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1

Heat Pipe Integrated Microsystems  

SciTech Connect

The trend in commercial electronics packaging to deliver ever smaller component packaging has enabled the development of new highly integrated modules meeting the demands of the next generation nano satellites. At under ten kilograms, these nano satellites will require both a greater density electronics and a melding of satellite structure and function. Better techniques must be developed to remove the subsequent heat generated by the active components required to-meet future computing requirements. Integration of commercially available electronics must be achieved without the increased costs normally associated with current generation multi chip modules. In this paper we present a method of component integration that uses silicon heat pipe technology and advanced flexible laminate circuit board technology to achieve thermal control and satellite structure. The' electronics/heat pipe stack then becomes an integral component of the spacecraft structure. Thermal management on satellites has always been a problem. The shrinking size of electronics and voltage requirements and the accompanying reduction in power dissipation has helped the situation somewhat. Nevertheless, the demands for increased onboard processing power have resulted in an ever increasing power density within the satellite body. With the introduction of nano satellites, small satellites under ten kilograms and under 1000 cubic inches, the area available on which to place hot components for proper heat dissipation has dwindled dramatically. The resulting satellite has become nearly a solid mass of electronics with nowhere to dissipate heat to space. The silicon heat pipe is attached to an aluminum frame using a thermally conductive epoxy or solder preform. The frame serves three purposes. First, the aluminum frame provides a heat conduction path from the edge of the heat pipe to radiators on the surface of the satellite. Secondly, it serves as an attachment point for extended structures attached to the satellite such as solar panels, radiators, antenna and.telescopes (for communications or sensors). Finally, the packages make thermal contact to the surface of the silicon heat pipe through soft thermal pads. Electronic components can be placed on both sides of the flexible circuit interconnect. Silicon heat pipes have a number of advantages over heat pipe constructed from other materials. Silicon heat pipes offer the ability to put the heat pipe structure beneath the active components of a processed silicon wafer. This would be one way of efficiently cooling the heat generated by wafer scale integrated systems. Using this technique, all the functions of a satellite could be reduced to a few silicon wafers. The integration of the heat pipe and the electronics would further reduce the size and weight of the satellite.

Gass, K.; Robertson, P.J.; Shul, R.; Tigges, C.

1999-03-30

2

Integrating preconcentrator heat controller  

DOEpatents

A method and apparatus for controlling the electric resistance heating of a metallic chemical preconcentrator screen, for example, used in portable trace explosives detectors. The length of the heating time-period is automatically adjusted to compensate for any changes in the voltage driving the heating current across the screen, for example, due to gradual discharge or aging of a battery. The total deposited energy in the screen is proportional to the integral over time of the square of the voltage drop across the screen. Since the net temperature rise, .DELTA.T.sub.s, of the screen, from beginning to end of the heating pulse, is proportional to the total amount of heat energy deposited in the screen during the heating pulse, then this integral can be calculated in real-time and used to terminate the heating current when a pre-set target value has been reached; thereby providing a consistent and reliable screen temperature rise, .DELTA.T.sub.s, from pulse-to-pulse.

Bouchier, Francis A. (Albuquerque, NM); Arakaki, Lester H. (Edgewood, NM); Varley, Eric S. (Albuquerque, NM)

2007-10-16

3

Heat Pipe Integrated Microsystems.  

National Technical Information Service (NTIS)

The trend in commercial electronics packaging to deliver ever smaller component packaging has enabled the development of new highly integrated modules meeting the demands of the next generation nano satellites. At under ten kilograms, these nano satellite...

K. Gass P. J. Robertson R. Shul C. Tigges

1999-01-01

4

Heat Pipe Integrated Microsystems  

Microsoft Academic Search

The trend in commercial electronics packaging to deliver ever smaller component packaging has enabled the development of new highly integrated modules meeting the demands of the next generation nano satellites. At under ten kilograms, these nano satellites will require both a greater density electronics and a melding of satellite structure and function. Better techniques must be developed to remove the

K. Gass; P. J. Robertson; R. Shul; C. Tigges

1999-01-01

5

Integrated Heat Switch/Oxide Sorption Compressor  

NASA Technical Reports Server (NTRS)

Thermally-driven, nonmechanical compressor uses container filled with compressed praseodymium cerium oxide powder (PrCeOx) to provide high-pressure flow of oxygen gas for driving closed-cycle Joule-Thomson-expansion refrigeration unit. Integrated heat switch/oxide sorption compressor has no moving parts except check valves, which control flow of oxygen gas between compressor and closed-cycle Joule-Thomson refrigeration system. Oxygen expelled from sorbent at high pressure by evacuating heat-switch gap and turning on heater.

Bard, Steven

1989-01-01

6

Integral solar and heat pump water heating system  

SciTech Connect

A multi-mode water heating system wherein a capacity control mechanism is provide so that no additional heat source is required and via use of capacity control, either solar radiation energy or ambient air energy is selectively utilized dependent on the availability of sunshine. A system configuration is so arranged as to maximize the system seasonal coefficient of performance by a refrigeration cycle optimization which adjusts both a pump/compressor speed and pressure regulating valve opening.

Yoshino, H.

1985-04-02

7

Performance of Integrated Hydronic Heating Systems.  

SciTech Connect

A variety of system configurations are used in North America to meet the heating and domestic hot water needs of single-family homes. This includes, for example: warm air furnaces with electric water heaters; boilers with integrated hot water coils; and boilers with 'indirect' hot water storage tanks. Integrated hydronic systems which provide both heat and hot water are more popular only in the Northeast and mid-Atlantic regions. For those making decisions about configurations of these integrated hydronic systems, including control options, little information is available concerning the annual energy cost implications of these decisions. This report presents results of a project to use a direct load emulation approach to measure the performance of hydronic systems, develop performance curves, and to provide decision tools to consumers. This is a laboratory measurement system involving direct energy input and output measurements under different load patterns. These results are then used to develop performance correlations for specific systems that can be used to predict energy use in specific applications. A wide range of system types have been tested under this project including conventional boilers with 'tankless' internal coils for domestic hot water production, boilers with indirect external storage tanks, tank type water heaters which may also be used for space heating, condensing oil- and gas-fired systems, and systems with custom control features. It is shown that low load and idle energy losses can have a very large impact on the total annual energy use and that the potential energy savings associated with replacing old equipment with newer, high efficiency equipment with low losses at idle or low load can be in the 25% range. These savings are larger than simple combustion efficiency measurements would indicate.

BUTCHER,T.A.

2007-12-20

8

Multifunctional composites: Healing, heating and electromagnetic integration  

NASA Astrophysics Data System (ADS)

Multifunctional materials, in the context of this research, integrate other functions into materials that foremost have outstanding structural integrity. Details of the integration of electromagnetic, heating, and healing functionalities into fiber-reinforced polymer composites are presented. As a result of fiber/wire integration through textile braiding and weaving, the dielectric constant of a composite may be tuned from negative to positive values. These wires are further leveraged to uniformly heat the composite through resistive heating. A healing functionality is introduced by utilizing a polymer matrix with the ability to heal internal cracking through thermally-reversible covalent bonds based on Diels-Alder cycloaddition. The Double Cleavage Drilled Compression (DCDC) specimen is applied to study the fracture and healing characteristics of the neat polymer. This method allows for quantitative evaluation of incremental crack growth, and ensures that the cracked sample remains in one piece after the test, improving the ability to re-align the fracture surfaces prior to healing. Initially, the fracture strength of PMMA is studied with various DCDC geometries to develop a model of the propagation of a crack within this type of specimen. Applied to the healable polymer (2MEP4F), repeated fracture-healing cycles demonstrate that treatment at temperatures between 85 to 95°C results in full fracture toughness recovery and no dimensional changes due to creep. The fracture toughness after each fracturing and healing cycle has been calculated, using the model, to yield a fracture toughness of about 0.71 MPa·m1/2 for this material at room temperature. Glass and carbon fiber-reinforced composites have been fabricated with the 2MEP4F polymer, and the ability of this polymer to heal microcracks in fiber-reinforced composites is demonstrated. Microcracks have been introduced into the composites by cryogenic cycling in liquid nitrogen, causing a reduction in the storage modulus of the composites as measured by Dynamic Mechanical Thermal Analysis (DMTA). Heating the laminate with pressure applied normal to transverse microcracks appeared to repair the cracks and partially recover of the composite's stiffness. Multifunctional composites with such unique capabilities have tremendous potential to impact future structural applications.

Plaisted, Thomas Anthony John

9

Integrated cooling, heating, and power systems  

US Patent & Trademark Office Database

One exemplary embodiment of this invention provides a single-effect absorption chiller including an absorber operatively connected to a solution heat exchanger and a generator, and a condenser in fluid communication with the absorber, wherein the absorber is sized and configured to receive a feed of water from a source of water and to transfer heat to the feed of water and then to convey the feed of water to the condenser without further heat conditioning of the feed of water prior to its entry into the condenser, and wherein the condenser is sized and configured to receive the feed of water from the absorber and to transfer heat to the feed of water, thereby cooling the condenser without resorting to an external heat exchanger such as a conventional cooling tower.

2014-06-03

10

Internally Heat-Integrated Distillation Columns: A Review  

Microsoft Academic Search

The heat-integrated distillation column to be addressed in this paper is a special distillation column that involves internal heat integration between the whole rectifying and the whole stripping sections. An overview of the research on this process is presented in this work. It covers from the thermodynamic development and evaluations to the practical design and operation investigations for the process.

M. Nakaiwa; K. Huang; A. Endo; T. Ohmori; T. Akiya; T. Takamatsu

2003-01-01

11

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters  

SciTech Connect

This report discusses how a significant opportunity for energy savings is domestic hot water heating, where an emerging technology has recently arrived in the U.S. market: the residential integrated heat pump water heater. A laboratory evaluation is presented of the five integrated HPWHs available in the U.S. today.

Sparn, B.; Hudon, K.; Christensen, D.

2011-09-01

12

Integrated kinetics and heat flow modelling to optimise waste tyre pyrolysis at different heating rates  

Microsoft Academic Search

Pyrolysis is a promising technology to tackle the waste tyre disposal problem via converting the waste tyres into hydrocarbon fuels. This paper uses the experimental data of tyre pyrolysis (TGA\\/DTG and DTA) to examine both the kinetics and the heat flow at various heating rates for large tyre particles. An integrated model that considers the mass loss kinetics, exothermic kinetics,

Kwok-Yuen Cheung; King-Lung Lee; Ka-Leung Lam; Chi-Wui Lee; Chi-Wai Hui

2011-01-01

13

Application of process integration to utilities, combined heat and power, and heat pumps  

NASA Astrophysics Data System (ADS)

This Data Item 89001, an addition to the Heat Transfer Subseries, shows how the techniques of process integration introduced in ESDU 87030, where they were used to optimize heat exchanger networks, can be extended to design optimally the heat and power systems of a process plant or site. After briefly describing the thermodynamic principles of heating and cooling systems, the various types of heat engines and heat pumps that may be used are introduced, and criteria for their selection to achieve an optimal combined heat and power system are explained. Heat engines include steam and gas turbines and diesel engines, while heat pumps cover mechanical and thermal vapor recompression, refrigeration cycles, and heat transformers. The optimization process covers not only the selection of an appropriate type of utility of the correct size, but also its placement within the process. The application of the techniques is illustrated using the real case study also used in ESDU 87030, and further case studies using current economic and numerical data extend the user's appreciation of the methods.

