having form of cylinder were 12.7 mm in diameter and 2.15 - 2.20 mm in height. Prior to the experiment the face and the back surface of each specimen were coated with a thin layer of graphite 33 having a thickness of several micrometers in accordance with the recommendation given by NETZSCH. The thermal diffusivity of the test paraffin waxes within temperature interval -40 °C - 20 °C was determined to be 0.083 mm2.s-1 to 0.216 mm2.s-1. Thermal effects and the apparent heat capacity cp of the tested materials were measured in the temperature range from -10 °C to 100 °C using the NETZSCH DSC 404 F1 Pegasus at 10 K.min-1 heating/cooling rates in an atmosphere of helium as an inert gas. Thermal degradation studies of the test specimens were carried out in TG/DTG analysis, using NETZSCH STA 2500 Regulus within temperature range from 30 °C - 800 °C. The results of the heat capacity obtained by using DSC method and determined from the LFA 467 thermal diffusivity measurements due to applying Pyroceram 9606 as a reference material of known thermophysical properties were compared with each other. The thermal conductivity k of the tested paraffin waxes was evaluated using a well-known relationship k = κ . ρ . cp. In the investigated temperature range from -40 °C to 20 °C the thermal conductivity of the test paraffin waxes was changing from 0.157 W.m-1.K-1 to 0.282 W.m-1.K-1. DSC investigations revealed that the phase-change transition connected with the melting of the test paraffin waxes was a two-step, and in case of LUXOLINA ST, it was a three-step process (solid-solid and then solid-liquid) within temperature range from 30 °C to 65 °C as determined from the onset. The current studies of determining thermophysical properties of some paraffin waxes are treated as a starting point for selecting the most adequate PCM candidate for passive cooling systems of high-power LED street lamp.

Testing Numerical Models of Cool Core Galaxy Cluster Formation with X-Ray Observations

NASA Astrophysics Data System (ADS)

Henning, Jason W.; Gantner, Brennan; Burns, Jack O.; Hallman, Eric J.

2009-12-01

Using archival Chandra and ROSAT data along with numerical simulations, we compare the properties of cool core and non-cool core galaxy clusters, paying particular attention to the region beyond the cluster cores. With the use of single and double β-models, we demonstrate a statistically significant difference in the slopes of observed cluster surface brightness profiles while the cluster cores remain indistinguishable between the two cluster types. Additionally, through the use of hardness ratio profiles, we find evidence suggesting cool core clusters are cooler beyond their cores than non-cool core clusters of comparable mass and temperature, both in observed and simulated clusters. The similarities between real and simulated clusters supports a model presented in earlier work by the authors describing differing merger histories between cool core and non-cool core clusters. Discrepancies between real and simulated clusters will inform upcoming numerical models and simulations as to new ways to incorporate feedback in these systems.

Greenbuilt Retrofit Test House Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sparn, B.; Hudon, K.; Earle, L.

2014-06-01

The Greenbuilt house is a 1980's era house in the Sacramento area that was a prominent part of Sacramento Municipal Utility District's (SMUD) Energy Efficient Remodel Demonstration Program. The house underwent an extensive remodel, aimed at improving overall energy efficiency with a goal of reducing the home's energy use by 50%. NREL researchers performed a number of tests on the major systems touched by the retrofit to ensure they were working as planned. Additionally, SMUD rented the house from Greenbuilt Construction for a year to allow NREL to perform a number of tests on the cooling system and the watermore » heating system. The goal of the space conditioning tests was to find the best ways to cut cooling loads and shift the summer peak. The water heating system, comprised of an add-on heat pump water heater and an integrated collector-storage solar water heater, was operated with a number of different draw profiles to see how varying hot water draw volume and schedule affected the performance of the system as a whole. All the experiments were performed with the house empty, with a simulated occupancy schedule running in the house to mimic the load imposed by real occupants.« less

46 CFR 153.432 - Cooling systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a manual...

46 CFR 153.432 - Cooling systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a manual...

46 CFR 153.432 - Cooling systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a manual...

46 CFR 153.432 - Cooling systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a manual...

40 CFR 86.884-12 - Test run.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Test run. 86.884-12 Section 86.884-12... Engines; Smoke Exhaust Test Procedure § 86.884-12 Test run. (a) The temperature of the air supplied to the... taken for each test: (1) Start cooling system; (2) Warm up the engine by the procedure described in 40...

40 CFR 86.884-12 - Test run.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Test run. 86.884-12 Section 86.884-12... Heavy-Duty Engines; Smoke Exhaust Test Procedure § 86.884-12 Test run. (a) The temperature of the air... steps shall be taken for each test: (1) Start cooling system; (2) Warm up the engine by the procedure...

Study of Fluid Cooling Loop System in Chinese Manned Spacecraft

NASA Astrophysics Data System (ADS)

Jiang, Jun; Xu, Jiwan; Fan, Hanlin; Huang, Jiarong

2002-01-01

change. To solve the questions, a fluid cooling loop system must be applied to Chinese manned spacecraft besides other conventional thermal control methods, such as thermal control coatings, multiplayer insulation blankets, heat pipes, electro-heating adjustment temperature devices, and so on. The paper will introduce the thermal design of inner and outer fluid loop including their constitution and fundamental, etc. The capability of heat transportation and the accuracy of control temperature for the fluid loop will be evaluated and analyzed. To insure the air temperature of sealed cabins within 21+/-4, the inlet liquid temperature of condensing heat exchanger needs to be controlled within 9+/-2. To insure this, the inlet liquid temperature of middle heat exchanger needs to be controlled within 8+/-1.8. The inlet temperature point is controlled by a subsidiary loop adjusting: when the computer receives feedbacks of the deviation and the variety rate of deviation from the controlled temperature point. It drives the temperature control valve to adjust the flow flux distribution between the main loop through radiator and the subsidiary loop which isn't through radiator to control the temperature of the mixed fluid within 8+/-1.8. The paper will also introduce thermal designs of key parts in the cooling loop, such as space radiators, heat exchangers and cooling plates. Thermal simulated tests on the ground and flight tests have been performed to verify correctness of thermal designs. rational and the loop system works order. It realizes the circulation of absorbing heat dissipation to the loop and transferring it to radiator then radiating it to space. (2) loop control system controls inlet temperature of middle heat exchanger within 8+/-1.8 under various thermal cases. Thermal design of the middle heat exchanger insures inlet temperature of condensing heat within 9+/-2. Thereby, the air temperature of sealed cabins is controlled within about 21+/-4 accurately. (3) The thermal designs of the key heat exchanging parts (such as radiator, heat exchangers and cooling plates) in the cooling loop are rational and effective, they meet the requirements of heat exchanging and assure the entire system work order.

Corrosion inhibitors for solar heating and cooling systems

NASA Technical Reports Server (NTRS)

Humphries, T. S.

1978-01-01

Inhibitors which appeared promising in previous tests and additional inhibitors including several proprietary products were evaluated. Evaluation of the inhibitors was based on corrosion protection afforded an aluminum-mild steel-copper-stainless steel assembly in a hot corrosive water. Of the inhibitors tested two were found to be effective and show promise for protecting multimetallic solar heating systems.

14 CFR Appendix C to Part 27 - Criteria for Category A

Code of Federal Regulations, 2013 CFR

2013-01-01

... unless it meets the design installation and performance requirements contained in this appendix in... drive system: Design. 29.927(c)(1)—Additional tests. 29.953(a)—Fuel system independence. 29.1027(a)—Transmission and gearboxes: General. 29.1045(a)(1), (b), (c), (d), and (f)—Climb cooling test procedures. 29...

Verification of passive cooling techniques in the Super-FRS beam collimators

NASA Astrophysics Data System (ADS)

Douma, C. A.; Gellanki, J.; Najafi, M. A.; Moeini, H.; Kalantar-Nayestanaki, N.; Rigollet, C.; Kuiken, O. J.; Lindemulder, M. F.; Smit, H. A. J.; Timersma, H. J.

2016-08-01

The Super FRagment Separator (Super-FRS) at the FAIR facility will be the largest in-flight separator of heavy ions in the world. One of the essential steps in the separation procedure is to stop the unwanted ions with beam collimators. In one of the most common situations, the heavy ions are produced by a fission reaction of a primary 238U-beam (1.5 GeV/u) hitting a 12C target (2.5 g/cm2). In this situation, some of the produced ions are highly charged states of 238U. These ions can reach the collimators with energies of up to 1.3 GeV/u and a power of up to 500 W. Under these conditions, a cooling system is required to prevent damage to the collimators and to the corresponding electronics. Due to the highly radioactive environment, both the collimators and the cooling system must be suitable for robot handling. Therefore, an active cooling system is undesirable because of the increased possibility of malfunctioning and other complications. By using thermal simulations (performed with NX9 of Siemens PLM), the possibility of passive cooling is explored. The validity of these simulations is tested by independent comparison with other simulation programs and by experimental verification. The experimental verification is still under analysis, but preliminary results indicate that the explored passive cooling option provides sufficient temperature reduction.

76 FR 82323 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-30

... NUCLEAR REGULATORY COMMISSION [NRC-2011-0296] Design, Inspection, and Testing Criteria for Air... for public comment draft regulatory guide (DG), DG-1274, ``Design, Inspection, and Testing Criteria... Systems in Light-Water-Cooled Nuclear Power Plants.'' This guide applies to the design, inspection, and...

Tests of the MICE Electron Muon Ranger frontend electronics with a small scale prototype

NASA Astrophysics Data System (ADS)

Bolognini, D.; Bene, P.; Blondel, A.; Cadoux, F.; Debieux, S.; Giannini, G.; Graulich, J. S.; Lietti, D.; Masciocchi, F.; Prest, M.; Rothenfusser, K.; Vallazza, E.; Wisting, H.

2011-08-01

The MICE experiment is being commissioned at RAL to demonstrate the feasibility of the muon ionization cooling technique for future applications such as the Neutrino Factory and the Muon Collider. The cooling will be evaluated by measuring the emittance before and after the cooling channel with two 4 T spectrometers; to distinguish muons from the background, a multi-detector particle identification system is foreseen: three Time of Flight stations, two Cherenkov counters and a calorimetric system consisting of a pre-shower layer and a fully active scintillator detector (EMR) are used to discriminate muons from pions and electrons. EMR consists of 48 planes of triangular scintillating bars coupled to WLS fibers readout by single PMTs on one side and MAPMTs on the other; each plane sensible area is 1 m 2. This article deals with a small scale prototype of the EMR detector which has been used to test the MAPMT frontend electronics based on the MAROC ASIC; the tests with cosmic rays using both an analog mode and a digital readout mode are presented. A very preliminary study on the cross talk problem is also shown.