1989-04-01

14

Efficient adsorption refrigerators integrated with heat pipes  

Microsoft Academic Search

Several novel ideas to use heat pipes in adsorption water chiller or ice maker are presented in this paper. Experimental results have shown that the adsorption refrigerators are very efficient. The first example of such systems is a small scale silica gel–water adsorption water chiller with cooling power rated as 10kW; the system could be powered by 60–100°C hot water,

R. Z. Wang

2008-01-01

15

Integrated heat pipe-thermal storage system performance evaluation  

SciTech Connect

Performance verification tests of an integrated heat pipe-thermal energy storage system have been conducted. This system is being developed as a part of an Organic Rankine Cycle-Solar Dynamic Power System (ORC-SDPS) receiver for future space stations. The integrated system consists of potassium heat pipe elements that incorporate thermal energy storage (TES) canisters within the vapor space along with an organic fluid (toluene) heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the surface of the heat pipe elements of the ORC-SDPS receiver and is internally transferred by the potassium vapor for use and storage. Part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the stored energy in the TES units is transferred by the potassium vapor to the toluene heater tube. A developmental heat pipe element was fabricated that employs axial arteries and a distribution wick connecting the wicked TES units and the heater to the solar insolation surface of the heat pipe. Tests were conducted to verify the heat pipe operation and to evaluate the heat pipe/TES units/heater tube operation by interfacing the heater unit to a heat exchanger.

Keddy, E.; Sena, J.T.; Merrigan, M.

1987-01-01

16

A solar air collector with integrated latent heat thermal storage  

NASA Astrophysics Data System (ADS)

Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data).

Charvat, Pavel; Ostry, Milan; Mauder, Tomas; Klimes, Lubomir

2012-04-01

17

Integral-type solar-assisted heat pump water heater  

Microsoft Academic Search

An integral-type solar-assisted heat pump water heater (ISAHP) is designed and tested in the present study. The storage tank and the Rankine cycle unit are integrated together to make a more compact size. A thermosyphon loop is used to transfer the heat from the condenser to the water storage tank. The highest COP obtained in the tests is 3.83.

B. J. Huang; J. P. Chyng

1999-01-01

18

Development of an Air-Source Heat Pump Integrated with a Water Heating / Dehumidification Module  

SciTech Connect

A residential-sized dual air-source integrated heat pump (AS-IHP) concept is under development in partnership between ORNL and a manufacturer. The concept design consists of a two-stage air-source heat pump (ASHP) coupled on the air distribution side with a separate novel water heating/dehumidification (WH/DH) module. The motivation for this unusual equipment combination is the forecast trend for home sensible loads to be reduced more than latent loads. Integration of water heating with a space dehumidification cycle addresses humidity control while performing double-duty. This approach can be applied to retrofit/upgrade applications as well as new construction. A WH/DH module capable of ~1.47 L/h water removal and ~2 kW water heating capacity was assembled by the manufacturer. A heat pump system model was used to guide the controls design; lab testing was conducted and used to calibrate the models. Performance maps were generated and used in a TRNSYS sub-hourly simulation to predict annual performance in a well-insulated house. Annual HVAC/WH energy savings of ~35% are predicted in cold and hot-humid U.S. climates compared to a minimum efficiency baseline.

Rice, C Keith [ORNL] [ORNL; Uselton, Robert B. [Lennox Industries, Inc] [Lennox Industries, Inc; Shen, Bo [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Shrestha, Som S [ORNL] [ORNL

2014-01-01

19

Air, contaminant and heat transport models: integration and application  

Microsoft Academic Search

Comfort evaluations cover air quality, thermal, visual and acoustic comfort. Today, only few computer programs allow for the integrated evaluation of several or all relevant parameters. Heat transport, ventilation as well as lighting in a room are influenced by each other. Therefore they should be integrally modelled. As a part of the IEA-ECBCS Annex 23 `Multizone Airflow Modelling', such a

V Dorer; A Weber

1999-01-01

20

Heat integration and analysis of decarbonised IGCC sites  

Microsoft Academic Search

Integrated gasification combined cycle (IGCC) power generation systems have become of interest due to their high combined heat and power (CHP) generation efficiency and flexibility to include carbon capture and storage (CCS) in order to reduce CO2 emissions. However, IGCC's biggest challenge is its high cost of energy production. In this study, decarbonised coal IGCC sites integrated with CCS have

Kok Siew Ng; Yadira Lopez; Grant M. Campbell; Jhuma Sadhukhan

2010-01-01

21

Modular Micromachined Si Heat Removal (MOMS Heat Removal): Electronic Integration and System Test.  

National Technical Information Service (NTIS)

The UCLA group headed by Dr. Elliott Brown and the Rockwell Scientific group headed by Dr. Michael Shaw conducted extensive research for the DARPA HERETIC Program on the integration of two heat-removal approaches with power electronic devices, (1) micro h...

E. R. Brown

2003-01-01

22

Integrated heat pipe-thermal storage system performance evaluation  

NASA Astrophysics Data System (ADS)

An integrated thermal energy storage (TES) system, developed as a part of an organic Rankine cycle solar dynamic power system is described, and the results of the performance verification tests of this TES system are presented. The integrated system consists of potassium heat-pipe elements that incorporate TES canisters within the vapor space, along with an organic fluid heater tube used as the condenser region of the heat pipe. The heat pipe assembly was operated through the range of design conditions from the nominal design input of 4.8 kW to a maximum of 5.7 kW. The performance verification tests show that the system meets the functional requirements of absorbing the solar energy reflected by the concentrator, transporting the energy to the organic Rankine heater, providing thermal storage for the eclipse phase, and allowing uniform discharge from the thermal storage to the heater.

Keddy, E.; Sena, J. T.; Merrigan, M.; Heidenreich, Gary

23

Integrated heat pipe-thermal storage system performance evaluation  

NASA Technical Reports Server (NTRS)

An integrated thermal energy storage (TES) system, developed as a part of an organic Rankine cycle solar dynamic power system is described, and the results of the performance verification tests of this TES system are presented. The integrated system consists of potassium heat-pipe elements that incorporate TES canisters within the vapor space, along with an organic fluid heater tube used as the condenser region of the heat pipe. The heat pipe assembly was operated through the range of design conditions from the nominal design input of 4.8 kW to a maximum of 5.7 kW. The performance verification tests show that the system meets the functional requirements of absorbing the solar energy reflected by the concentrator, transporting the energy to the organic Rankine heater, providing thermal storage for the eclipse phase, and allowing uniform discharge from the thermal storage to the heater.

Keddy, E.; Sena, J. T.; Merrigan, M.; Heidenreich, Gary

1987-01-01

24

EVALUATING HEAT INTEGRATION SCHEME FOR BATCH PRODUCTION OF OLEIC ACID  

Microsoft Academic Search

Research works on Process System Engineering are well established for conventional sectors of bulk chemical manufacturing, such as that in the oil and gas and petrochemical industries. However, relatively less attention has been given to the area of bio-related and fine chemical production. This paper demonstrates the use of process synthesis and analysis tools in evaluating heat integration schemes for

Chew Yin Hoon; Lee Chew Tin; Dominic Foo; Chwan Yee

25

Integration of light delivery for heat assisted magnetic recording  

Microsoft Academic Search

Light delivery with spot size converter (SSC) and optical fiber for heat assisted magnetic recording is proposed. It has an advantage in optical efficiency and integration tolerance. SSC was fabricated and confirmed its operation. Fly-ability of pico slider with optical fiber was also demonstrated.

M. Hirata; M. Oumi; S. Tanabe; N. Chiba; L. Gonzaga; S. Yu; M. Zhang; F. Tjiptoharsono

2009-01-01

26

Integrated heating and ventilation: Double duty for ducts  

Microsoft Academic Search

Under the right conditions, integrated systems work well and have a fairly minimal energy penalty. However, the right conditions are not common in Northwest housing stock. Houses typically are built with heating system supply ducts located in crawl spaces and return plenums in attics. duct leakage is usually large, in excess of 100 cfm, as is the potential for conductive

2009-01-01

27

Test results of a Stirling engine utilizing heat exchanger modules with an integral heat pipe  

NASA Technical Reports Server (NTRS)

The Heat Pipe Stirling Engine (HP-1000), a free-piston Stirling engine incorporating three heat exchanger modules, each having a sodium filled heat pipe, has been tested at the NASA-Lewis Research Center as part of the Civil Space Technology Initiative (CSTI). The heat exchanger modules were designed to reduce the number of potential flow leak paths in the heat exchanger assembly and incorporate a heat pipe as the link between the heat source and the engine. An existing RE-1000 free-piston Stirling engine was modified to operate using the heat exchanger modules. This paper describes heat exchanger module and engine performance during baseline testing. Condenser temperature profiles, brake power, and efficiency are presented and discussed.

Skupinski, Robert C.; Tower, Leonard K.; Madi, Frank J.; Brusk, Kevin D.

1993-01-01

28

Development of a modular heat exchanger with integrated latent heat energy store  

NASA Astrophysics Data System (ADS)

Latent heat storage materials and appropriate heat exchangers for solar heating applications, such as house heating and domestic hot water production were investigated. The melting and freezing characteristics and the effects of thermal cycling on a total of 12 substances, including paraffins, fatty acids and salt hydrates, were investigated and their corrosive interaction with five conventional construction materials was determined. The poor thermal conductivity of the heat storage materials requires the development of a modular finned heat pipe heat exchanger with increased heat transfer characteristics. A cost analysis is provided and comparisons with hot water storage indicate that latent heat storage has the potential of becoming economically more attractive than the former for domestic hot water production.

Abhat, A.; Heine, D.; Heinisch, M.; Malatidis, N. A.; Neuer, G.

1981-02-01

29

Analysis of integrated heat pumps by the 'null engine' concept  

NASA Astrophysics Data System (ADS)

Results are presented of a theoretical analysis of a generalized configuration where energy input is in the form of thermal energy only and the system can be used either as a heat pump or a refrigerator. A new concept of a 'null engine' is introduced in order to establish quantitative relationships between engine proportions and operating characteristics. The generalized heat-operated Vuilleumier machine is analyzed from first principles based on the applicable temperature-entropy diagrams. From this, a theoretical volume ratio between the cold and the hot expansion space in a Vuilleumier machine is deduced. A theoretical minimum for operational hardware which will ensure an energy balance for an ideal integrated heat pump is established.

Finkelstein, Theodor

30

Integration of Heat-Pulse and Sensible Heat Balance Methods to Estimate Evaporation From Bare Soils  

NASA Astrophysics Data System (ADS)

A critical component of the water cycle at local, regional and global scales is evaporation from soil. Because it is very difficult to measure soil evaporation and soil moisture in the field, with the exception of using a lysimeter for local measurements, numerous model based estimation methods have been proposed. Numerical approaches that attempt to estimate evaporation rates within the top several centimeters of soil often rely of empirical and semi-empirical methods. Another less well known method to determine evaporation relies on heat pulse sensors to measure soil temperature and thermal properties. This approach does not rely on knowledge of soil hydraulic properties, effectively removing the need of several common empirical methods to define the soil surface boundary condition. The objective of this study was to integrate both the heat-pulse and sensible heat balance methods into a non-isothermal multiphase flow model in order to define the boundary conditions at the land/atmosphere interface. This model was tested using precision experimental data collected under laboratory conditions and compared to more traditional numerical modeling approaches. Experimental data was generated in a two-dimensional soil tank containing an array of sensors that allowed soil temperature, soil moisture content, and relative humidity to be collected continuously and autonomously. The soil tank was placed within a wind tunnel test facility to insure that atmospheric conditions were carefully controlled and monitored throughout the duration of the experiment. Numerical results of the model using the heat pulse and sensible heat balance methods were compared to those generated using different, more traditional modeling approaches. Results demonstrate the applicability of incorporating the heat-pulse and sensible heat balance methods in numerical approaches. Further validation was provided through a comparison of the numerical results and independently determined experimental results. This numerical approach shows great ability to accurately predict soil-water evaporation rates at fine spatial and temporal scales. Results of this study will be used in future research for larger, more complex atmospheric conditions and soil heterogeneities.