Surface Power Radiative Cooling Tests

NASA Astrophysics Data System (ADS)

Vaughn, Jason; Schneider, Todd

2006-01-01

Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. ~5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Cooling test procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling test procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

Transpiration Cooling Experiment

NASA Technical Reports Server (NTRS)

Song, Kyo D.; Ries, Heidi R.; Scotti, Stephen J.; Choi, Sang H.

1997-01-01

The transpiration cooling method was considered for a scram-jet engine to accommodate thermally the situation where a very high heat flux (200 Btu/sq. ft sec) from hydrogen fuel combustion process is imposed to the engine walls. In a scram-jet engine, a small portion of hydrogen fuel passes through the porous walls of the engine combustor to cool the engine walls and at the same time the rest passes along combustion chamber walls and is preheated. Such a regenerative system promises simultaneously cooling of engine combustor and preheating the cryogenic fuel. In the experiment, an optical heating method was used to provide a heat flux of 200 Btu/sq. ft sec to the cylindrical surface of a porous stainless steel specimen which carried helium gas. The cooling efficiencies by transpiration were studied for specimens with various porosity. The experiments of various test specimens under high heat flux have revealed a phenomenon that chokes the medium flow when passing through a porous structure. This research includes the analysis of the system and a scaling conversion study that interprets the results from helium into the case when hydrogen medium is used.

Thermal Performance Testing of EMU and CSAFE Liquid Cooling Garments

NASA Technical Reports Server (NTRS)

Rhodes, Richard; Bue, Grant; Hakam, Mark; Radford, Tamara

2013-01-01

Future exploration missions require the development of a new liquid cooling garment (LCG) that offers greater system reliability, is more comfortable, and maximizes thermal performance. To inform the development of a future LCG a thermal performance test was conducted to evaluate three factors: (1) the effect of the thermal comfort undergarment (TCU) on tactile and thermal comfort, (2) the comparable thermal performance of an CSAFE developed engineering evaluation unit (EEU) LCG, which uses a commercial-off-the-shelf (COTS) wicking garment as the base, and (3) the performance of a torso or upper body only LCG configuration to evaluate a proposed auxiliary loop configuration. To evaluate the thermal performance of each configuration a metabolic suit test was conducted, utilizing suited subjects to generate metabolic heat by walking on a treadmill at various speeds. Three (3) test subjects of similar height and weight produced a metabolic load for five tests by either resting (300-600 BTU/hr), walking at a slow pace (1200 BTU/hr), and walking at a brisk pace (2200 BTU/hr). During the test, data was collected that would allow us to track the heat transfer to the LCG and ventilation system to determine the thermal performance of the LCG configurations. Four different test configurations were tested, with one configuration tested twice. The test results show that the CSAFE EEU LCG and EMU LCG had comparable performance. The testing also showed that an auxiliary loop LCG, sized similarly to the shirt-only configuration, should provide adequate cooling for contingency scenarios. Finally, the testing showed the previous analysis that assumed a UA deterioration from the TCU was too conservative and the TCU may prove to be acceptable for future development with additional analysis and testing.

Posttest analysis of MIST Test 330302 using TRAC-PF1/MOD1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boyack, B E

This report discusses a posttest analysis of Multi-Loop Integral System Test (MIST) 330302 which has been performed using TRAC-PF1/MOD1. This test was one of group performed in the MIST facility to investigate high-pressure injection (HPI)-power-operated relief valve (PORV) cooling, also known as feed-and-bleed cooling. In Test 330302, HPI cooling was delayed 20 min after opening and locking the PORV open to induce extensive system voiding. We have concluded that the TRAC-calculated results are in reasonable overall agreement with the data for Test 330302. All major trends and phenomena were correctly predicted. Differences observed between the measured and calculated results havemore » been traced and related, in part, to deficiencies in our knowledge of the facility configuration and operation. We have identified two models forwhich additional review is appropriate. However, in general, the TRAC closure models and correlations appear to be adequate for the prediction of the phenomena expected to occur during feed-and-bleed transientsin the MIST facility. We believe that the correct conclusions about trends and phenomena will be reached if the code is used in similar applications. Conclusions reached regarding use of the code to calculate similar phenomena in full-size plants (scaling implications) and regulatory implications of this work are also presented.« less

Experimental and Analytical Investigation of the Coolant Flow Characteristics in Cooled Turbine Airfoils

NASA Technical Reports Server (NTRS)

Damerow, W. P.; Murtaugh, J. P.; Burggraf, F.

1972-01-01

The flow characteristics of turbine airfoil cooling system components were experimentally investigated. Flow models representative of leading edge impingement, impingement with crossflow (midchord cooling), pin fins, feeder supply tube, and a composite model of a complete airfoil flow system were tested. Test conditions were set by varying pressure level to cover the Mach number and Reynolds number range of interest in advanced turbine applications. Selected geometrical variations were studied on each component model to determine these effects. Results of these tests were correlated and compared with data available in the literature. Orifice flow was correlated in terms of discharge coefficients. For the leading edge model this was found to be a weak function of hole Mach number and orifice-to-impinged wall spacing. In the impingement with crossflow tests, the discharge coefficient was found to be constant and thus independent of orifice Mach number, Reynolds number, crossflow rate, and impingement geometry. Crossflow channel pressure drop showed reasonable agreement with a simple one-dimensional momentum balance. Feeder tube orifice discharge coefficients correlated as a function of orifice Mach number and the ratio of the orifice-to-approach velocity heads. Pin fin data was correlated in terms of equivalent friction factor, which was found to be a function of Reynolds number and pin spacing but independent of pin height in the range tested.

Thermal System Verification and Model Validation for NASA's Cryogenic Passively Cooled James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Cleveland, Paul E.; Parrish, Keith A.

2005-01-01

A thorough and unique thermal verification and model validation plan has been developed for NASA s James Webb Space Telescope. The JWST observatory consists of a large deployed aperture optical telescope passively cooled to below 50 Kelvin along with a suite of several instruments passively and actively cooled to below 37 Kelvin and 7 Kelvin, respectively. Passive cooling to these extremely low temperatures is made feasible by the use of a large deployed high efficiency sunshield and an orbit location at the L2 Lagrange point. Another enabling feature is the scale or size of the observatory that allows for large radiator sizes that are compatible with the expected power dissipation of the instruments and large format Mercury Cadmium Telluride (HgCdTe) detector arrays. This passive cooling concept is simple, reliable, and mission enabling when compared to the alternatives of mechanical coolers and stored cryogens. However, these same large scale observatory features, which make passive cooling viable, also prevent the typical flight configuration fully-deployed thermal balance test that is the keystone to most space missions thermal verification plan. JWST is simply too large in its deployed configuration to be properly thermal balance tested in the facilities that currently exist. This reality, when combined with a mission thermal concept with little to no flight heritage, has necessitated the need for a unique and alternative approach to thermal system verification and model validation. This paper describes the thermal verification and model validation plan that has been developed for JWST. The plan relies on judicious use of cryogenic and thermal design margin, a completely independent thermal modeling cross check utilizing different analysis teams and software packages, and finally, a comprehensive set of thermal tests that occur at different levels of JWST assembly. After a brief description of the JWST mission and thermal architecture, a detailed description of the three aspects of the thermal verification and model validation plan is presented.

Design of High Voltage Electrical Breakdown Strength measuring system at 1.8K with a G-M cryocooler

NASA Astrophysics Data System (ADS)

Li, Jian; Huang, Rongjin; Li, Xu; Xu, Dong; Liu, Huiming; Li, Laifeng

2017-09-01

Impregnating resins as electrical insulation materials for use in ITER magnets and feeder system are required to be radiation stable, good mechanical performance and high voltage electrical breakdown strength. In present ITER project, the breakdown strength need over 30 kV/mm, for future DEMO reactor, it will be greater than this value. In order to develop good property insulation materials to satisfy the requirements of future fusion reactor, high voltage breakdown strength measurement system at low temperature is necessary. In this paper, we will introduce our work on the design of this system. This measuring system has two parts: one is an electrical supply system which provides the high voltage from a high voltage power between two electrodes; the other is a cooling system which consists of a G-M cryocooler, a superfluid chamber and a heat switch. The two stage G-M cryocooler pre-cool down the system to 4K, the superfluid helium pot is used for a container to depress the helium to superfluid helium which cool down the sample to 1.8K and a mechanical heat switch connect or disconnect the cryocooler and the pot. In order to provide the sufficient time for the test, the cooling system is designed to keep the sample at 1.8K for 300 seconds.

Lockheed Martin microcryocoolers

NASA Astrophysics Data System (ADS)

Olson, Jeffrey R.; Roth, Eric W.; Sanders, Lincoln-Shaun; Will, Eric; Frank, David J.

2017-05-01

Lockheed Martin's Advanced Technology Center, part of Lockheed Martin Space Systems Company, has developed a series of long life microcryocoolers for avionics and space sensor applications. We report the development and testing of three varieties of single-stage, compact, coaxial, pulse tube microcryocoolers. These coolers support emerging large, high operating temperature (100-150K) infrared focal plane array sensors with nominal cooling loads of 200-2000 mW, and all share long life technology attributes used in space cryocoolers, which typically provide 10 years of continuous operation on orbit without degradation. These three models of microcryocooler are the 345 gram Micro1-1, designed to provide 1 W cooling at 150 K, the 450 gram Micro1-2, designed to provide 2 W cooling at 105 K, and the 320 gram Micro1-3, designed to provide 300 mW cooling at 125 K while providing the capability to cool the IR focal plane to 125 K in less than 3 minutes. The Micro1-3 was also designed with a highly compact package that reduced the coldhead length to 55 mm, a length reduction of more than a factor of two compared with the other coldheads. This paper also describes recent design studies of 2-stage microcryocoolers capable of providing cooling at 25-100K. LMSSC is an industry leader in multiple-stage coolers, having successfully built and tested eight 2-stage coolers (typically cooling to 35-55K), and four coolers with 3 or 4 stages (for cooling to 4-10K). The 2-stage microcryocooler offers a very low mass and compact package capable of cooling HgCdTe focal planes, while providing simultaneous optics cooling at a higher temperature.