Trautz, A.; Smits, K. M.; Schulte, P.; Cihan, A.; Illangasekare, T. H.

2012-12-01

31

The design and fabrication of a Stirling engine heat exchanger module with an integral heat pipe  

NASA Astrophysics Data System (ADS)

The conceptual design of a free-piston Stirling Space Engine (SSE) intended for space power applications has been generated. The engine was designed to produce 25 kW of electric power with heat supplied by a nuclear reactor. A novel heat exchanger module was designed to reduce the number of critical joints in the heat exchanger assembly while also incorporating a heat pipe as the link between the engine and the heat source. Two inexpensive verification tests are proposed. The SSE heat exchanger module is described and the operating conditions for the module are outlined. The design process of the heat exchanger modules, including the sodium heat pipe, is briefly described. Similarities between the proposed SSE heat exchanger modules and the LeRC test modules for two test engines are presented. The benefits and weaknesses of using a sodium heat pipe to transport heat to a Stirling engine are discussed. Similarly, the problems encountered when using a true heat pipe, as opposed to a more simple reflux boiler, are described. The instruments incorporated into the modules and the test program are also outlined.

Schreiber, Jeffrey G.

32

The design and fabrication of a Stirling engine heat exchanger module with an integral heat pipe  

NASA Astrophysics Data System (ADS)

The conceptual design of a free-piston Stirling Space Engine (SSE) intended for space power applications has been generated. The engine was designed to produce 25 kW of electric power with heat supplied by a nuclear reactor. A novel heat exchanger module was designed to reduce the number of critical joints in the heat exchanger assembly while also incorporating a heat pipe as the link between the engine and the heat source. Two inexpensive verification tests are proposed. The SSE heat exchanger module is described and the operating conditions for the module are outlined. The design process of the heat exchanger modules, including the sodium heat pipe, is briefly described. Similarities between the proposed SSE heat exchanger modules and the LeRC test modules for two test engines are presented. The benefits and weaknesses of using a sodium heat pipe to transport heat to a Stirling engine are discussed. Similarly, the problems encountered when using a true heat pipe, as opposed to a more simple reflux boiler, are described. The instruments incorporated into the modules and the test program are also outlined.

Schreiber, Jeffrey G.

1988-05-01

33

The design and fabrication of a Stirling engine heat exchanger module with an integral heat pipe  

NASA Technical Reports Server (NTRS)

The conceptual design of a free-piston Stirling Space Engine (SSE) intended for space power applications has been generated. The engine was designed to produce 25 kW of electric power with heat supplied by a nuclear reactor. A novel heat exchanger module was designed to reduce the number of critical joints in the heat exchanger assembly while also incorporating a heat pipe as the link between the engine and the heat source. Two inexpensive verification tests are proposed. The SSE heat exchanger module is described and the operating conditions for the module are outlined. The design process of the heat exchanger modules, including the sodium heat pipe, is briefly described. Similarities between the proposed SSE heat exchanger modules and the LeRC test modules for two test engines are presented. The benefits and weaknesses of using a sodium heat pipe to transport heat to a Stirling engine are discussed. Similarly, the problems encountered when using a true heat pipe, as opposed to a more simple reflux boiler, are described. The instruments incorporated into the modules and the test program are also outlined.

Schreiber, Jeffrey G.

1988-01-01

34

Heating with waste heat  

SciTech Connect

Most of the power consumed in the gaseous diffusion process is converted into heat of compression, which is removed from the process gas and rejected into the atmosphere by recirculating cooling water over cooling towers. The water being handled through the X-333 and X-330 Process Buildings can be heated to 140 to 150/sup 0/F for heating use. The Gas Centrifuge Enrichment Plant is provided with a recirculating heating water (RHW) system which uses X-330 water and wasted heat. The RHW flow is diagrammed. (DLC)

Beabout, R.W.

1986-09-02

35

Integration of Heat Transfer, Stress, and Particle Trajectory Simulation  

SciTech Connect

Calabazas Creek Research, Inc. developed and currently markets Beam Optics Analyzer (BOA) in the United States and abroad. BOA is a 3D, charged particle optics code that solves the electric and magnetic fields with and without the presence of particles. It includes automatic and adaptive meshing to resolve spatial scales ranging from a few millimeters to meters. It is fully integrated with CAD packages, such as SolidWorks, allowing seamless geometry updates. The code includes iterative procedures for optimization, including a fully functional, graphical user interface. Recently, time dependent, particle in cell capability was added, pushing particles synchronically under quasistatic electromagnetic fields to obtain particle bunching under RF conditions. A heat transfer solver was added during this Phase I program. Completed tasks include: (1) Added a 3D finite element heat transfer solver with adaptivity; (2) Determined the accuracy of the linear heat transfer field solver to provide the basis for development of higher order solvers in Phase II; (3) Provided more accurate and smoother power density fields; and (4) Defined the geometry using the same CAD model, while maintaining different meshes, and interfacing the power density field between the particle simulator and heat transfer solvers. These objectives were achieved using modern programming techniques and algorithms. All programming was in C++ and parallelization in OpenMP, utilizing state-of-the-art multi-core technology. Both x86 and x64 versions are supported. The GUI design and implementation used Microsoft Foundation Class.

Thuc Bui; Michael Read; Lawrence ives

2012-05-17

36

Conjugate heat transfer in fractal-shaped microchannel network heat sink for integrated microelectronic cooling application  

Microsoft Academic Search

The hydrodynamic and thermal characteristics of fractal-shaped microchannel network heat sinks are investigated numerically by solving three-dimensional N–S equations and energy equation, taking into consideration the conjugate heat transfer in microchannel walls. It is found that due to the structural limitation of right-angled fractal-shaped microchannel network, hotspots may appear on the bottom wall of the heat sink where the microchannels

F. J. Hong; P. Cheng; H. Ge; Goh Teck Joo

2007-01-01

37

Heat-Transfer Coupling For Heat Pipes  

NASA Technical Reports Server (NTRS)

Proposed welded heat-transfer coupling joins set of heat pipes to thermoelectric converter. Design avoids difficult brazing operation. Includes pair of mating flanged cups. Upper cup integral part of housing of thermoelectric converter, while lower cup integral part of plate supporting filled heat pipes. Heat pipes prefilled. Heat of welding applied around periphery of coupling, far enough from heat pipes so it would not degrade working fluid or create excessive vapor pressure in the pipes.

Nesmith, Bill J.

1991-01-01

38

Solar assisted heat pump heating system  

Microsoft Academic Search

A solar assisted heat pump fluid heating system capable of reliable operation at higher than normal ambient temperatures is disclosed. The system includes a collection of solar panels and primary fluid storage tanks having integral coiled heat exchangers interconnected and charged with heat transfer fluid to produce heat. Temperature sensors positioned at the panels and storage tanks transmit temperature signals

Pendergrass

1984-01-01

39

Design and Fabrication of a Stirling Engine Heat Exchanger Module with an Integral Heat Pipe.  

National Technical Information Service (NTIS)

The conceptual design of a free-piston Stirling Space Engine (SSE) intended for space power applications has been generated. The engine was designed to produce 25 kW of electric power with heat supplied by a nuclear reactor. A novel heat exchanger module ...

J. G. Schreiber

1988-01-01

40

Heat reclaimer  

SciTech Connect

A device for reclaiming heat from stove pipes and the like. A semi-circular shaped hollow enclosed housing with a highly thermal-conductive concave surface is mounted contactingly to surround approximately one-half of the circumference of the stove pipe. The concave surface is formed to contact the pipe at a maximum number of points along that surface. The hollow interior of the housing contains thin multi-surfaced projections which are integral with the concave surface and conductively transfer heat from the stove pipe and concave surface to heat the air in the housing. A fan blower is attached via an air conduit to an entrance opening in the housing. When turned on, the blower pushes the heated interior air out a plurality of air exit openings in the ends of the housing and brings in lower temperature outside air for heating.

Parham, F.

1985-04-09

41

Integrated heat exchanger design for a cryogenic storage tank  

NASA Astrophysics Data System (ADS)

Field demonstrations of liquid hydrogen technology will be undertaken for the proliferation of advanced methods and applications in the use of cryofuels. Advancements in the use of cryofuels for transportation on Earth, from Earth, or in space are envisioned for automobiles, aircraft, rockets, and spacecraft. These advancements rely on practical ways of storage, transfer, and handling of liquid hydrogen. Focusing on storage, an integrated heat exchanger system has been designed for incorporation with an existing storage tank and a reverse Brayton cycle helium refrigerator of capacity 850 watts at 20 K. The storage tank is a 125,000-liter capacity horizontal cylindrical tank, with vacuum jacket and multilayer insulation, and a small 0.6-meter diameter manway opening. Addressed are the specific design challenges associated with the small opening, complete modularity, pressure systems re-certification for lower temperature and pressure service associated with hydrogen densification, and a large 8:1 length-to-diameter ratio for distribution of the cryogenic refrigeration. The approach, problem solving, and system design and analysis for integrated heat exchanger are detailed and discussed. Implications for future space launch facilities are also identified. The objective of the field demonstration will be to test various zero-loss and densified cryofuel handling concepts for future transportation applications.

Fesmire, J. E.; Tomsik, T. M.; Bonner, T.; Oliveira, J. M.; Conyers, H. J.; Johnson, W. L.; Notardonato, W. U.

2014-01-01

42

An examination of heat rate improvements due to waste heat integration in an oxycombustion pulverized coal power plant  

NASA Astrophysics Data System (ADS)

Oxyfuel, or oxycombustion, technology has been proposed as one carbon capture technology for coal-fired power plants. An oxycombustion plant would fire coal in an oxidizer consisting primarily of CO2, oxygen, and water vapor. Flue gas with high CO2 concentrations is produced and can be compressed for sequestration. Since this compression generates large amounts of heat, it was theorized that this heat could be utilized elsewhere in the plant. Process models of the oxycombustion boiler, steam cycle, and compressors were created in ASPEN Plus and Excel to test this hypothesis. Using these models, heat from compression stages was integrated to the flue gas recirculation heater, feedwater heaters, and to a fluidized bed coal dryer. All possible combinations of these heat sinks were examined, with improvements in coal flow rate, Qcoal, net power, and unit heat rate being noted. These improvements would help offset the large efficiency impacts inherent to oxycombustion technology.

Charles, Joshua M.

43

Measured Space Conditioning and Water Heating Performance of a Ground-Source Integrated Heat Pump in a Residential Application  

SciTech Connect

In an effort to reduce residential building energy consumption, a ground-source integrated heat pump was developed to meet a home s entire space conditioning and water heating needs, while providing 50% energy savings relative to a baseline suite of minimum efficiency equipment. A prototype 7.0 kW system was installed in a 344 m2 research house with simulated occupancy in Oak Ridge, TN. The equipment was monitored from June 2012 through January 2013.

Munk, Jeffrey D [ORNL] [ORNL; Ally, Moonis Raza [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Gehl, Anthony C [ORNL] [ORNL

2014-01-01

44

Heat Without Heat  

NASA Astrophysics Data System (ADS)

Logic of the Second Law of Thermodynamics demands acquisition of naked entropy. Accordingly, the leanest liaison between systems is not a diathermic membrane, it is a purely informational tickler, leaking no appreciable energy. The subsystem here is a thermodynamic universe, which gets `heated' entropically, yet without gaining calories. Quantum Mechanics graciously supports that(Lubkin, E. and Lubkin, T., International Journal of Theoretical Physics,32), 933-943 (1993) (at a cost of about 1 bit) through entanglement---across this least permeable of membranes---with what is beyond that universe. Heat without heat(Also v. forthcoming Proceedings of the 4th Drexel University Conference of September 1994) is the aspirin for Boltzmann's headache, conserving entropy in mechanical isolation, even while increasing entropy in thermodynamic isolation.