Prototype solar heating and cooling systems

NASA Technical Reports Server (NTRS)

1979-01-01

A combination of monthly progress reports are presented. It contains a summary of activities and progress made from November 1, 1978, to February 28, 1979. The effort calls for the development, manufacture, test, system installation, maintenance, problem resolution, and performance evaluation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

Energy efficient control of a cooling system cooling an electronic system is provided. The control includes automatically determining at least one adjusted control setting for at least one adjustable cooling component of a cooling system cooling the electronic system. The automatically determining is based, at least in part, on power being consumed by the cooling system and temperature of a heat sink to which heat extracted by the cooling system is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the coolingmore » system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on one or more experimentally obtained models relating the targeted temperature and power consumption of the one or more adjustable cooling components of the cooling system.« less

Develop and test fuel cell powered on-site integrated total energy systems. Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Feigenbaum, H.; Kaufman, A.; Wang, C. L.; Werth, J.; Whelan, J. A.

1983-01-01

Operating experience with a 5kW methanol-air integrated system is described. On-going test results for a 24-cell, two-sq ft (4kW) stack are reported. The main activity for this stack is currently the evaluation of developmental non-metalic cooling plates. Single-cell test results are presented for a promising developmental cathode catalyst.

Sideband cooling of micromechanical motion to the quantum ground state.

PubMed

Teufel, J D; Donner, T; Li, Dale; Harlow, J W; Allman, M S; Cicak, K; Sirois, A J; Whittaker, J D; Lehnert, K W; Simmonds, R W

2011-07-06

The advent of laser cooling techniques revolutionized the study of many atomic-scale systems, fuelling progress towards quantum computing with trapped ions and generating new states of matter with Bose-Einstein condensates. Analogous cooling techniques can provide a general and flexible method of preparing macroscopic objects in their motional ground state. Cavity optomechanical or electromechanical systems achieve sideband cooling through the strong interaction between light and motion. However, entering the quantum regime--in which a system has less than a single quantum of motion--has been difficult because sideband cooling has not sufficiently overwhelmed the coupling of low-frequency mechanical systems to their hot environments. Here we demonstrate sideband cooling of an approximately 10-MHz micromechanical oscillator to the quantum ground state. This achievement required a large electromechanical interaction, which was obtained by embedding a micromechanical membrane into a superconducting microwave resonant circuit. To verify the cooling of the membrane motion to a phonon occupation of 0.34 ± 0.05 phonons, we perform a near-Heisenberg-limited position measurement within (5.1 ± 0.4)h/2π, where h is Planck's constant. Furthermore, our device exhibits strong coupling, allowing coherent exchange of microwave photons and mechanical phonons. Simultaneously achieving strong coupling, ground state preparation and efficient measurement sets the stage for rapid advances in the control and detection of non-classical states of motion, possibly even testing quantum theory itself in the unexplored region of larger size and mass. Because mechanical oscillators can couple to light of any frequency, they could also serve as a unique intermediary for transferring quantum information between microwave and optical domains.

Summary of NASA-Lewis Research Center solar heating and cooling and wind energy programs

NASA Technical Reports Server (NTRS)

Vernon, R. W.

1975-01-01

NASA is planning to construct and operate a solar heating and cooling system in conjunction with a new office building being constructed at Langley Research Center. The technology support for this project will be provided by a solar energy program underway at NASA's Lewis Research Center. The solar program at Lewis includes: testing of solar collectors with a solar simulator, outdoor testing of collectors, property measurements of selective and nonselective coatings for solar collectors, and a solar model-systems test loop. NASA-Lewis has been assisting the National Science Foundation and now the Energy Research and Development Administration in planning and executing a national wind energy program. The areas of the wind energy program that are being conducted by Lewis include: design and operation of a 100 kW experimental wind generator, industry-designed and user-operated wind generators in the range of 50 to 3000 kW, and supporting research and technology for large wind energy systems. An overview of these activities is provided.

Development of a Prototype Water Pump for Future Space Suit Applications

NASA Technical Reports Server (NTRS)

Hartman, David; Hodgson, Edward; Dionne, Steven; Gervais, Edward, III; Trevino, Luis

2009-01-01

NASA's next generation of space suit systems will place new demands on the pump used to circulate cooling water through the life support system and the crew's liquid cooling garment. Long duration missions and frequent EVA require increased durability and reliability; limited resupply mass requirements demand compatibility with recycled water, and changing system design concepts demand increased tolerance for dissolved and free gas and the ability to operate over a broader range of flow rates and discharge pressure conditions. This paper describes the development of a positive displacement prototype pump to meet these needs. A gerotor based design has been adapted to meet pump performance, gas tolerance, and durability requirements while providing a small, lightweight pump assembly. This design has been detailed and implemented using materials selected to address anticipated water quality and mission needs as a prototype unit for testing in NASA laboratories. Design requirements, pump technology selection and design, performance testing and test results will be discussed.

Development of a Prototype Water Pump for Future Space Suit Applications

NASA Technical Reports Server (NTRS)

Hartman, David; Hodgson, Edward; Gervais, Edward, III; Trevino, Luis

2008-01-01

NASA s next generation of space suit systems will place new demands on the pump used to circulate cooling water through the life support system and the crew s liquid cooling garment. Long duration missions and frequent EVA require increased durability and reliability; limited resupply mass requirements demand compatibility with recycled water, and changing system design concepts demand increased tolerance for dissolved and free gas and the ability to operate over a broader range of flow rates and discharge pressure conditions. This paper describes the development of a positive displacement prototype pump to meet these needs. A gerotor based design has been adapted to meet pump performance, gas tolerance, and durability requirements while providing a small, lightweight pump assembly. This design has been detailed and implemented using materials selected to address anticipated water quality and mission needs as a prototype unit for testing in NASA laboratories. Design requirements, pump technology selection and design, performance testing and test results will be discussed.

Performance of the e2v 1.2 GPix cryogenic camera for the J-PAS 2.5m survey telescope

NASA Astrophysics Data System (ADS)

Robbins, M. S.; Bastable, M.; Bates, A.; Dryer, M.; Eames, S.; Fenemore-Jones, G.; Haddow, G.; Jorden, P. R.; Lane, B.; Marin-Franch, A.; Mortimer, J.; Palmer, I.; Puttay, N.; Renshaw, R.; Smith, M.; Taylor, K.; Tearle, J.; Weston, P.; Wheeler, P.; Worley, J.

2016-08-01

The J-PAS project will perform a five-year survey of the northern sky from a new 2.5m telescope in Teruel, Spain. In this paper the build and factory testing of the commercially supplied cryogenic camera is described. The 1.2 Giga-pixel focal plane is contained within a novel liquid-nitrogen cooled vacuum cryostat, which maintains the flatness for the cooled, 0.45m diameter focal plane to better than 27 μm peak to valley. The cooling system controls the focal plane to a temperature of -100°C with a variation across the focal plane of better than 2.5oC and a stability of better than +/- 0.5 °C over the long periods of operation required. The proximity drive electronics achieves total system level noise performance better than 5 e- from the 224-channel CCD system.

Optimized Heat Pipe Backup Cooling System Tested with a Stirling Convertor

NASA Technical Reports Server (NTRS)

Tarau, Calin; Schwendeman, Carl L.; Schifer, Nicholas A.; Anderson, William G.

2016-01-01

Advanced Stirling Radioisotope Generator (ASRG) is an attractive energy system for select space missions, and with the addition of a VCHP, it becomes even more versatile. The ASRG is powered through thermal energy from decaying radioisotopes acting as General Purpose Heat Sources (GPHS). A Stirling engine converts the thermal energy to electrical energy and cools the GPHS [2]. The Stirling convertor must operate continuously to maintain acceptable temperatures of the GPHS and protect their cladding. The addition of alkali metal VCHP allows the Stirling to cycle on and off during a mission and can be used as a backup cooling system. The benefits of being able to turn the Stirling off are: allowing for a restart of the Stirling and reducing vibrations for sensitive measurements. The VCHP addition should also increase the efficiency of the Stirling by providing a uniform temperature distribution at the heat transfer interface into the heater head.

A Thermal Physiological Comparison of Two HazMat Protective Ensembles With and Without Active Convective Cooling

NASA Technical Reports Server (NTRS)

Williamson, Rebecca; Carbo, Jorge; Luna, Bernadette; Webbon, Bruce W.

1998-01-01

Wearing impermeable garments for hazardous materials clean up can often present a health and safety problem for the wearer. Even short duration clean up activities can produce heat stress injuries in hazardous materials workers. It was hypothesized that an internal cooling system might increase worker productivity and decrease likelihood of heat stress injuries in typical HazMat operations. Two HazMat protective ensembles were compared during treadmill exercise. The different ensembles were created using two different suits: a Trelleborg VPS suit representative of current HazMat suits and a prototype suit developed by NASA engineers. The two life support systems used were a current technology Interspiro Spirolite breathing apparatus and a liquid air breathing system that also provided convective cooling. Twelve local members of a HazMat team served as test subjects. They were fully instrumented to allow a complete physiological comparison of their thermal responses to the different ensembles. Results showed that cooling from the liquid air system significantly decreased thermal stress. The results of the subjective evaluations of new design features in the prototype suit were also highly favorable. Incorporation of these new design features could lead to significant operational advantages in the future.

Performance and heat transfer characteristics of the laser-heated rocket - A future space transportation system

NASA Technical Reports Server (NTRS)

Shoji, J. M.; Larson, V. R.

1976-01-01

The application of advanced liquid-bipropellant rocket engine analysis techniques has been utilized for prediction of the potential delivered performance and the design of thruster wall cooling schemes for laser-heated rocket thrusters. Delivered specific impulse values greater than 1000 lbf-sec/lbm are potentially achievable based on calculations for thrusters designed for 10-kW and 5000-kW laser beam power levels. A thruster wall-cooling technique utilizing a combination of regenerative cooling and a carbon-seeded hydrogen boundary layer is presented. The flowing carbon-seeded hydrogen boundary layer provides radiation absorption of the heat radiated from the high-temperature plasma. Also described is a forced convection thruster wall cooling design for an experimental test thruster.