Lubkin, Elihu

1997-04-01

45

Heat assisted magnetic recording with a fully integrated recording head  

NASA Astrophysics Data System (ADS)

Scaling the areal density, while maintaining a proper balance between media signal-to-noise, thermal stability and writability will soon require an alternative recording technology. Heat Assisted Magnetic Recording (HAMR) can achieve this balance by allowing high anisotropy media to be written by heating the media during the writing process (e.g. by laser light) to temporarily lower the anisotropy. Three major challenges of designing a HAMR head that tightly focuses light and collocates it with the magnetic field are discussed: 1) Magnetic Field Delivery, 2)Optical Delivery, and 3) Integration of Magnetic & Optical Field Delivery Components. Thousands of these HAMR heads were built into sliders and HGAs, and optical and scanning electron micrograph images are shown. Scanning near-field optical microscopy (SNOM) characterization of the HAMR head shows that the predicted ~?/4 full-width half-maximum (FWHM) spot size can be achieved using 488 nm light (124 nm was achieved). SNOM images also show that wafer level fabricated apertures were able to effectively eliminate sidelobes from the focused spot intensity profile. An MFM image of HAMR media shows that Non-HAMR (laser power off) was not able to write transitions in the HAMR specific media even at very high write currents, but transitions could be written using HAMR (laser power on), even at lower write currents. A cross-track profile is shown for a fully integrated HAMR head where the magnetic pole physical width is ~350 nm, but the written track is ~200nm, which demonstrates HAMR. A HAMR optimization contour shows that there is an optimum write current and laser power and that simply going to the highest write current and laser power does not lead to the best recording. Lastly, some prospects for advancing HAMR are given and a few key problems to be solved are mentioned.

Seigler, Michael A.; Challener, William A.; Gage, Edward; Gokemeijer, Nils; Lu, Bin; Pelhos, Kalman; Peng, Chubing; Rottmayer, Robert E.; Yang, Xiaomin; Zhou, Hua; Zhu, Xiaobin; Rausch, Tim

2007-07-01

46

Activated-Carbon Sorbent With Integral Heat-Transfer Device  

NASA Technical Reports Server (NTRS)

Prototype adsorption device used, for example, in adsorption heat pump, to store natural gas to power automobile, or to separate components of fluid mixtures. Device includes activated carbon held together by binder and molded into finned heat-transfer device providing rapid heating or cooling to enable rapid adsorption or desorption of fluids. Concepts of design and fabrication of device equally valid for such other highly thermally conductive devices as copper-finned tubes, and for such other high-surface-area sorbents as zeolites or silicates.

Jones, Jack A.; Yavrouian, Andre

1996-01-01

47

A meshless local boundary integral equation method for heat conduction analysis in nonhomogeneous solids  

Microsoft Academic Search

A local boundary integral equation method (LBIEM) with meshless approximation for heat conduction analysis in non?homogeneous solids is presented. A review of recent developments in advanced meshless LBIEM for 2?d, 3?d axisymmetric problems and microwave heating analysis is given. Both stationary and transient heat conduction problems are investigated in the paper. For transient problems both the Laplace transform technique and

Jan Sladek; Vladimir Sladek; Chuanzeng Zhang

2004-01-01

48

Internal-integral sodium return line for sodium heat engine  

DOEpatents

A thermoelectric generator device which converts heat energy to electrical energy. An alkali metal is used with a solid electrolyte and a portion of the return line for the alkali metal is located within the generator vacuum space.

Hunt, Thomas K. (Ann Arbor, MI)

1985-01-01

49

Heat Pipes  

ERIC Educational Resources Information Center

Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)

Lewis, J.

1975-01-01

50

Heat assisted magnetic recording with a fully integrated recording head  

Microsoft Academic Search

Scaling the areal density, while maintaining a proper balance between media signal-to-noise, thermal stability and writability will soon require an alternative recording technology. Heat Assisted Magnetic Recording (HAMR) can achieve this balance by allowing high anisotropy media to be written by heating the media during the writing process (e.g. by laser light) to temporarily lower the anisotropy. Three major challenges

Michael A. Seigler; William A. Challener; Edward Gage; Nils Gokemeijer; Bin Lu; Kalman Pelhos; Chubing Peng; Robert E. Rottmayer; Xiaomin Yang; Hua Zhou; Xiaobin Zhu; Tim Rausch

2007-01-01

51

Integrated Heat Assisted Magnetic Recording Head: Design and Recording Demonstration  

Microsoft Academic Search

Scaling the areal density, while maintaining a proper balance between media signal-to-noise ratio, thermal stability, and writability, will soon require an alternative recording technology. Heat assisted magnetic recording (HAMR) can achieve this balance by allowing high anisotropy media to be written by heating the media during the writing process (e.g., by laser light) to temporarily lower the anisotropy. Three major

Michael A. Seigler; William A. Challener; Edward Gage; Nils Gokemeijer; Ganping Ju; Bin Lu; Kalman Pelhos; Chubing Peng; Robert E. Rottmayer; Xiaomin Yang; Hua Zhou; Tim Rausch

2008-01-01

52

Fabrication of vapor-deposited micro heat pipe arrays as an integral part of semiconductor devices  

Microsoft Academic Search

Vapor-deposited micro heat pipe arrays (VDMHP) were fabricated as an integral part of semiconductor devices to act as efficient heat spreaders by reducing the thermal path between the heat sources and heat sink. Fabrication of the VDMHP was accomplished by first establishing a series of grooves in a silicon wafer. Orientation dependent etching (ODE) using a KOH-1-propanol-H2O solution on a

Amab K. Mallik; G. P. Peterson; Mark H. Weichold

1995-01-01

53

Vapor compression CuCl heat pump integrated with a thermochemical water splitting cycle  

Microsoft Academic Search

In this paper, the feasibility of using cuprous chloride (CuCl) as a working fluid in a new high temperature heat pump with vapor compression is analyzed. The heat pump is integrated with a copper–chlorine (Cu–Cl) thermochemical water splitting cycle for internal heat recovery, temperature upgrades and hydrogen production. The minimum temperature of heat supply necessary for driving the water splitting

C. Zamfirescu; G. F. Naterer; I. Dincer

2011-01-01

54

Parallel heat transport in integrable and chaotic magnetic fields  

SciTech Connect

The study of transport in magnetized plasmas is a problem of fundamental interest in controlled fusion, space plasmas, and astrophysics research. Three issues make this problem particularly challenging: (i) The extreme anisotropy between the parallel (i.e., along the magnetic field), {chi}{sub ||} , and the perpendicular, {chi}{sub Up-Tack }, conductivities ({chi}{sub ||} /{chi}{sub Up-Tack} may exceed 10{sup 10} in fusion plasmas); (ii) Nonlocal parallel transport in the limit of small collisionality; and (iii) Magnetic field lines chaos which in general complicates (and may preclude) the construction of magnetic field line coordinates. Motivated by these issues, we present a Lagrangian Green's function method to solve the local and non-local parallel transport equation applicable to integrable and chaotic magnetic fields in arbitrary geometry. The method avoids by construction the numerical pollution issues of grid-based algorithms. The potential of the approach is demonstrated with nontrivial applications to integrable (magnetic island), weakly chaotic (Devil's staircase), and fully chaotic magnetic field configurations. For the latter, numerical solutions of the parallel heat transport equation show that the effective radial transport, with local and non-local parallel closures, is non-diffusive, thus casting doubts on the applicability of quasilinear diffusion descriptions. General conditions for the existence of non-diffusive, multivalued flux-gradient relations in the temperature evolution are derived.

Castillo-Negrete, D. del; Chacon, L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-8071 (United States)

2012-05-15

55

Heat waves  

Microsoft Academic Search

The concept of transmission of heat by waves is reviewed and interpreted. The notion of an effective thermal conductivity, an effective heat capacity, and relaxation functions for heat and energy is introduced along lines used recently to describe the elastic response of viscous liquids. An annotated bibliography of the literature on heat waves, from the beginning until now, gives a

D. D. Joseph; Luigi Preziosi

1989-01-01

56

Heat pumps  

NSDL National Science Digital Library

What electric heating system is the most efficient in moderate climates? This reading, part of a series about the future of energy, introduces students to the modern heat pump. Students read about the efficiency of heat pumps and the three types currently being used in homes. A simple explanation of how a heat pump works is offered. Copyright 2005 Eisenhower National Clearinghouse

Project, Iowa P.

2004-01-01

57

Solar heating of integrated greenhouse-animal shelter systems  

SciTech Connect

An analytical procedure to determine the effectiveness of greenhouses as solar collectors was presented. This procedure was used to predict the effect of several construction parameters on solar radiation input to greenhouses. The orientation of the greenhouse was found to be the most effective construction parameter controlling solar radiation input to greenhouses. The effective albedo of the plant canopy was also found to be a significant factor. A new solar greenhouse design, suitable for high latitude regions was developed. The results showed that an internal solar collector could be incorporated as an integral part of the greenhouse design. The concept developed could be used as a free-standing greenhouse or in a combination with livestock building. The efficiency of the solar input was investigated for the conventional and the shed greenhouses, both as a free-standing unit and a greenhouse-animal shelter system, using computer simulation analyses. The results indicated that the efficiency of solar input is highly dependent on location; the effect of location on the shed type design is more profound. A typical case of a greenhouse-hog barn production system was investigated using computer simulation analyses. The results showed that such a food production system achieves a significant reduction in conventional fuel consumption due to both animal waste heat recovery and solar energy utilization.

Ben-Abdallah, N.

1983-01-01

58

Integrated Design and Manufacturing of Flat Miniature Heat Pipes Using Printed Circuit Board Technology  

Microsoft Academic Search

A novel, integrated approach in thermal management of electronic products, based on two-phase cooling, is presented. A flat miniature heat pipe, integrated inside the laminated structure of a printed circuit board (PCB) has been developed, based on mainstream PCB fabrication processes. Hot spots on the PCB, caused by heat dissipating components, can be cooled with relatively small temperature gradients across

Wessel W. Wits; Tom H. J. Vaneker

2010-01-01

59

Building with integral solar-heat storage--Starkville, Mississippi  

NASA Technical Reports Server (NTRS)

Column supporting roof also houses rock-storage bin of solar-energy system supplying more than half building space heating load. Conventional heaters supply hot water. Since bin is deeper and narrower than normal, individual pebble size was increased to keep airflow resistance at minimum.

1981-01-01

60

INTEGRATED CO2 HEAT PUMP SYSTEMS FOR SPACE HEATING AND HOT WATER HEATING IN LOW-ENERGY HOUSES AND PASSIVE HOUSES  

Microsoft Academic Search

Low-energy and passive houses are superinsulated and air-tight buildings where the space heating demand is considerably lower than that of buildings constructed in accordance with common buildings codes. Due to the low space heating demand, the annual heating demand for domestic hot water (DHW) typically consti- tutes 50 to 85% of the total annual heating demand in the residence. A

J. STENE

61

Integral equation solution for internal flow subjected to a variable heat transfer coefficient  

NASA Astrophysics Data System (ADS)

A solution methodology based on integral equations is presented for the problem of heat transfer to laminar duct flow subjected to an axial variation of the external heat transfer coefficient. The technique offers an efficient and accurate calculation procedure which combines standard analytical methods with a simple numerical integration. In order to examine the effect of external finning, results are calculated for the cases of a stepwise periodic and a harmonic variation of the heat transfer coefficient for both fully developed laminar flow and slug flow. The general procedure is applicable to a wide class of problems in heat and mass transfer involving variable boundary condition parameters.