Thermosyphon Cooler Hybrid System for Water Savings in an Energy-Efficient HPC Data Center: Modeling and Installation: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, Thomas; Liu, Zan; Sickinger, David

The Thermosyphon Cooler Hybrid System (TCHS) integrates the control of a dry heat rejection device, the thermosyphon cooler (TSC), with an open cooling tower. A combination of equipment and controls, this new heat rejection system embraces the 'smart use of water,' using evaporative cooling when it is most advantageous and then saving water and modulating toward increased dry sensible cooling as system operations and ambient weather conditions permit. Innovative fan control strategies ensure the most economical balance between water savings and parasitic fan energy. The unique low-pressure-drop design of the TSC allows water to be cooled directly by the TSCmore » evaporator without risk of bursting tubes in subfreezing ambient conditions. Johnson Controls partnered with the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories to deploy the TSC as a test bed at NREL's high-performance computing (HPC) data center in the first half of 2016. Located in NREL's Energy Systems Integration Facility (ESIF), this HPC data center has achieved an annualized average power usage effectiveness rating of 1.06 or better since 2012. Warm-water liquid cooling is used to capture heat generated by computer systems direct to water; that waste heat is either reused as the primary heat source in the ESIF building or rejected using evaporative cooling. This data center is the single largest source of water and power demand on the NREL campus, using about 7,600 m3 (2.0 million gal) of water during the past year with an hourly average IT load of nearly 1 MW (3.4 million Btu/h) -- so dramatically reducing water use while continuing efficient data center operations is of significant interest. Because Sandia's climate is similar to NREL's, this new heat rejection system being deployed at NREL has gained interest at Sandia. Sandia's data centers utilize an hourly average of 8.5 MW (29 million Btu/h) and are also one of the largest consumers of water on Sandia's site. In addition to describing the installation of the TSC and its integration into the ESIF, this paper focuses on the full heat rejection system simulation program used for hourly analysis of the energy and water consumption of the complete system under varying operating scenarios. A follow-up paper will detail the test results. The evaluation of the TSC's performance at NREL will also determine a path forward at Sandia for possible deployment in a large-scale system not only for data center use but also possibly site wide.« less

Implementation of a Legionella Ordinance for Multifamily Housing, Garland, Texas

PubMed Central

Whitney, Ellen A.; Blake, Sarah

2017-01-01

Context: The incidence of legionellosis has sharply increased in the United States as a result of contaminated water systems. Jurisdictions across the country are considering whether to develop and implement regulations to protect individuals against Legionnaires' disease with its associated high morbidity and mortality. Objective: This article sheds light on the implementation and effectiveness of a 2005 citywide Legionella testing mandate of multifamily housing cooling towers in Garland, Texas. This ordinance has been in place for more than 10 years and represents the first of its kind in the United States to mandate routine testing of cooling towers for Legionella in multifamily housing. Design, Setting, and Population: We utilized a mix of both qualitative and quantitative methods to explore the development, adoption, and implementation of the ordinance. Phone interviews were conducted with individuals from the City of Garland Health Department and apartment managers. Quantitative data included public health surveillance data on legionellosis. Main Outcome Measures: Barriers and facilitators of implementation, number and percentage of cooling towers from multifamily housing units that tested positive for Legionella by year, and number of legionellosis cases by year in Garland, Texas. Results: Study outcomes highlight key themes that facilitated the successful implementation of the Legionella testing mandate, including the importance of timing, leadership support, stakeholder engagement, and education and outreach. The number of contaminated cooling towers was reduced over time. Conclusion: Mandatory monitoring for legionella in a local jurisdiction may result in reduced risk of legionellosis from cooling towers through raising awareness and education of building owners and managers about the need to prevent, detect, and remediate legionella contamination in their building water systems. Garland, Texas, broke new ground in the United States in moving toward primary prevention of legionellosis. The ordinance may be useful both in serving to educate and increase awareness about the need for Legionella prevention and to monitor effectiveness of maintenance procedures. PMID:28141673

Development, testing, and certification of Calmac Mfg. Corp. solar collector and solar operated pump

NASA Technical Reports Server (NTRS)

Parker, J. C.

1979-01-01

Development of a rubber tube solar collector and solar operated pump for use with solar heating and cooling systems is discussed. The development hardware, problems encountered during fabrication and testing, and certification statements of performance are included.

SHUTTLE - ASTRONAUT-CANDIDATE (ASCAN) WILLIAMS, DONALD (DON)

NASA Image and Video Library

1979-04-03

S79-30367/69: Exterior views of 747 Shuttle Aircraft. S79-30360/66: ASCAN Don Williams during H Reflex Studies and Hamilton-Standard Tool Belt and Suit Cooling System Tests. 1. AIRCRAFT - 747 2. SHUTTLE - TESTS. S79-30360 thru S79-30369

Raytheon RSP2 Cryocooler Low Temperature Testing and Design Enhancements

NASA Astrophysics Data System (ADS)

Hon, R. C.; Kirkconnell, C. S.; Shrago, J. A.

2010-04-01

The High Capacity Raytheon Stirling/Pulse Tube Hybrid 2-Stage cryocooler (HC-RSP2) was originally developed to provide simultaneous cooling at temperatures of 85 K and 35 K. During testing performed in 2008 it was demonstrated that this stock-configuration cryocooler is capable of providing significant amounts of heat lift at 2nd stage temperatures as low as 12 K, and modeling indicated that minor changes to the 2nd stage inertance tube/surge volume setup could yield improved performance. These changes were implemented and the cooler was successfully retested, producing >350 mW of heat lift at 12 K. A comprehensive redesign of the system has been performed, the result of which is a robust 2-stage cryocooler system that is intended to efficiently produce relatively large amounts of cooling at 2nd stage temperatures <12 K. This cryocooler, called the Low Temperature RSP2 (LT-RSP2) will be fabricated and tested over the next 12 months. This paper reports on the recently-completed test activities, as well as details relating to the system redesign. Expected performance, mass and packaging volume are addressed.

Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

NASA Technical Reports Server (NTRS)

Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 C temperature increase from the nominal vapor temperature. The 19 C temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental results from integrating the VCHP with an operating Stirling convertor and describes the methodology used to achieve their successful combined operation.

Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

NASA Technical Reports Server (NTRS)

Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental results from integrating the VCHP with an operating Stirling convertor and describes the methodology used to achieve their successful combined operation.

40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

Cooling Technology for Large Space Telescopes

NASA Technical Reports Server (NTRS)

DiPirro, Michael; Cleveland, Paul; Durand, Dale; Klavins, Andy; Muheim, Daniella; Paine, Christopher; Petach, Mike; Tenerelli, Domenick; Tolomeo, Jason; Walyus, Keith

2007-01-01

NASA's New Millennium Program funded an effort to develop a system cooling technology, which is applicable to all future infrared, sub-millimeter and millimeter cryogenic space telescopes. In particular, this technology is necessary for the proposed large space telescope Single Aperture Far-Infrared Telescope (SAFIR) mission. This technology will also enhance the performance and lower the risk and cost for other cryogenic missions. The new paradigm for cooling to low temperatures will involve passive cooling using lightweight deployable membranes that serve both as sunshields and V-groove radiators, in combination with active cooling using mechanical coolers operating down to 4 K. The Cooling Technology for Large Space Telescopes (LST) mission planned to develop and demonstrate a multi-layered sunshield, which is actively cooled by a multi-stage mechanical cryocooler, and further the models and analyses critical to scaling to future missions. The outer four layers of the sunshield cool passively by radiation, while the innermost layer is actively cooled to enable the sunshield to decrease the incident solar irradiance by a factor of more than one million. The cryocooler cools the inner layer of the sunshield to 20 K, and provides cooling to 6 K at a telescope mounting plate. The technology readiness level (TRL) of 7 will be achieved by the active cooling technology following the technology validation flight in Low Earth Orbit. In accordance with the New Millennium charter, tests and modeling are tightly integrated to advance the technology and the flight design for "ST-class" missions. Commercial off-the-shelf engineering analysis products are used to develop validated modeling capabilities to allow the techniques and results from LST to apply to a wide variety of future missions. The LST mission plans to "rewrite the book" on cryo-thermal testing and modeling techniques, and validate modeling techniques to scale to future space telescopes such as SAFIR.

Application of solar energy; Proceedings of the Third Southeastern Conference, Huntsville, Ala., April 17-19, 1978

NASA Technical Reports Server (NTRS)

Wu, S. T. (Editor); Christensen, D. L.; Head, R. R.

1978-01-01

Demonstration projects, systems-subsystems simulation programs, applications (heating, cooling, agricultural, industrial), and climatic data testing (standards, economics, institutional) are the topics of the book. Economics of preheating water for commercial use and collecting, processing, and dissemination of data for the national demonstration program are discussed. Computer simulation of a solar energy system and graphical representation of solar collector performance are considered. Attention is given to solar driven heat pumps, solar cooling equipment, hybrid passive/active solar systems, and solar farm buildings. Evaluation of a thermographic scanning device for solar energy and conservation applications, use of meteorological data in system evaluation, and biomass conversion potential are presented.

A continuous dry 300 mK cooler for THz sensing applications.

PubMed

Klemencic, G M; Ade, P A R; Chase, S; Sudiwala, R; Woodcraft, A L

2016-04-01

We describe and demonstrate the automated operation of a novel cryostat design that is capable of maintaining an unloaded base temperature of less than 300 mK continuously, without the need to recycle the gases within the final cold head, as is the case for conventional single shot sorption pumped (3)He cooling systems. This closed dry system uses only 5 l of (3)He gas, making this an economical alternative to traditional systems where a long hold time is required. During testing, a temperature of 365 mK was maintained with a constant 20 μW load, simulating the cooling requirement of a far infrared camera.

Effects of cooling system parameters on heat transfer in PAFC stack. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Abdul-Aziz, Ali A.