Vick, B.; Beale, J. H.; Frankel, J. I.

1987-11-01

62

Modular, thermal bus-to-radiator integral heat exchanger design for Space Station Freedom  

NASA Technical Reports Server (NTRS)

The baseline concept is introduced for the 'integral heat exchanger' (IHX) which is the interface of the two-phase thermal bus with the heat-rejecting radiator panels. A direct bus-to-radiator heat-pipe integral connection replaces the present interface hardware to reduce the weight and complexity of the heat-exchange mechanism. The IHX is presented in detail and compared to the baseline system assuming certain values for heat rejection, mass per unit width, condenser capacity, contact conductance, and assembly mass. The spreadsheet comparison can be used to examine a variety of parameters such as radiator length and configuration. The IHX is shown to permit the reduction of panel size and system mass in response to better conductance and packaging efficiency. The IHX is found to be a suitable heat-rejection system for the Space Station Freedom because it uses present technology and eliminates the interface mechanisms.

Chambliss, Joe; Ewert, Michael

1990-01-01

63

Integrated exhaust and electrically heated particulate filter regeneration systems  

SciTech Connect

A system includes a particulate matter (PM) filter that includes multiple zones. An electrical heater includes heater segments that are associated with respective ones of the zones. The electrical heater is arranged upstream from and proximate with the PM filter. A post-fuel injection system injects fuel into at least one of a cylinder of an engine and an exhaust system. A control module is configured to operate in a first mode that includes activating the electrical heater to heat exhaust of the engine. The control module is also configured to operate in a second mode that includes activating the post-injection system to heat the exhaust. The control module selectively operates in at least one of the first mode and the second mode.

Gonze, Eugene V.; Paratore, Jr., Michael J.

2013-01-08

64

Exergetic analysis of solid oxide fuel cell and biomass gasification integration with heat pipes  

Microsoft Academic Search

This paper presents an exergetic analysis of a combined heat and power (CHP) system, integrating a near-atmospheric solid oxide fuel cell (SOFC) with an allothermal biomass fluidised bed steam gasification process. The gasification heat requirement is supplied to the fluidised bed from the SOFC stack through high-temperature sodium heat pipes. The CHP system was modelled in AspenPlus™ software including sub-models

L. Fryda; K. D. Panopoulos; J. Karl; E. Kakaras

2008-01-01

65

Counter flow cooling drier with integrated heat recovery  

DOEpatents

A drier apparatus for removing water or other liquids from various materials includes a mixer, drying chamber, separator and regenerator and a method for use of the apparatus. The material to be dried is mixed with a heated media to form a mixture which then passes through the chamber. While passing through the chamber, a comparatively cool fluid is passed counter current through the mixture so that the mixture becomes cooler and drier and the fluid becomes hotter and more saturated with moisture. The mixture is then separated into drier material and media. The media is transferred to the regenerator and heated therein by the hot fluid from the chamber and supplemental heat is supplied to bring the media to a preselected temperature for mixing with the incoming material to be dried. In a closed loop embodiment of the apparatus, the fluid is also recycled from the regenerator to the chamber and a chiller is utilized to reduce the temperature of the fluid to a preselected temperature and dew point temperature.

Shivvers, Steve D. (Prole, IA)

2009-08-18

66

Development of an integrated heat pipe-thermal storage system for a solar receiver  

NASA Technical Reports Server (NTRS)

An integrated heat pipe-thermal storage system was developed as part of the Organic Rankine Cycle Solar Dynamic Power System solar receiver for space station application. The solar receiver incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain thermal energy storage (TES) canisters within the vapor space with a toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe. Part of this thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of earth orbit, the stored energy in the TES units is transferred by the potassium vapor to the toluene heater tube. A developmental heat pipe element was constructed that contains axial arteries and a distribution wick connecting the toluene heater and the TES units to the solar insolation surface of the heat pipe. Tests were conducted to demonstrate the heat pipe, TES units, and the heater tube operation. The heat pipe element was operated at design input power of 4.8 kW. Thermal cycle tests were conducted to demonstrate the successful charge and discharge of the TES units. Axial power flux levels up to 15 watts/sq cm were demonstrated and transient tests were conducted on the heat pipe element. Details of the heat pipe development and test procedures are presented.

Keddy, E.; Sena, J. Tom; Merrigan, M.; Heidenreich, Gary; Johnson, Steve

1988-01-01

67

Development of an integrated heat pipe-thermal storage system for a solar receiver  

NASA Astrophysics Data System (ADS)

An integrated heat pipe-thermal storage system was developed as part of the Organic Rankine Cycle Solar Dynamic Power System solar receiver for space station application. The solar receiver incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain thermal energy storage (TES) canisters within the vapor space with a toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe. Part of this thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of earth orbit, the stored energy in the TES units is transferred by the potassium vapor to the toluene heater tube. A developmental heat pipe element was constructed that contains axial arteries and a distribution wick connecting the toluene heater and the TES units to the solar insolation surface of the heat pipe. Tests were conducted to demonstrate the heat pipe, TES units, and the heater tube operation. The heat pipe element was operated at design input power of 4.8 kW. Thermal cycle tests were conducted to demonstrate the successful charge and discharge of the TES units. Axial power flux levels up to 15 watts/sq cm were demonstrated and transient tests were conducted on the heat pipe element. Details of the heat pipe development and test procedures are presented.

Keddy, E.; Sena, J. Tom; Merrigan, M.; Heidenreich, Gary; Johnson, Steve

1988-06-01

68

Integrative analysis of the heat shock response in Aspergillus fumigatus  

PubMed Central

Background Aspergillus fumigatus is a thermotolerant human-pathogenic mold and the most common cause of invasive aspergillosis (IA) in immunocompromised patients. Its predominance is based on several factors most of which are still unknown. The thermotolerance of A. fumigatus is one of the traits which have been assigned to pathogenicity. It allows the fungus to grow at temperatures up to and above that of a fevered human host. To elucidate the mechanisms of heat resistance, we analyzed the change of the A. fumigatus proteome during a temperature shift from 30°C to 48°C by 2D-fluorescence difference gel electrophoresis (DIGE). To improve 2D gel image analysis results, protein spot quantitation was optimized by missing value imputation and normalization. Differentially regulated proteins were compared to previously published transcriptome data of A. fumigatus. The study was augmented by bioinformatical analysis of transcription factor binding sites (TFBSs) in the promoter region of genes whose corresponding proteins were differentially regulated upon heat shock. Results 91 differentially regulated protein spots, representing 64 different proteins, were identified by mass spectrometry (MS). They showed a continuous up-, down- or an oscillating regulation. Many of the identified proteins were involved in protein folding (chaperones), oxidative stress response, signal transduction, transcription, translation, carbohydrate and nitrogen metabolism. A correlation between alteration of transcript levels and corresponding proteins was detected for half of the differentially regulated proteins. Interestingly, some previously undescribed putative targets for the heat shock regulator Hsf1 were identified. This provides evidence for Hsf1-dependent regulation of mannitol biosynthesis, translation, cytoskeletal dynamics and cell division in A. fumigatus. Furthermore, computational analysis of promoters revealed putative binding sites for an AP-2alpha-like transcription factor upstream of some heat shock induced genes. Until now, this factor has only been found in vertebrates. Conclusions Our newly established DIGE data analysis workflow yields improved data quality and is widely applicable for other DIGE datasets. Our findings suggest that the heat shock response in A. fumigatus differs from already well-studied yeasts and other filamentous fungi.

2010-01-01

69

Multicriteria aided design of integrated heating-cooling energy systems in buildings.  

PubMed

This paper presents an analysis of the possible application of integrated heating-cooling systems in buildings. The general algorithm of integrated heating-cooling system design aid was formulated. The evaluation criteria of technically acceptable variants were defined. Fossil fuel energy consumption, carbon dioxide emission, investment, and total exploitation cost were identified as the most important factors describing the considered decision problem. The multicriteria decision aid method ELECTRE III was proposed as the decision tool for the choice of the most compromised variant. The proposed method was used for a case study calculation-the choice of an integrated heating-cooling system for an office building. PMID:20842935

Mróz, Tomasz M

2010-08-01

70

a Conceptual Model of Integrating Sensor Network and Radiative Heat Transfer Equation for Ethylene Furnace  

Microsoft Academic Search

A conceptual model of integrating the sensor network and the radiative heat transfer equation is developed and presented in this paper. The idea is to present possible deployment of sensor networks in the Ethylene furnace so that valuable input in the form of boundary value can be generated in order to produce intensity distribution and heat flux distribution. Once the

Z. Abal Abas; S. Salleh; A. S. Hassan Basari; Nuzulha Khilwani Ibrahim

2010-01-01

71

A CONCEPTUAL MODEL OF INTEGRATING SENSOR NETWORK AND RADIATIVE HEAT TRANSFER EQUATION FOR ETHYLENE FURNACE  

Microsoft Academic Search

A conceptual model of integrating the sensor network and the radiative heat transfer equation is developed and presented in this paper. The idea is to present possible deployment of sensor networks in the Ethylene furnace so that valuable input in the form of boundary value can be generated in order to produce intensity distribution and heat flux distribution. Once the

Z. Abal Abas; S. Salleh; A. S. Hassan Basari; Nuzulha Khilwani Ibrahim

2010-01-01

72

Transient heat conduction analysis in functionally graded materials by the meshless local boundary integral equation method  

Microsoft Academic Search

Advanced computational method for transient heat conduction analysis in continuously nonhomogeneous functionally graded materials (FGM) is proposed. The method is based on the local boundary integral equations with moving least square approximation of the temperature and heat flux. The initial-boundary value problem is solved by the Laplace transform technique. Both Papoulis and Stehfest algorithms are applied for the numerical Laplace

J. Sladek; V. Sladek; Ch. Zhang

2003-01-01

73

Heat transfer in microwave heating  

NASA Astrophysics Data System (ADS)

Heat transfer is considered as one of the most critical issues for design and implement of large-scale microwave heating systems, in which improvement of the microwave absorption of materials and suppression of uneven temperature distribution are the two main objectives. The present work focuses on the analysis of heat transfer in microwave heating for achieving highly efficient microwave assisted steelmaking through the investigations on the following aspects: (1) characterization of microwave dissipation using the derived equations, (2) quantification of magnetic loss, (3) determination of microwave absorption properties of materials, (4) modeling of microwave propagation, (5) simulation of heat transfer, and (6) improvement of microwave absorption and heating uniformity. Microwave heating is attributed to the heat generation in materials, which depends on the microwave dissipation. To theoretically characterize microwave heating, simplified equations for determining the transverse electromagnetic mode (TEM) power penetration depth, microwave field attenuation length, and half-power depth of microwaves in materials having both magnetic and dielectric responses were derived. It was followed by developing a simplified equation for quantifying magnetic loss in materials under microwave irradiation to demonstrate the importance of magnetic loss in microwave heating. The permittivity and permeability measurements of various materials, namely, hematite, magnetite concentrate, wüstite, and coal were performed. Microwave loss calculations for these materials were carried out. It is suggested that magnetic loss can play a major role in the heating of magnetic dielectrics. Microwave propagation in various media was predicted using the finite-difference time-domain method. For lossy magnetic dielectrics, the dissipation of microwaves in the medium is ascribed to the decay of both electric and magnetic fields. The heat transfer process in microwave heating of magnetite, which is a typical magnetic dielectric, was simulated by using an explicit finite-difference approach. It is demonstrated that the heat generation due to microwave irradiation dominates the initial temperature rise in the heating and the heat radiation heavily affects the temperature distribution, giving rise to a hot spot in the predicted temperature profile. Microwave heating at 915 MHz exhibits better heating homogeneity than that at 2450 MHz due to larger microwave penetration depth. To minimize/avoid temperature nonuniformity during microwave heating the optimization of object dimension should be considered. The calculated reflection loss over the temperature range of heating is found to be useful for obtaining a rapid optimization of absorber dimension, which increases microwave absorption and achieves relatively uniform heating. To further improve the heating effectiveness, a function for evaluating absorber impedance matching in microwave heating was proposed. It is found that the maximum absorption is associated with perfect impedance matching, which can be achieved by either selecting a reasonable sample dimension or modifying the microwave parameters of the sample.