1985-01-01

Analytical and experimental study for the effects of cooling system parameters on the heat transfer and temperature distribution in the electrode plates of a phosphoric acid fuel-cell has been conducted. An experimental set-up that simulates the operating conditions prevailing in a phosphoric-acid fuel-cell stack was designed and constructed. The set-up was then used to measure the overall heat transfer coefficient, the thermal contact resistance, and the electrode temperature distribution for two different cooling plate configurations. Two types of cooling plate configurations, serpentine and straight, were tested. Air, water, and oil were used as coolants. Measurements for the heat transfer coefficient and the thermal contact resistance were made for various flow rates ranging from 16 to 88 Kg/hr, and stack clamping pressure ranging from O to 3448 Kpa. The experimental results for the overall heat transfer coefficient were utilized to derive mathematical relations for the overall heat transfer coefficient as a function of stack clamping pressure and Reynolds number for the three coolants. The empirically derived formulas were incorporated in a previously developed computer program to predict electrodes temperature distribution and the performance of the stack cooling system. The results obtained were then compared with those available in the literature. The comparison showed maximum deviation of +/- 11%.

30 CFR 7.102 - Exhaust gas cooling efficiency test.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Exhaust gas cooling efficiency test. 7.102 Section 7.102 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING....102 Exhaust gas cooling efficiency test. (a) Test procedures. (1) Follow the procedures specified in...

Testing of a Neon Loop Heat Pipe for Large Area Cryocooling

NASA Technical Reports Server (NTRS)

Ku, Jentung; Robinson, Franklin Lee

2014-01-01

Cryocooling of large areas such as optics, detector arrays, and cryogenic propellant tanks is required for future NASA missions. A cryogenic loop heat pipe (CLHP) can provide a closed-loop cooling system for this purpose and has many advantages over other devices in terms of reduced mass, reduced vibration, high reliability, and long life. A neon CLHP was tested extensively in a thermal vacuum chamber using a cryopump as the heat sink to characterize its transient and steady performance and verify its ability to cool large areas or components. Tests conducted included loop cool-down from the ambient temperature, startup, power cycle, heat removal capability, loop capillary limit and recovery from a dry-out, low power operation, and long duration steady state operation. The neon CLHP demonstrated robust operation. The loop could be cooled from the ambient temperature to subcritical temperatures very effectively, and could start successfully by applying power to both the pump and evaporator without any pre-conditioning. It could adapt to changes in the pump power andor evaporator power, and reach a new steady state very quickly. The evaporator could remove heat loads between 0.25W and 4W. When the pump capillary limit was exceeded, the loop could resume its normal function by reducing the pump power. Steady state operations were demonstrated for up to 6 hours. The ability of the neon loop to cool large areas was therefore successfully verified.

Effects of system size and cooling rate on the structure and properties of sodium borosilicate glasses from molecular dynamics simulations.

PubMed

Deng, Lu; Du, Jincheng

2018-01-14

Borosilicate glasses form an important glass forming system in both glass science and technologies. The structure and property changes of borosilicate glasses as a function of thermal history in terms of cooling rate during glass formation and simulation system sizes used in classical molecular dynamics (MD) simulation were investigated with recently developed composition dependent partial charge potentials. Short and medium range structural features such as boron coordination, Si and B Q n distributions, and ring size distributions were analyzed to elucidate the effects of cooling rate and simulation system size on these structure features and selected glass properties such as glass transition temperature, vibration density of states, and mechanical properties. Neutron structure factors, neutron broadened pair distribution functions, and vibrational density of states were calculated and compared with results from experiments as well as ab initio calculations to validate the structure models. The results clearly indicate that both cooling rate and system size play an important role on the structures of these glasses, mainly by affecting the 3 B and 4 B distributions and consequently properties of the glasses. It was also found that different structure features and properties converge at different sizes or cooling rates; thus convergence tests are needed in simulations of the borosilicate glasses depending on the targeted properties. The results also shed light on the complex thermal history dependence on structure and properties in borosilicate glasses and the protocols in MD simulations of these and other glass materials.

Effects of system size and cooling rate on the structure and properties of sodium borosilicate glasses from molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Deng, Lu; Du, Jincheng

2018-01-01

Borosilicate glasses form an important glass forming system in both glass science and technologies. The structure and property changes of borosilicate glasses as a function of thermal history in terms of cooling rate during glass formation and simulation system sizes used in classical molecular dynamics (MD) simulation were investigated with recently developed composition dependent partial charge potentials. Short and medium range structural features such as boron coordination, Si and B Qn distributions, and ring size distributions were analyzed to elucidate the effects of cooling rate and simulation system size on these structure features and selected glass properties such as glass transition temperature, vibration density of states, and mechanical properties. Neutron structure factors, neutron broadened pair distribution functions, and vibrational density of states were calculated and compared with results from experiments as well as ab initio calculations to validate the structure models. The results clearly indicate that both cooling rate and system size play an important role on the structures of these glasses, mainly by affecting the 3B and 4B distributions and consequently properties of the glasses. It was also found that different structure features and properties converge at different sizes or cooling rates; thus convergence tests are needed in simulations of the borosilicate glasses depending on the targeted properties. The results also shed light on the complex thermal history dependence on structure and properties in borosilicate glasses and the protocols in MD simulations of these and other glass materials.

Helium heater design for the helium direct cycle component test facility. [for gas-cooled nuclear reactor power plant

NASA Technical Reports Server (NTRS)

Larson, V. R.; Gunn, S. V.; Lee, J. C.

1975-01-01

The paper describes a helium heater to be used to conduct non-nuclear demonstration tests of the complete power conversion loop for a direct-cycle gas-cooled nuclear reactor power plant. Requirements for the heater include: heating the helium to a 1500 F temperature, operating at a 1000 psia helium pressure, providing a thermal response capability and helium volume similar to that of the nuclear reactor, and a total heater system helium pressure drop of not more than 15 psi. The unique compact heater system design proposed consists of 18 heater modules; air preheaters, compressors, and compressor drive systems; an integral control system; piping; and auxiliary equipment. The heater modules incorporate the dual-concentric-tube 'Variflux' heat exchanger design which provides a controlled heat flux along the entire length of the tube element. The heater design as proposed will meet all system requirements. The heater uses pressurized combustion (50 psia) to provide intensive heat transfer, and to minimize furnace volume and heat storage mass.

Compressor bleed cooling fluid feed system

DOEpatents

Donahoo, Eric E; Ross, Christopher W

2014-11-25

A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

14 CFR 29.1049 - Hovering cooling test procedures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... minutes after the occurrence of the highest temperature recorded; and (b) With maximum continuous power... five minutes after the occurrence of the highest temperature recorded. Induction System ...

14 CFR 29.1049 - Hovering cooling test procedures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... minutes after the occurrence of the highest temperature recorded; and (b) With maximum continuous power... five minutes after the occurrence of the highest temperature recorded. Induction System ...

14 CFR 29.1049 - Hovering cooling test procedures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... minutes after the occurrence of the highest temperature recorded; and (b) With maximum continuous power... five minutes after the occurrence of the highest temperature recorded. Induction System ...

14 CFR 29.1049 - Hovering cooling test procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... minutes after the occurrence of the highest temperature recorded; and (b) With maximum continuous power... five minutes after the occurrence of the highest temperature recorded. Induction System ...

14 CFR 29.1049 - Hovering cooling test procedures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... minutes after the occurrence of the highest temperature recorded; and (b) With maximum continuous power... five minutes after the occurrence of the highest temperature recorded. Induction System ...

BETA (Bitter Electromagnet Testing Apparatus) Design and Testing

NASA Astrophysics Data System (ADS)

Bates, Evan; Birmingham, William; Rivera, William; Romero-Talamas, Carlos

2016-10-01

BETA is a 1T water cooled Bitter-type magnetic system that has been designed and constructed at the Dusty Plasma Laboratory of the University of Maryland, Baltimore County to serve as a prototype of a scaled 10T version. Currently the system is undergoing magnetic, thermal and mechanical testing to ensure safe operating conditions and to prove analytical design optimizations. These magnets will function as experimental tools for future dusty plasma based and collaborative experiments. An overview of design methods used for building a custom made Bitter magnet with user defined experimental constraints is reviewed. The three main design methods consist of minimizing the following: ohmic power, peak conductor temperatures, and stresses induced by Lorentz forces. We will also discuss the design of BETA which includes: the magnet core, pressure vessel, cooling system, power storage bank, high powered switching system, diagnostics with safety cutoff feedback, and data acquisition (DAQ)/magnet control Matlab code. Furthermore, we present experimental data from diagnostics for validation of our analytical preliminary design methodologies and finite element analysis calculations. BETA will contribute to the knowledge necessary to finalize the 10 T magnet design.

AUTOMOTIVE DIESEL MAINTENACE 1. UNIT XV, I--MAINTAINING THE COOLING SYSTEM, CUMMINS DIESEL ENGINE, I--UNIT INSTALLATION--TRANSMISSION.

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE FUNCTION AND MAINTENANCE OF THE DIESEL ENGINE COOLING SYSTEM AND THE PROCEDURES FOR TRANSMISSION INSTALLATION. TOPICS ARE (1) IMPORTANCE OF THE COOLING SYSTEM, (2) COOLING SYSTEM COMPONENTS, (3) EVALUATING COOLING SYSTEM FAILURES, (4) CARING FOR THE COOLING SYSTEM,…

Simplified Space Conditioning in Low-Load Homes: Results from Pittsburgh, Pennsylvania, New Construction Unoccupied Test House

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poerschke, A.; Stecher, D.

2014-06-01

Field testing was performed in a new construction unoccupied test house in Pittsburgh, Pennsylvania. Four air-based heating, ventilation, and air conditioning distribution systems--a typical airflow ducted system to the bedrooms, a low airflow ducted system to the bedrooms, a system with transfer fans to the bedrooms, and a system with no ductwork to the bedrooms--were evaluated during heating, cooling, and midseason conditions. The relative ability of each system was assessed with respect to relevant Air Conditioning Contractors of America and ASHRAE standards for house temperature uniformity and stability, respectively.

Preoperational test report, recirculation ventilation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clifton, F.T.

1997-11-11

This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

In-orbit performance of a helium dewar for the soft X-ray spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Yoshida, Seiji; Miyaoka, Mikio; Kanao, Ken'ichi; Tsunematsu, Shoji; Otsuka, Kiyomi; Hoshika, Shunji; Narasaki, Katsuhiro; Mitsuda, Kazuhisa; Yamasaki, Noriko; Takei, Yoh; Fujimoto, Ryuichi; Ezoe, Yuichiro; Sato, Yoichi; Okamoto, Atsushi; Noda, Hirofumi; DiPirro, Michael; Shirron, Peter

2018-04-01

ASTRO-H was an X-ray astronomy satellite that the Japan Aerospace Exploration Agency (JAXA) developed to study the evolution of the universe and physical phenomena yet to be discovered. The primary scientific instrument of ASTRO-H was the Soft X-ray Spectrometer (SXS). Its detectors were to be cooled to 50 m K using a complex cryogenic system with a multistage adiabatic demagnetization refrigerator (ADR) developed by the National Aeronautics and Space Administration (NASA), and a cryogenic system developed by Sumitomo Heavy Industries, Ltd. (SHI). SHI's cryogenic system was required to cool the ADR's heatsink to 1.3 K or less in orbit for three years or longer. To meet these requirements, SHI developed a hybrid cryogenic system consisting of a liquid helium tank, a 4 K Joule-Thomson cooler, and two two-stage Stirling coolers. ASTRO-H was launched from Tanegashima Space Center on February 17, 2016. The initial operation of the SXS cryogenic system in orbit was completed successfully. The cooling performance was as expected and could have exceeded the lifetime requirement of three years. This paper describes results of ground tests, results of top-off filling of superfluid liquid helium just before launch, and cooling performance in orbit.

A Heat Transfer Investigation of Liquid and Two-Phase Methane

NASA Technical Reports Server (NTRS)

VanNoord, Jonathan

2010-01-01

A heat transfer investigation was conducted for liquid and two-phase methane. The tests were conducted at the NASA Glenn Research Center Heated Tube Facility (HTF) using resistively heated tube sections to simulate conditions encountered in regeneratively cooled rocket engines. This testing is part of NASA s Propulsion and Cryogenics Advanced Development (PCAD) project. Nontoxic propellants, such as liquid oxygen/liquid methane (LO2/LCH4), offer potential benefits in both performance and safety over equivalently sized hypergolic propulsion systems in spacecraft applications. Regeneratively cooled thrust chambers are one solution for high performance, robust LO2/LCH4 engines, but cooling data on methane is limited. Several test runs were conducted using three different diameter Inconel 600 tubes, with nominal inner diameters of 0.0225-, 0.054-, and 0.075-in. The mass flow rate was varied from 0.005 to 0.07 lbm/sec. As the current focus of the PCAD project is on pressure fed engines for LO2/LCH4, the average test section outlet pressures were targeted to be 200 psia or 500 psia. The heat flux was incrementally increased for each test condition while the test section wall temperatures were monitored. A maximum average heat flux of 6.2 Btu/in.2 sec was achieved and, at times, the temperatures of the test sections reached in excess of 1800 R. The primary objective of the tests was to produce heat transfer correlations for methane in the liquid and two-phase regime. For two-phase flow testing, the critical heat flux values were determined where the fluid transitions from nucleate boiling to film boiling. A secondary goal of the testing was to measure system pressure drops in the two-phase regime.

Development of a Split Bitter-type Magnet System for Dusty Plasma Experiments

NASA Astrophysics Data System (ADS)

Bates, Evan; Romero-Talamas, Carlos A.; Birmingham, William J.; Rivera, William F.

2014-10-01

A 10 Tesla Bitter-type magnetic system is under development at the Dusty Plasma Laboratory of the University of Maryland, Baltimore County (UMBC). We present here an optimization technique that uses differential evolution to minimize the omhic heating produced by the coils, while constraining the magnetic field in the experimental volume. The code gives us the optimal dimensions for the coil system including: coil length, turn thickness, disks radii, resistance, and total current required for a constant magnetic field. Finite element parametric optimization is then used to establish the optimal design for water cooling holes. Placement of the cooling holes will also take into consideration the magnetic forces acting on the copper alloy disks to ensure the material strength is not compromised during operation. The proposed power and cooling water delivery subsystems for the coils are also presented. Upon completion and testing of the magnet system, planned experiments include the propagation of magnetized waves in dusty plasma crystals under various boundary conditions, and viscosity in rotational shear flow, among others.

idRHa+ProMod - Rail Hardening Control System

NASA Astrophysics Data System (ADS)

Ferro, L.

2016-03-01

idRHa+ProMod is the process control system developed by Primetals Technologies to foresee the thermo-mechanical evolution and micro-structural composition of rail steels subjected to slack quenching into idRHa+ Rail Hardening equipments in a simulation environment. This tool can be used both off-line or in-line, giving the user the chance to test and study the best cooling strategies or letting the automatic control system free to adjust the proper cooling recipe. Optimization criteria have been tailored in order to determine the best cooling conditions according to the metallurgical requirements imposed by the main rail standards and also taking into account the elastoplastic bending phenomena occurring during all stages of the head hardening process. The computational core of idRHa+ProMod is a thermal finite element procedure coupled with special algorithms developed to work out the main thermo-physical properties of steel, to predict the non-isothermal austenite decomposition into all the relevant phases and subsequently to evaluate the amount of latent heat of transformation released, the compound thermal expansion coefficient and the amount of plastic deformation in the material. Air mist and air blades boundary conditions have been carefully investigated by means of pilot plant tests aimed to study the jet impingement on rail surfaces and the cooling efficiency at all working conditions. Heat transfer coefficients have been further checked and adjusted directly on field during commissioning. idRHa+ is a trademark of Primetals Technologies Italy Srl

Study on Circular Complex viewed from Environmental Systems

NASA Astrophysics Data System (ADS)

Takeguchi, Tomoo; Adachi, Katsushige; Yoshikawa, Akira; Hiratsuka, Akira; Tsujino, Ryoji; Iguchi, Manabu

In machining processes, cutting fluids are generally used for cooling and lubricating workpieces at the point cutting. However, these fluids frequently include chlorine, sulfur, phosphorus, or other additives. The chemicals not only become a mist affecting the health of workers engaged in the processing but also make the workshop environment worse. In particular, the chlorine becomes one of the causes of global warming by treating waste oil under high temperature conditions. It is furthermore said that huge cost beyond the purchase cost of oil occurs and dioxins (carcinogen) usually exist in the waste oil. Therefore, an environmentally-friendly cooling-air cutting system is required from the standpoint of green manufacturing. This system has been noted as a technique to solve the issues against the environment mentioned above. In the cooling-air cutting processing, the amount of CO2 emission shows a low value compared with the dry cutting one which uses oil. It is therefore thought that the cooling-air cutting system is a very important processing technique as an environmental countermeasure. At present, in strictly economic and environmental situations, the compatibility of the betterment of production efficiency with the improvement of environment is a subject in the actual spot of a cut processing. This study deals with the test results of cooling-air drilling performance from the viewpoint of taking green manufacturing into account. The workpiece made of die steel SKDll was manufactured by the cooling-air drilling performance at a revolution of 840 rpm and a temperature of -20°C with a high-speed steel drill (SKH56). The results were compared with those for the dry cutting performance. The main results obtained in this study are as follows: 1) The tool life for cooling-air drilling performance was about 6 times as long as that for the dry cutting performance. 2) The chip temperature for cooling-air drilling was 220°C lower than that for the dry cutting performance.

Reduced Boil-Off System Sizing

NASA Technical Reports Server (NTRS)

Guzik, Monica C.; Plachta, David W.; Feller, Jeffrey R.

2015-01-01

NASA is currently developing cryogenic propellant storage and transfer systems for future space exploration and scientific discovery missions by addressing the need to raise the technology readiness level of cryogenic fluid management technologies. Cryogenic propellants are baselined in many propulsion systems due to their inherently high specific impulse; however, their low boiling points can cause substantial boil-off losses over time. Recent efforts such as the Reduced Boil-off Testing and the Active Thermal Control Scaling Study provide important information on the benefit of an active cooling system applied to LH2 propellant storage. Findings show that zero-boil off technologies can reduce overall mass in LH2 storage systems when low Earth orbit loiter periods extend beyond two months. A significant part of this mass reduction is realized by integrating two stages of cooling: a 20 K stage to intercept heat at the tank surface, and a 90 K stage to reduce the heat entering the less efficient 20 K stage. A missing element in previous studies, which is addressed in this paper, is the development of a direct method for sizing the 90 K cooling stage. Such a method requires calculation of the heat entering both the 90 K and 20 K stages as compared to the overall system masses, and is reliant upon the temperature distribution, performance, and unique design characteristics of the system in question. By utilizing the known conductance of a system without active thermal control, the heat being intercepted by a 90 K stage can be calculated to find the resultant lift and mass of each active thermal control stage. Integral to this is the thermal conductance of the cooling straps and the broad area cooling shield, key parts of the 90 K stage. Additionally, a trade study is performed to show the ability of the 90 K cooling stage to reduce the lift on the 20 K cryocooler stage, which is considerably less developed and efficient than 90 K cryocoolers.

Split radiator design for heat rejection optimization for a waste heat recovery system

DOEpatents

Ernst, Timothy C.; Nelson, Christopher R.

2016-10-18

A cooling system provides improved heat recovery by providing a split core radiator for both engine cooling and condenser cooling for a Rankine cycle (RC). The cooling system includes a radiator having a first cooling core portion and a second cooling core portion. An engine cooling loop is fluidly connected the second cooling core portion. A condenser of an RC has a cooling loop fluidly connected to the first cooling core portion. A valve is provided between the engine cooling loop and the condenser cooling loop adjustably control the flow of coolant in the condenser cooling loop into the engine cooling loop. The cooling system includes a controller communicatively coupled to the valve and adapted to determine a load requirement for the internal combustion engine and adjust the valve in accordance with the engine load requirement.

Variable Conductance Heat Pipe Cooling of Stirling Convertor and General Purpose Heat Source

NASA Technical Reports Server (NTRS)

Tarau, Calin; Schwendeman, Carl; Anderson William G.; Cornell, Peggy A.; Schifer, Nicholas A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental results from integrating the VCHP with an operating Stirling convertor and describes the methodology used to achieve their successful combined operation.

Wave-optics modeling of the optical-transport line for passive optical stochastic cooling

NASA Astrophysics Data System (ADS)

Andorf, M. B.; Lebedev, V. A.; Piot, P.; Ruan, J.