Peng, Zhiwei

74

Heat Pipes  

NASA Technical Reports Server (NTRS)

Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.

1996-01-01

75

Heat Pipes  

NASA Technical Reports Server (NTRS)

Phoenix Refrigeration Systems, Inc.'s heat pipe addition to the Phoenix 2000, a supermarket rooftop refrigeration/air conditioning system, resulted from the company's participation in a field test of heat pipes. Originally developed by NASA to control temperatures in space electronic systems, the heat pipe is a simple, effective, heat transfer system. It has been used successfully in candy storage facilities where it has provided significant energy savings. Additional data is expected to fully quantify the impact of the heat pipes on supermarket air conditioning systems.

1991-01-01

76

Heat-pump-centered integrated community energy systems: system development summary  

SciTech Connect

An introduction to district heating systems employing heat pumps to enable use of low-temperature energy sources is presented. These systems operate as thermal utilities to provide space heating and may also supply space cooling, service-water heating, and other thermal services. Otherwise-wasted heat from industrial and commercial processes, natural sources including solar and geothermal heat, and heat stored on an annual cycle from summer cooling may be effectively utilized by the systems described. These sources are abundant, and their use would conserve scarce resources and reduce adverse environmental impacts. More than one-quarter of the energy consumed in the United States is used to heat and cool buildings and to heat service water. Natural gas and oil provide approximately 83% of this energy. The systems described show potential to reduce net energy consumption for these services by 20 to 50% and to allow fuel substitution with less-scarce resources not practical in smaller, individual-building systems. Seven studies performed for the system development phase of the Department of Energy's Heat-Pump-Centered Integrated Community Energy Systems Project and to related studies are summarized. A concluding chapter tabulates data from these separately published studies.

Calm, J.M.

1980-02-01

77

Process for producing an activated carbon adsorbent with integral heat transfer apparatus  

NASA Technical Reports Server (NTRS)

A process for producing an integral adsorbent-heat exchanger apparatus useful in ammonia refrigerant heat pump systems. In one embodiment, the process wets an activated carbon particles-solvent mixture with a binder-solvent mixture, presses the binder wetted activated carbon mixture on a metal tube surface and thereafter pyrolyzes the mixture to form a bonded activated carbon matrix adjoined to the tube surface. The integral apparatus can be easily and inexpensively produced by the process in large quantities.

Jones, Jack A. (Inventor); Yavrouian, Andre H. (Inventor)

1996-01-01

78

Heated Goggles  

NASA Technical Reports Server (NTRS)

The electrically heated ski goggles shown incorporate technology similar to that once used in Apollo astronauts' helmet visors, and for the same reason-providing fogfree sight in an activity that demands total vision. Defogging is accomplished by applying heat to prevent moisture condensation. Electric heat is supplied by a small battery built into the h goggles' headband. Heat is spread across the lenses by means of an invisible coating of electrically conductive metallic film. The goggles were introduced to the market last fall. They were designed by Sierracin Corporation, Sylmar, California, specialists in the field of heated transparent materials. The company produces heated windshields for military planes and for such civil aircraft as the Boeing 747, McDonnell Douglas DC-10 and Lockheed L-1011 TriStar.

1978-01-01

79

Roles of DNA repair and membrane integrity in heat resistance of Deinococcus radiodurans.  

PubMed

To study the effects of heat shock on Deinococcus radiodurans and the role of DNA repair in high temperature resistance, different strains of D. radiodurans (wild type, recA, irrE, and pprA) were treated with temperatures ranging from 40 to 100 °C under wet and dry conditions. The mutant strains were more sensitive to wet heat of ?60 °C and dry heat of ?80 °C than the wild type. Both wild-type and DNA repair-deficient strains were much more resistant to high temperatures when exposed in the dried state as opposed to cells in suspension. Molecular staining techniques with the wild-type strain revealed that cells in the dried state were able to retain membrane integrity after drying and subsequent heat exposure, while heat-exposed cells in suspension showed significant loss of membrane integrity and respiration activity. The results suggest that the repair of DNA damage (e.g., DNA double-strand breaks by RecA and PprA) is essential after treatment with wet heat at temperatures >60 °C and dry heat >80 °C, and the ability of D. radiodurans to stabilize its plasma membrane during dehydration might represent one aspect in the protection of dried cells from heat-induced membrane damage. PMID:23011749

Bauermeister, Anja; Hahn, Claudia; Rettberg, Petra; Reitz, Günther; Moeller, Ralf

2012-11-01

80

Heat Transfer  

NSDL National Science Digital Library

Students explore heat transfer and energy efficiency using the context of energy efficient houses. They gain a solid understanding of the three types of heat transfer: radiation, convection and conduction, which are explained in detail and related to the real world. They learn about the many ways solar energy is used as a renewable energy source to reduce the emission of greenhouse gasses and operating costs. Students also explore ways in which a device can capitalize on the methods of heat transfer to produce a beneficial result. They are given the tools to calculate the heat transferred between a system and its surroundings.

Integrated Teaching And Learning Program

81

Heat pipes. [technology utilization  

NASA Technical Reports Server (NTRS)

The development and use of heat pipes are described, including space requirements and contributions. Controllable heat pipes, and designs for automatically maintaining a selected constant temperature, are discussed which would add to the versatility and usefulness of heat pipes in industrial processing, manufacture of integrated circuits, and in temperature stabilization of electronics.

1975-01-01

82

Reducing CO2 emissions and energy consumption of heat-integrated distillation systems.  

PubMed

Distillation systems are energy and power intensive processes and contribute significantly to the greenhouse gases emissions (e.g. carbon dioxide). Reducing CO2 emissions is an absolute necessity and expensive challenge to the chemical process industries in orderto meetthe environmental targets as agreed in the Kyoto Protocol. A simple model for the calculation of CO2 emissions from heat-integrated distillation systems is introduced, considering typical process industry utility devices such as boilers, furnaces, and turbines. Furnaces and turbines consume large quantities of fuels to provide electricity and process heats. As a result, they produce considerable amounts of CO2 gas to the atmosphere. Boilers are necessary to supply steam for heating purposes; besides, they are also significant emissions contributors. The model is used in an optimization-based approach to optimize the process conditions of an existing crude oil atmospheric tower in order to reduce its CO2 emissions and energy demands. It is also applied to generate design options to reduce the emissions from a novel internally heat-integrated distillation column (HIDiC). A gas turbine can be integrated with these distillation systems for larger emissions reduction and further energy savings. Results show that existing crude oil installations can save up to 21% in energy and 22% in emissions, when the process conditions are optimized. Additionally, by integrating a gas turbine, the total emissions can be reduced further by 48%. Internal heat-integrated columns can be a good alternative to conventional heat pump and other energy intensive close boiling mixtures separations. Energy savings can reach up to 100% with respect to reboiler heat requirements. Emissions of these configurations are cut down by up to 83%, compared to conventional units, and by 36%, with respect to heat pump alternatives. Importantly, cost savings and more profit are gained in parallel to emissions minimization. PMID:16190250

Gadalla, Mamdouh A; Olujic, Zarko; Jansens, Peter J; Jobson, Megan; Smith, Robin

2005-09-01

83

Integrated Thermal Protection Systems and Heat Resistant Structures  

NASA Technical Reports Server (NTRS)

In the early stages of NASA's Exploration Initiative, Snecma Propulsion Solide was funded under the Exploration Systems Research & Technology program to develop a CMC heatshield, a deployable decelerator, and an ablative heat shield for reentry vehicles. Due to changes within NASA's Exploration Initiative, this task was cancelled in early FY06. This paper will give an overview of the work that was accomplished prior to cancellation. The Snecma team consisted of MT Aerospace, Germany, and Materials Research & Design (MR&D), NASA Langley, NASA Dryden, and NASA Ames in the United States. An Apollo-type capsule was chosen as the reference vehicle for the work. NASA Langley generated the trajectory and aerothermal loads. Snecma and MT Aerospace began the design of a ceramic aft heatshield (CAS) utilizing C/SiC panels as the capsule heatshield. MR&D led the design of a C/SiC deployable decelerator, NASA Ames led the characterization of several ablators, NASA Dryden led the development of a heath management system and the high temperature structures testing, and NASA Langley led the insulation characterization. Though the task was pre-maturely cancelled, a significant quantity of work was accomplished.

Pichon, Thierry; Lacoste, Marc; Barreteau, R.; Glass, David E.

2006-01-01

84

Heat Problems.  

ERIC Educational Resources Information Center

Heat problems and heat cramps related to jogging can be caused by fluid imbalances, medications, dietary insufficiency, vomiting or diarrhea, among other factors. If the condition keeps reoccurring, the advice of a physician should be sought. Some preventive measures that can be taken include: (1) running during the cooler hours of the day; (2)…

Connors, G. Patrick

85

Heat illness.  

PubMed

A 17-year-old girl collapsed during a field hockey practice on a hot August afternoon, apparently suffering from heat illness, which is responsible for about 5,000 deaths annually. A panel of experts explores this girl's case, discusses heat illness in general, and makes recommendations about diagnosis, prevention, and treatment. PMID:2398843

Buss, D D; Kelly, J M; Reinholtz, G D; Roberts, W O; Fischer, D A

1990-08-01

86

Development of an integrated heat pipe-thermal storage system for a solar receiver  

NASA Technical Reports Server (NTRS)

The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

1987-01-01

87

Development of an integrated heat pipe-thermal storage system for a solar receiver  

NASA Astrophysics Data System (ADS)

The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

1987-07-01

88

From time temperature integrator kinetics to time temperature integrator tolerance levels: heat-treated milk.  