2018-03-01

Optical stochastic cooling (OSC) is expected to enable fast cooling of dense particle beams. Transition from microwave to optical frequencies enables an achievement of stochastic cooling rates which are orders of magnitude higher than ones achievable with the classical microwave based stochastic cooling systems. A subsystemcritical to the OSC scheme is the focusing optics used to image radiation from the upstream "pickup" undulator to the downstream "kicker" undulator. In this paper, we present simulation results using wave-optics calculation carried out with the SYNCHROTRON RADIATION WORKSHOP (SRW). Our simulations are performed in support to a proof-of-principle experiment planned at the Integrable Optics Test Accelerator (IOTA) at Fermilab. The calculations provide an estimate of the energy kick received by a 100-MeV electron as it propagates in the kicker undulator and interacts with the electromagnetic pulse it radiated at an earlier time while traveling through the pickup undulator.

Active cooling of microvascular composites for battery packaging

NASA Astrophysics Data System (ADS)

Pety, Stephen J.; Chia, Patrick X. L.; Carrington, Stephen M.; White, Scott R.

2017-10-01

Batteries in electric vehicles (EVs) require a packaging system that provides both thermal regulation and crash protection. A novel packaging scheme is presented that uses active cooling of microvascular carbon fiber reinforced composites to accomplish this multifunctional objective. Microvascular carbon fiber/epoxy composite panels were fabricated and their cooling performance assessed over a range of thermal loads and experimental conditions. Tests were performed for different values of coolant flow rate, channel spacing, panel thermal conductivity, and applied heat flux. More efficient cooling occurs when the coolant flow rate is increased, channel spacing is reduced, and thermal conductivity of the host composite is increased. Computational fluid dynamics (CFD) simulations were also performed and correlate well with the experimental data. CFD simulations of a typical EV battery pack confirm that microvascular composite panels can adequately cool battery cells generating 500 W m-2 heat flux below 40 °C.

Performance comparison investigation on solar photovoltaic-thermoelectric generation and solar photovoltaic-thermoelectric cooling hybrid systems under different conditions

NASA Astrophysics Data System (ADS)

Wu, Shuang-Ying; Zhang, Yi-Chen; Xiao, Lan; Shen, Zu-Guo

2018-07-01

The performance of solar photovoltaic-thermoelectric generation hybrid system (PV-TGS) and solar photovoltaic-thermoelectric cooling hybrid system (PV-TCS) under different conditions were theoretically analysed and compared. To test the practicality of these two hybrid systems, the performance of stand-alone PV system was also studied. The results show that PV-TGS and PV-TCS in most cases will result in the system with a better performance than stand-alone PV system. The advantage of PV-TGS is emphasised in total output power and conversion efficiency which is even poorer in PV-TCS than that in stand-alone PV system at the ambient wind speed uw being below 3 m/s. However, PV-TCS has obvious advantage on lowering the temperature of PV cell. There is an obvious increase in tendency on the performance of PV-TGS and PV-TCS when the cooling capacity of two hybrid systems varies from around 0.06 to 0.3 W/K. And it is also proved that not just a-Si in PV-TGS can produce a better performance than the stand-alone PV system alone at most cases.

Quiet Clean Short-haul Experimental Engine (QCSEE). Under-The-Wing (UTW) engine boilerplate nacelle test report. Volume 3: Mechanical performance

NASA Technical Reports Server (NTRS)

1977-01-01

Results of initial tests of the under the wing experimental engine and boilerplate nacelle are presented. The mechanical performance of the engine is reported with emphasis on the advanced technology components. Technology elements of the propulsion system covered include: system dynamics, composite fan blades, reduction gear, lube and accessory drive system, fan frame, inlet, core cowl cooling, fan exhaust nozzle, and digital control system.

Comparisons of RELAP5-3D Analyses to Experimental Data from the Natural Convection Shutdown Heat Removal Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bucknor, Matthew; Hu, Rui; Lisowski, Darius

2016-04-17

The Reactor Cavity Cooling System (RCCS) is an important passive safety system being incorporated into the overall safety strategy for high temperature advanced reactor concepts such as the High Temperature Gas- Cooled Reactors (HTGR). The Natural Convection Shutdown Heat Removal Test Facility (NSTF) at Argonne National Laboratory (Argonne) reflects a 1/2-scale model of the primary features of one conceptual air-cooled RCCS design. The project conducts ex-vessel, passive heat removal experiments in support of Department of Energy Office of Nuclear Energy’s Advanced Reactor Technology (ART) program, while also generating data for code validation purposes. While experiments are being conducted at themore » NSTF to evaluate the feasibility of the passive RCCS, parallel modeling and simulation efforts are ongoing to support the design, fabrication, and operation of these natural convection systems. Both system-level and high fidelity computational fluid dynamics (CFD) analyses were performed to gain a complete understanding of the complex flow and heat transfer phenomena in natural convection systems. This paper provides a summary of the RELAP5-3D NSTF model development efforts and provides comparisons between simulation results and experimental data from the NSTF. Overall, the simulation results compared favorably to the experimental data, however, further analyses need to be conducted to investigate any identified differences.« less

PILOT-SCALE REMOVAL OF FLUORIDE FROM LEGACY PLUTONIUM MATERIALS USING VACUUM SALT DISTILLATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, R. A.; Pak, D. J.

2012-09-11

Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. In 2011, SRNL adapted the technology for the removal of fluoride from fluoride-bearing salts. The method involved an in situ reaction between potassium hydroxide (KOH) and the fluoride salt to yield potassium fluoride (KF) and the corresponding oxide. The KF and excess KOH can be distilled below 1000{deg}C using vacuum salt distillation (VSD). The apparatus for vacuum distillation contains a zone heated by a furnace and a zone actively cooled using eithermore » recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attaned, heating begins. Volatile salts distill from the heated zone to the cooled zone where they condense, leaving behind the non-volatile material in the feed boat. Studies discussed in this report were performed involving the use of non-radioactive simulants in small-scale and pilot-scale systems as well as radioactive testing of a small-scale system with plutonium-bearing materials. Aspects of interest include removable liner design considerations, boat materials, in-line moisture absorption, and salt deposition.« less

Advanced diesel electronic fuel injection and turbocharging

NASA Astrophysics Data System (ADS)

Beck, N. J.; Barkhimer, R. L.; Steinmeyer, D. C.; Kelly, J. E.

1993-12-01

The program investigated advanced diesel air charging and fuel injection systems to improve specific power, fuel economy, noise, exhaust emissions, and cold startability. The techniques explored included variable fuel injection rate shaping, variable injection timing, full-authority electronic engine control, turbo-compound cooling, regenerative air circulation as a cold start aid, and variable geometry turbocharging. A Servojet electronic fuel injection system was designed and manufactured for the Cummins VTA-903 engine. A special Servojet twin turbocharger exhaust system was also installed. A series of high speed combustion flame photos was taken using the single cylinder optical engine at Michigan Technological University. Various fuel injection rate shapes and nozzle configurations were evaluated. Single-cylinder bench tests were performed to evaluate regenerative inlet air heating techniques as an aid to cold starting. An exhaust-driven axial cooling air fan was manufactured and tested on the VTA-903 engine.

Controlled cooling of an electronic system based on projected conditions

DOEpatents

David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

2016-05-17

Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

Controlled cooling of an electronic system based on projected conditions

DOEpatents

David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

2015-08-18

Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

A Synergistic Combination of Advanced Separation and Chemical Scale Inhibitor Technologies for Efficient Use of Imparied Water As Cooling Water in Coal-based Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jasbir Gill

2010-08-30

Nalco Company is partnering with Argonne National Laboratory (ANL) in this project to jointly develop advanced scale control technologies that will provide cost-effective solutions for coal-based power plants to operate recirculating cooling water systems at high cycles using impaired waters. The overall approach is to use combinations of novel membrane separations and scale inhibitor technologies that will work synergistically, with membrane separations reducing the scaling potential of the cooling water and scale inhibitors extending the safe operating range of the cooling water system. The project started on March 31, 2006 and ended in August 30, 2010. The project was amore » multiyear, multi-phase project with laboratory research and development as well as a small pilot-scale field demonstration. In Phase 1 (Technical Targets and Proof of Concept), the objectives were to establish quantitative technical targets and develop calcite and silica scale inhibitor chemistries for high stress conditions. Additional Phase I work included bench-scale testing to determine the feasibility of two membrane separation technologies (electrodialysis ED and electrode-ionization EDI) for scale minimization. In Phase 2 (Technology Development and Integration), the objectives were to develop additional novel scale inhibitor chemistries, develop selected separation processes, and optimize the integration of the technology components at the laboratory scale. Phase 3 (Technology Validation) validated the integrated system's performance with a pilot-scale demonstration. During Phase 1, Initial evaluations of impaired water characteristics focused on produced waters and reclaimed municipal wastewater effluents. Literature and new data were collected and evaluated. Characteristics of produced waters vary significantly from one site to another, whereas reclaimed municipal wastewater effluents have relatively more uniform characteristics. Assessment to date confirmed that calcite and silica/silicate are two common potential cycle-limiting minerals for using impaired waters. For produced waters, barium sulfate and calcium sulfate are two additional potential cycle-limiting minerals. For reclaimed municipal wastewater effluents, calcium phosphate scaling can be an issue, especially in the co-presence of high silica. Computational assessment, using a vast amount of Nalco's field data from coal fired power plants, showed that the limited use and reuse of impaired waters is due to the formation of deposit caused by the presence of iron, high hardness, high silica and high alkalinity in the water. Appropriate and cost-effective inhibitors were identified and developed - LL99B0 for calcite and gypsum inhibition and TX-15060 for silica inhibition. Nalco's existing dispersants HSP-1 and HSP-2 has excellent efficacy for dispersing Fe and Mn. ED and EDI were bench-scale tested by the CRADA partner Argonne National Laboratory for hardness, alkalinity and silica removal from synthetic make-up water and then cycled cooling water. Both systems showed low power consumption and 98-99% salt removal, however, the EDI system required 25-30% less power for silica removal. For Phase 2, the EDI system's performance was optimized and the length of time between clean-in-place (CIP) increased by varying the wafer composition and membrane configuration. The enhanced EDI system could remove 88% of the hardness and 99% of the alkalinity with a processing flux of 19.2 gal/hr/m{sup 2} and a power consumption of 0.54 kWh/100 gal water. Bench tests to screen alternative silica/silicate scale inhibitor chemistries have begun. The silica/silicate control approaches using chemical inhibitors include inhibition of silicic acid polymerization and dispersion of silica/silicate crystals. Tests were conducted with an initial silica concentration of 290-300 mg/L as SiO{sub 2} at pH 7 and room temperature. A proprietary new chemistry was found to be promising, compared with a current commercial product commonly used for silica/silicate control. Additional pilot cooling tower testing confirmed the bench study. We also developed a molecule to inhibit calcium carbonate precipitation and calcium sulfate precipitation at high supersaturations. During Phase 3, a long-term test of the EDI system and scale inhibitors was done at Nalco's cooling tower water testing facility, producing 850 gallons of high purity water (90+% salt removal) at a rate of 220 L/day. The EDI system's performance was stable when the salt concentration in the concentrate compartment (i.e. the EDI waste stream) was controlled and a CIP was done after every 48 hours of operation time. A combination of EDI and scale inhibitors completely eliminated blowdown discharge from the Pilot cooling Tower. The only water-consumption came from evaporation, CIP and EDI concentrate. Silica Inhibitor was evaluated in the field at a western coal fired power plant.« less

Cooling characteristics of air cooled radial turbine blades

NASA Astrophysics Data System (ADS)

Sato, T.; Takeishi, K.; Matsuura, M.; Miyauchi, J.

The cooling design and the cooling characteristics of air cooled radial turbine wheels, which are designed for use with the gas generator turbine for the 400 horse power truck gas turbine engine, are presented. A high temperature and high speed test was performed under aerodynamically similar conditions to that of the prototype engine in order to confirm the metal temperature of the newly developed integrated casting wheels constructed of the superalloys INCO 713C. The test results compared with the analytical value, which was established on the basis of the results of the heat transfer test and the water flow test, are discussed.

Passive cooling system for top entry liquid metal cooled nuclear reactors

DOEpatents

Boardman, Charles E.; Hunsbedt, Anstein; Hui, Marvin M.

1992-01-01

A liquid metal cooled nuclear fission reactor plant having a top entry loop joined satellite assembly with a passive auxiliary safety cooling system for removing residual heat resulting from fuel decay during shutdown, or heat produced during a mishap. This satellite type reactor plant is enhanced by a backup or secondary passive safety cooling system which augments the primary passive auxiliary cooling system when in operation, and replaces the primary cooling system when rendered inoperative.

Summary of space nuclear reactor power systems, 1983--1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buden, D.

1993-08-11

This report summarizes major developments in the last ten years which have greatly expanded the space nuclear reactor power systems technology base. In the SP-100 program, after a competition between liquid-metal, gas-cooled, thermionic, and heat pipe reactors integrated with various combinations of thermoelectric thermionic, Brayton, Rankine, and Stirling energy conversion systems, three concepts:were selected for further evaluation. In 1985, the high-temperature (1,350 K), lithium-cooled reactor with thermoelectric conversion was selected for full scale development. Since then, significant progress has been achieved including the demonstration of a 7-y-life uranium nitride fuel pin. Progress on the lithium-cooled reactor with thermoelectrics has progressedmore » from a concept, through a generic flight system design, to the design, development, and testing of specific components. Meanwhile, the USSR in 1987--88 orbited a new generation of nuclear power systems beyond the, thermoelectric plants on the RORSAT satellites. The US has continued to advance its own thermionic fuel element development, concentrating on a multicell fuel element configuration. Experimental work has demonstrated a single cell operating time of about 1 1/2-y. Technology advances have also been made in the Stirling engine; an advanced engine that operates at 1,050 K is ready for testing. Additional concepts have been studied and experiments have been performed on a variety of systems to meet changing needs; such as powers of tens-to-hundreds of megawatts and highly survivable systems of tens-of-kilowatts power.« less

Summary of space nuclear reactor power systems, 1983 - 1992

NASA Astrophysics Data System (ADS)

Buden, D.

1993-08-01

This report summarizes major developments in the last ten years which have greatly expanded the space nuclear reactor power systems technology base. In the SP-100 program, after a competition between liquid-metal, gas-cooled, thermionic, and heat pipe reactors integrated with various combinations of thermoelectric thermionic, Brayton, Rankine, and Stirling energy conversion systems, three concepts were selected for further evaluation. In 1985, the high-temperature (1,350 K), lithium-cooled reactor with thermoelectric conversion was selected for full scale development. Since then, significant progress has been achieved including the demonstration of a 7-y-life uranium nitride fuel pin. Progress on the lithium-cooled reactor with thermoelectrics has progressed from a concept, through a generic flight system design, to the design, development, and testing of specific components. Meanwhile, the USSR in 1987-88 orbited a new generation of nuclear power systems beyond the, thermoelectric plants on the RORSAT satellites. The US has continued to advance its own thermionic fuel element development, concentrating on a multicell fuel element configuration. Experimental work has demonstrated a single cell operating time of about 1 1/2-y. Technology advances have also been made in the Stirling engine; an advanced engine that operates at 1,050 K is ready for testing. Additional concepts have been studied and experiments have been performed on a variety of systems to meet changing needs; such as powers of tens-to-hundreds of megawatts and highly survivable systems of tens-of-kilowatts power.

Research: Testing of a Novel Portable Body Temperature Conditioner Using a Thermal Manikin.

PubMed

Heller, Daniel; Heller, Alex; Moujaes, Samir; Williams, Shelley J; Hoffmann, Ryan; Sarkisian, Paul; Khalili, Kaveh; Rockenfeller, Uwe; Browder, Timothy D; Kuhls, Deborah A; Fildes, John J

2016-01-01

A battery-operated active cooling/heating device was developed to maintain thermoregulation of trauma victims in austere environments while awaiting evacuation to a hospital for further treatment. The use of a thermal manikin was adopted for this study in order to simulate load testing and evaluate the performance of this novel portable active cooling/heating device for both continuous (external power source) and battery power. The performance of the portable body temperature conditioner (PBTC) was evaluated through cooling/heating fraction tests to analyze the heat transfer between a thermal manikin and circulating water blanket to show consistent performance while operating under battery power. For the cooling/heating fraction tests, the ambient temperature was set to 15°C ± 1°C (heating) and 30°C ± 1°C (cooling). The PBTC water temperature was set to 37°C for the heating mode tests and 15°C for the cooling mode tests. The results showed consistent performance of the PBTC in terms of cooling/heating capacity while operating under both continuous and battery power. The PBTC functioned as intended and shows promise as a portable warming/cooling device for operation in the field.

Aberration compensation in a Skew parametric-resonance ionization cooling channel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sy, Amy V.; Derbenev, Yaroslav S.; Morozov, Vasiliy

Skew Parametric-resonance Ionization Cooling (Skew PIC) represents a novel method for focusing of highly divergent particle beams, as in the final 6D cooling stage of a high-luminosity muon collider. In the muon collider concept, the resultant equilibrium transverse emittances from cooling with Skew PIC are an order of magnitude smaller than in conventional ionization cooling. The concept makes use of coupling of the transverse dynamic behavior, and the linear dynamics are well-behaved with good agreement between analytic solutions and simulation results. Compared to the uncoupled system, coupling of the transverse dynamic behavior purports to reduce the number of multipoles requiredmore » for aberration compensation while also avoiding unwanted resonances. Aberration compensation is more complicated in the coupled case, especially in the high-luminosity muon collider application where equilibrium angular spreads in the cooling channel are on the order of 200 mrad. We present recent progress on aberration compensation for control of highly divergent muon beams in the coupled correlated optics channel, and a simple cooling model to test the transverse acceptance of the channel.« less

Transient Three-Dimensional Startup Side Load Analysis of a Regeneratively Cooled Nozzle

NASA Technical Reports Server (NTRS)

Wang, Ten-See

2008-01-01

The objective of this effort is to develop a computational methodology to capture the startup side load physics and to anchor the computed aerodynamic side loads with the available data from a regeneratively cooled, high-aspect-ratio nozzle, hot-fired at sea level. The computational methodology is based on an unstructured-grid, pressure-based, reacting flow computational fluid dynamics and heat transfer formulation, a transient 5 s inlet history based on an engine system simulation, and a wall temperature distribution to reflect the effect of regenerative cooling. To understand the effect of regenerative wall cooling, two transient computations were performed using the boundary conditions of adiabatic and cooled walls, respectively. The results show that three types of shock evolution are responsible for side loads: generation of combustion wave; transitions among free-shock separation, restricted-shock separation, and simultaneous free-shock and restricted shock separations; along with the pulsation of shocks across the lip, although the combustion wave is commonly eliminated with the sparklers during actual test. The test measured two side load events: a secondary and lower side load, followed by a primary and peak side load. Results from both wall boundary conditions captured the free-shock separation to restricted-shock separation transition with computed side loads matching the measured secondary side load. For the primary side load, the cooled wall transient produced restricted-shock pulsation across the nozzle lip with peak side load matching that of the test, while the adiabatic wall transient captured shock transitions and free-shock pulsation across the lip with computed peak side load 50% lower than that of the measurement. The computed dominant pulsation frequency of the cooled wall nozzle agrees with that of a separate test, while that of the adiabatic wall nozzle is more than 50% lower than that of the measurement. The computed teepee-like formation and the tangential motion of the shocks during lip pulsation also qualitatively agree with those of test observations. Moreover, a third transient computation was performed with a proportionately shortened 1 s sequence, and lower side loads were obtained with the higher ramp rate.

A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

NASA Astrophysics Data System (ADS)

Navarro, Jorge

The goal of this study presented is to determine the best available nondestructive technique necessary to collect validation data as well as to determine burnup and cooling time of the fuel elements on-site at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal, the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements nondestructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed were used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results, it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however, in order to enhance the quality of the spectra collected using this scintillator, a deconvolution method was developed. Following the development of the deconvolution method for ATR applications, the technique was tested using one-isotope, multi-isotope, and fuel simulated sources. Burnup calibrations were perfomed using convoluted and deconvoluted data. The calibrations results showed burnup prediction by this method improves using deconvolution. The final stage of the deconvolution method development was to perform an irradiation experiment in order to create a surrogate fuel source to test the deconvolution method using experimental data. A conceptual design of the fuel scan system is path forward using the rugged LaBr 3 detector in an above the water configuration and deconvolution algorithms.

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2011 CFR

2011-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2010 CFR

2010-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2013 CFR

2013-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2012 CFR

2012-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2014 CFR

2014-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...