PubMed

Six milk compounds were studied as potential intrinsic time temperature integrators (TTIs) for the assessment of heat-treated milk. These include the enzymes alkaline phosphatase and lactoperoxidase, the whey protein beta-lactoglobulin and the chemical compounds hydroxymethylfurfural, lactulose and furosine. In previous research the inactivation/denaturation/formation kinetics of these compounds were analyzed under isothermal and nonisothermal conditions and evaluated for variability of the milk composition. The present paper focuses on the implementation of the TTIs. TTIs are validated with respect to microbiological indices and quality attributes, and a quantitative relationship between the denaturation, inactivation or formation of the TTIs and technological processes is established by construction of general time temperature tolerance (TTT) diagrams. In these diagrams temperature time combinations are presented, which lead to the same formation, inactivation or denaturation of TTIs, or result in the same level of microbiological destruction or quality degradation of the product. TTT-diagrams are very informative since they allow visualization of the impact of a thermal process on milk and evaluation of criteria for evaluating milk authenticity (conformity of the product with the terminology applied). Moreover, the optimum combination of temperature and time of heating may be readily deduced from these diagrams. PMID:14763817

Claeys, Wendie L; Smout, Chantal; Van Loey, Ann M; Hendrickx, Marc E

2004-01-01

89

A solar cooker using vacuum-tube collectors with integrated heat pipes  

Microsoft Academic Search

A solar cooking system is described which consists of a vacuum-tube collector with integrated long heat pipes directly leading to the oven plate. The cooker was tested during several clear days in Marburg (latitude 51°). The heat-up times were measured under cold- and hot-start conditions. Detailed temperature distributions and their time dependences were measured. The maximum temperature obtained in a

A. Balzar; P. Stumpf; S. Eckhoff; H. Ackermann; M. Grupp

1996-01-01

90

Transient heat conduction analysis using the MLPG method and modified precise time step integration method  

Microsoft Academic Search

The meshless local Petrov–Galerkin (MLPG) method in conjunction with the modified precise time step integration method in the time domain is proposed for transient heat conduction analysis in this paper. The MLPG method is often referred to as a truly meshless method because it requires no elements or background cells for either field interpolation or background integration. Local weak forms

Qing-Hua Li; Shen-Shen Chen; Guang-Xiao Kou

2011-01-01

91

Transient performance evaluation of an integrated heat pipe-thermal storage system  

NASA Technical Reports Server (NTRS)

Transient performance tests of an integrated heat pipe-thermal storage system have been conducted. This system was developed as a part of an Organic Rankine Cycle-Solar Dynamic Power System receiver for future power systems. The integrated system consists of potassium heat pipe elements that incorporate thermal energy storage canisters within the vapor space and an organic fluid (toluene) heater tube used as the condenser region of the heat pipe. The transient performance tests determined the operating characteristics and power input limits of the integrated heat pipe-thermal storage unit under conditions corresponding to re-acquisition of the sun during emergence from eclipse conditions and to the initial start-up of the solar dynamic power system. The tests demonstrated that the heat pipe-thermal storage element is not limited under conditions corresponding to emergence from eclipse during normal orbital operations and the heat pipe will successfully start-up from the frozen condition with full input power at the onset. Details of the test procedures and results of the tests are presented in this paper.

Keddy, E.; Sena, J. T.; Merrigan, M.; Heidenreich, Gary; Johnson, Steve

1988-01-01

92

Calculation of heat capacities of light and heavy water by path-integral molecular dynamics  

NASA Astrophysics Data System (ADS)

As an application of atomistic simulation methods to heat capacities, path-integral molecular dynamics has been used to calculate the constant-volume heat capacities of light and heavy water in the gas, liquid, and solid phases. While the classical simulation based on conventional molecular dynamics has estimated the heat capacities too high, the quantum simulation based on path-integral molecular dynamics has given reasonable results based on the simple point-charge/flexible potential model. The calculated heat capacities (divided by the Boltzmann constant) in the quantum simulation are 3.1 in the vapor H2O at 300 K, 6.9 in the liquid H2O at 300 K, and 4.1 in the ice Ih H2O at 250 K, respectively, which are comparable to the experimental data of 3.04, 8.9, and 4.1, respectively. The quantum simulation also reproduces the isotope effect. The heat capacity in the liquid D2O has been calculated to be 10% higher than that of H2O, while it is 13% higher in the experiment. The results demonstrate that the path-integral simulation is a promising approach to quantitatively evaluate the heat capacities for molecular systems, taking account of quantum-mechanical vibrations as well as strongly anharmonic motions.

Shiga, Motoyuki; Shinoda, Wataru

2005-10-01

93

Calculation of heat capacities of light and heavy water by path-integral molecular dynamics.  

PubMed

As an application of atomistic simulation methods to heat capacities, path-integral molecular dynamics has been used to calculate the constant-volume heat capacities of light and heavy water in the gas, liquid, and solid phases. While the classical simulation based on conventional molecular dynamics has estimated the heat capacities too high, the quantum simulation based on path-integral molecular dynamics has given reasonable results based on the simple point-charge/flexible potential model. The calculated heat capacities (divided by the Boltzmann constant) in the quantum simulation are 3.1 in the vapor H2O at 300 K, 6.9 in the liquid H2O at 300 K, and 4.1 in the ice Ih H2O at 250 K, respectively, which are comparable to the experimental data of 3.04, 8.9, and 4.1, respectively. The quantum simulation also reproduces the isotope effect. The heat capacity in the liquid D2O has been calculated to be 10% higher than that of H2O, while it is 13% higher in the experiment. The results demonstrate that the path-integral simulation is a promising approach to quantitatively evaluate the heat capacities for molecular systems, taking account of quantum-mechanical vibrations as well as strongly anharmonic motions. PMID:16223309

Shiga, Motoyuki; Shinoda, Wataru

2005-10-01

94

Heat collector  

DOEpatents

A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

Merrigan, M.A.

1981-06-29

95

Heat collector  

DOEpatents

A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

Merrigan, Michael A. (Santa Cruz, NM)

1984-01-01

96

Heat-of-Reaction Chemical Heat Pumps.  

National Technical Information Service (NTIS)

Chemical heat pumps are mechanically driven heat pumps with working fluids that undergo chemical changes or are heat-driven heat pumps in which either the driver (heat engine) or heat pump utilizes a reactive working fluid. As such, chemical heat pumps ca...

C. Bliem L. Kirol

1988-01-01

97

Development of a Variable-Speed Residential Air-Source Integrated Heat Pump  

SciTech Connect

A residential air-source integrated heat pump (AS-IHP) is under development in partnership with a U.S. manufacturer. A nominal 10.6 kW (3-ton) cooling capacity variable-speed unit, the system provides both space conditioning and water heating. This multi-functional unit can provide domestic water heating (DWH) in either full condensing (FC) (dedicated water heating or simultaneous space cooling and water heating) or desuperheating (DS) operation modes. Laboratory test data were used to calibrate a vapor-compression simulation model for each mode of operation. The model was used to optimize the internal control options for efficiency while maintaining acceptable comfort conditions and refrigerant-side pressures and temperatures within allowable operating envelopes. Annual simulations were performed with the AS-IHP installed in a well-insulated house in five U.S. climate zones. The AS-IHP is predicted to use 45 to 60% less energy than a DOE minimum efficiency baseline system while meeting total annual space conditioning and water heating loads. Water heating energy use is lowered by 60 to 75% in cold to warmer climates, respectively. Plans are to field test the unit in Knoxville, TN.

Rice, C Keith [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL; Munk, Jeffrey D [ORNL] [ORNL; Ally, Moonis Raza [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL

2014-01-01

98

Electrically heated liquid tank employing heat pipe heat transfer means  

Microsoft Academic Search

The heating apparatus for applying heat to the interior of a chamber includes a modular, removable, electrical, heat-producing unit and a heat pipe mountable in a wall of the chamber with one end of the pipe arranged to receive heat from the electrical heat producing unit exterior of the housing and with another end of the pipe constructed and arranged

Shutt

1978-01-01

99

Integration of Radioisotope Heat Source with Stirling Engine and Cooler for Venus Internal-Structure Mission  

SciTech Connect

The primary mission goal is to perform long-term seismic measurements on Venus, to study its largely unknown internal structure. The principal problem is that most payload components cannot long survive Venus's harsh environment, 90 bars at 500 degrees C. To meet the mission life goal, such components must be protected by a refrigerated payload bay. JPL Investigators have proposed a mission concept employing a lander with a spherical payload bay cooled to 25 degrees C by a Stirling cooler powered by a radioisotope-heated Sitrling engine. To support JPL's mission study, NASA/Lewis and MTI have proposed a conceptual design for a hydraulically coupled Stirling engine and cooler, and Fairchild Space - with support of the Department of Energy - has proposed a design and integration scheme for a suitable radioisotope heat source. The key integration problem is to devise a simple, light-weight, and reliable scheme for forcing the radioisotope decay heat to flow through the Stirling engine during operation on Venus, but to reject that heat to the external environment when the Stirling engine and cooler are not operating (e.g., during the cruise phase, when the landers are surrounded by heat shields needed for protection during subsequent entry into the Venusian atmosphere.) A design and integration scheme for achieving these goals, together with results of detailed thermal analyses, are described in this paper. There are 7 copies in the file.

Schock, Alfred

1993-10-01

100

Coal Heating District Heating Plants.  

National Technical Information Service (NTIS)

The Elektrisitetsforsyningens Forskningsinstitutt (EFI) has considered the Norwegian district heating potential. The remaining demand is 7 TWh and parts of it may be covered by coal when local energy resources are utilized to a reasonable extent. Two plan...

J. Hustad G. Syvertsen P. Walde

1983-01-01

101

A comparative performance rating for an integrated solar collector\\/storage vessel with inner sleeves to increase heat retention  

Microsoft Academic Search

Integral Collector\\/Storage (ICS) solar water heating systems suffer substantial heat loss during periods of low insolation or at night. Methods to reduce aperture heat loss include moveable insulated lids\\/shutters, transparent insulating glazing materials and selective glazing\\/absorber coatings. All of these approaches involve trade-offs with reduction in performance and\\/or an increase in cost. A novel ICS vessel design to mitigate heat

M Smyth; P. C Eames; B Norton

1999-01-01

102

Ultrananocrystalline diamond tip integrated onto a heated atomic force microscope cantilever.  

PubMed

We report a wear-resistant ultrananocrystalline (UNCD) diamond tip integrated onto a heated atomic force microscope (AFM) cantilever and UNCD tips integrated into arrays of heated AFM cantilevers. The UNCD tips are batch-fabricated and have apex radii of approximately 10 nm and heights up to 7 ?m. The solid-state heater can reach temperatures above 600 °C and is also a resistive temperature sensor. The tips were shown to be wear resistant throughout 1.2 m of scanning on a single-crystal silicon grating at a force of 200 nN and a speed of 10 ?m s(-1). Under the same conditions, a silicon tip was completely blunted. We demonstrate the use of these heated cantilevers for thermal imaging in both contact mode and intermittent contact mode, with a vertical imaging resolution of 1.9 nm. The potential application to nanolithography was also demonstrated, as the tip wrote hundreds of polyethylene nanostructures. PMID:23149947

Kim, Hoe Joon; Moldovan, Nicolaie; Felts, Jonathan R; Somnath, Suhas; Dai, Zhenting; Jacobs, Tevis D B; Carpick, Robert W; Carlisle, John A; King, William P

2012-12-14

103

Zero-G Condensing Heat Exchanger with Integral Disinfection  

NASA Technical Reports Server (NTRS)

The system that operates in a zero gravity environment and has an integral ozone generating capability is disclosed. The system contributes to the control of metabolic water vapors in the air, and also provided disinfection of any resulting condensate within the system, as well as disinfection of the air stream that flows throughout the disclosed system.

Burke, Kenneth A. (Inventor)

2012-01-01

104

Intrinsic time temperature integrators for heat treatment of milk  

Microsoft Academic Search

This paper reviews the available research information on intrinsic time temperature integrators (TTIs) for thermally processed milk. These are specific indicators present or formed in milk that allow direct and quantitative measurement of the impact of the process without knowledge of the actual thermal history. General principles concerning the characterization of intrinsic TTIs as well as the applicability and limitations

Wendie L Claeys; Ann M Van Loey; Marc E Hendrickx

2002-01-01

105

Identification of heat risk patterns in the U.S. National Capital Region by integrating heat stress and related vulnerability.  

PubMed

The increase in the number and severity of weather extremes (including excessive heat) potentially associated with climate change has highlighted the needs for research into risk assessment and risk reduction measures. Extreme heat events, the focus of this paper, have been consistently reported as the leading cause of weather-related mortality in the United States in recent years. In order to fully understand impact potentials and analyze risk in its individual components both the spatially and temporally varying patterns of heat and the multidimensional characteristics of vulnerability have to be considered. In this paper we present a composite index aggregating these factors to assess heat related risk for the U.S. National Capital Region in 2010. The study reveals how risk patterns are in part driven by the geographic variations of vulnerability, generally showing a clear difference between high-risk urban areas and wide areas of low risk in the suburban and rural environments. This pattern is particularly evident for the core center of the study area around the District of Columbia, which is largely characterized by high index values despite not having experienced the peak of the heat stress as compared to other regions in the metropolitan area. The article aims to set a framework for local-level heat stress risk assessment that can provide valuable input and decision support for climate adaptation planning as well as emergency managers aiming at risk reduction and optimization of resource distribution. PMID:23603733

Aubrecht, Christoph; Özceylan, Dilek

2013-06-01

106

Heat Pipes  

NASA Technical Reports Server (NTRS)

Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than $57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was $28,706, and that figures out to a cost reduction.

1990-01-01

107

MODELING THE LINE-OF-SIGHT INTEGRATED EMISSION IN THE CORONA: IMPLICATIONS FOR CORONAL HEATING  

SciTech Connect

One of the outstanding problems in all of space science is uncovering how the solar corona is heated to temperatures greater than 1 MK. Though studied for decades, one of the major difficulties in solving this problem has been unraveling the line-of-sight (LOS) effects in the observations. The corona is optically thin, so a single pixel measures counts from an indeterminate number (perhaps tens of thousands) of independently heated flux tubes, all along that pixel's LOS. In this paper we model the emission in individual pixels imaging the active region corona in the extreme ultraviolet. If LOS effects are not properly taken into account, erroneous conclusions regarding both coronal heating and coronal dynamics may be reached. We model the corona as an LOS integration of many thousands of completely independently heated flux tubes. We demonstrate that despite the superposition of randomly heated flux tubes, nanoflares leave distinct signatures in light curves observed with multi-wavelength and high time cadence data, such as those data taken with the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. These signatures are readily detected with the time-lag analysis technique of Viall and Klimchuk in 2012. Steady coronal heating leaves a different and equally distinct signature that is also revealed by the technique.

Viall, Nicholeen M.; Klimchuk, James A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2013-07-10

108

Heat, Energy, and Order, Part Two of an Integrated Science Sequence, Student Guide, 1970 Edition.  

ERIC Educational Resources Information Center

Part two of the first year in the Portland Project, a three-year high school integrated science curriculum, is contained in this student guide. This volume, one of four parts in the year course, involves activities relating to what is considered the most powerful unifying concept in science: energy. The macroscopic aspects of heat as embodied in…

Portland Project Committee, OR.

109

Air-Source Integrated Heat Pump for Near-Zero Energy Houses: Technology Status Report.  

National Technical Information Service (NTIS)

This report documents the development of an air-source integrated heat pump (AS-IHP) through the third quarter of FY2007. It describes the design, analyses and testing of the AS-IHP, and provides performance specifications for a field test prototype and p...

K. C. Rice R. W. Murphy V. D. Baxter W. G. Craddick

2007-01-01

110

Transient heat conduction analysis using the MLPG method and modified precise time step integration method  

NASA Astrophysics Data System (ADS)

The meshless local Petrov-Galerkin (MLPG) method in conjunction with the modified precise time step integration method in the time domain is proposed for transient heat conduction analysis in this paper. The MLPG method is often referred to as a truly meshless method because it requires no elements or background cells for either field interpolation or background integration. Local weak forms are developed using weighted residual method locally from the partial differential equation of transient heat conduction. In order to simplify the treatment of essential boundary conditions, the natural neighbour interpolation (NNI) is employed for the construction of trial functions. Moreover, the three-node triangular FEM shape functions are taken as test functions to reduce the order of integrands involved in domain integrals. The semi-discrete heat conduction equation is solved numerically with modified precise time step integration method in the time domain. The availability and accuracy of the present method for transient heat conduction analysis are tested through numerical examples.

Li, Qing-Hua; Chen, Shen-Shen; Kou, Guang-Xiao

2011-04-01

111

Development of an integrated heat pipe-thermal storage system for a solar receiver  

SciTech Connect

The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. Sundstrand Corporation is developing a ORC-SDPS candidate for the Space Station that uses toluene as the organic fluid and LiOH as the TES material. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube. 3 refs., 8 figs.

Keddy, E.S.; Sena, J.T.; Merrigan, M.A.; Heidenreich, G.; Johnson, S.

1987-01-01

112

Fuel processing in integrated micro-structured heat-exchanger reactors  

Microsoft Academic Search

Micro-structured fuel processors are under development at IMM for different fuels such as methanol, ethanol, propane\\/butane (LPG), gasoline and diesel. The target application are mobile, portable and small scale stationary auxiliary power units (APU) based upon fuel cell technology. The key feature of the systems is an integrated plate heat-exchanger technology which allows for the thermal integration of several functions

G. Kolb; J. Schürer; D. Tiemann; M. Wichert; R. Zapf; V. Hessel; H. Löwe

2007-01-01

113

Heat exchanger  

SciTech Connect

A heat exchanger having primary and secondary conduits in heat-exchanging relationship is described comprising: at least one serpentine tube having parallel sections connected by reverse bends, the serpentine tube constituting one of the conduits; a group of open-ended tubes disposed adjacent to the parallel sections, the open-ended tubes constituting the other of the conduits, and forming a continuous mass of contacting tubes extending between and surrounding the serpentine tube sections; and means securing the mass of tubes together to form a predetermined cross-section of the entirety of the mass of open-ended tubes and tube sections.

Drury, C.R.

1988-02-02

114

Finite element methods for integrated aerodynamic heating analysis  

NASA Technical Reports Server (NTRS)

This report gives a description of the work which has been undertaken during the second year of a three year research program. The objectives of the program are to produce finite element based procedures for the solution of the large scale practical problems which are of interest to the Aerothermal Loads Branch (ALB) at NASA Langley Research Establishment. The problems of interest range from Euler simulations of full three dimensional vehicle configurations to local analyses of three dimensional viscous laminar flow. Adaptive meshes produced for both steady state and transient problems are to be considered. An important feature of the work is the provision of specialized techniques which can be used at ALB for the development of an integrated fluid/thermal/structural modeling capability.

Morgan, K.; Peraire, J.

1991-01-01

115

Lunar base heat pump  

NASA Technical Reports Server (NTRS)

A heat pump is a device which elevates the temperature of a heat flow by a means of an energy input. By doing this, the heat pump can cause heat to transfer faster from a warm region to a cool region, or it can cause heat to flow from a cool region to a warmer region. The second case is the one which finds vast commercial applications such as air conditioning, heating, and refrigeration. Aerospace applications of heat pumps include both cases. The NASA Johnson Space Center is currently developing a Life Support Systems Integration Facility (LSSIF, previously SIRF) to provide system-level integration, operational test experience, and performance data that will enable NASA to develop flight-certified hardware for future planetary missions. A high lift heat pump is a significant part of the TCS hardware development associated with the LSSIF. The high lift heat pump program discussed here is being performed in three phases. In Phase 1, the objective is to develop heat pump concepts for a lunar base, a lunar lander, and for a ground development unit for the SIRF. In Phase 2, the design of the SIRF ground test unit is being performed, including identification and evaluation of safety and reliability issues. In Phase 3, the SIRF unit will be manufactured, tested, and delivered to the NASA Johnson Space Center.

Goldman, Jeffrey H.; Tetreault, R.; Fischbach, D.; Walker, D.

1994-01-01

116

Heat recovery from industry  

SciTech Connect

Heating and/or cooling are often important parts of industrial processes. Well-designed systems have integrated heating and cooling processes, although in many instances this cannot be done. In such cases the heat subtracted by the cooling process is rejected to the environment. Energy experts pay much attention to the efficient use of energy and utilization of waste energy world-wide. There are several good examples for both process integration and heat recovery. But there are also many cases both in Hungary and elsewhere in which, due to the special economic environment, distorted energy-price structure, or lack of motivation, not enough care was taken regarding this issue or potential projects were not implemented. This article presents two cases where waste heat of industrial processes could be used for district heating. This would result in reduced fuel consumption and decreased heat pollution. The examples also demonstrate how waste-heat sources can be interconnected and integrated to district heating systems. Considerable changes in the economic environment and environmental protection legislation as well as novel technologies are needed to encourage the exploration and utilization of such opportunities in Hungary and other countries.

Zebik, A.; Baliko, S. [Technical Univ. Budapest (Hungary). Dept. of System and Control Engineering; Mont, J. [Oklahoma State Univ., Stillwater, OK (United States)

1997-12-31

117

Radiant heating  

Microsoft Academic Search

Compared with previous designs, this radiant heater is simpler to construct, operates better in dusty atmospheres, and has a cooler frame that allows it to be placed closer to the materials being heated. Ideal for textile or paper drying, the heater has a conduit for noncombustible gas that extends around the panel, discharging the cool gas to keep the combustion

1981-01-01

118

Flash Heating  

NASA Astrophysics Data System (ADS)

Meteorites contain millimeter-sized objects called chondrules. They were melted in the solar nebula, the cloud of gas and dust in which the Sun and planets formed. Numerous experiments on rock powders have been done to understand the melting process and the cooling rates chondrules experienced. Most meteorite specialists believe that chondrules formed by flash heating, with almost instantaneous melting, though the length of time they remained molten is uncertain. Can conventional laboratory furnaces heat rock powders rapidly enough to flash melt them? Susan Maharaj and Roger Hewins (Rutgers University, New Brunswick) tested this idea by inserting tiny wires of pure elements (which have precise melting temperatures) into compressed rock powders about 3.5 mm in diameter, and placing the samples into a furnace heated to a range of temperatures. They found that at 1600 C, a sample took only six seconds to reach 1538 C. When placed into a furnace at 1500 C, samples took ten seconds to reach 1495 C. This shows that the flash heating process can be studied in conventional laboratory furnaces.

Taylor, G. J.

2000-03-01

119

Cooling and heating system utilizing solar heat  

SciTech Connect

A cooling and heating system utilizing solar heat comprises a heat collector for heating a circulating heat medium with solar heat, an absorption refrigerator operable with the heat medium heated by the heat collector and serving as a generating heat source to provide a chilled medium, and an air-conditioning unit for circulating the chilled medium or the heated medium alternatively therethrough to cool or heat the space to be airconditioned. The system further comprises a bypass line provided with an auxiliary refrigerator of the dual-effect type and connected to an intermediate portion of a line extending from the absorption refrigerator to the air-conditioning unit for supplying chilled medium or the heated medium to the unit. Change -over means is provided for passing the chilled medium or the heated medium through the bypass line.

Katayama, K.; Yukimachi, K.

1981-05-26

120

Numerical investigation of premixed combustion in a porous burner with integrated heat exchanger  

NASA Astrophysics Data System (ADS)

In this paper, we perform a numerical analysis of a two-dimensional axisymmetric problem arising in premixed combustion in a porous burner with integrated heat exchanger. The physical domain consists of two zones, porous and heat exchanger zones. Two dimensional Navier-Stokes equations, gas and solid energy equations, and chemical species transport equations are solved and heat release is described by a multistep kinetics mechanism. The solid matrix is modeled as a gray medium, and the finite volume method is used to solve the radiative transfer equation to calculate the local radiation source/sink in the solid phase energy equation. Special attention is given to model heat transfer between the hot gas and the heat exchanger tube. Thus, the corresponding terms are added to the energy equations of the flow and the solid matrix. Gas and solid temperature profiles and species mole fractions on the burner centerline, predicted 2D temperature fields, species concentrations and streamlines are presented. Calculated results for temperature profiles are compared to experimental data. It is shown that there is good agreement between the numerical solutions and the experimental data and it is concluded that the developed numerical program is an excellent tool to investigate combustion in porous burner.

Farzaneh, Meisam; Shafiey, Mohammad; Ebrahimi, Reza; Shams, Mehrzad

2012-07-01

121

Geothermal heating  

SciTech Connect

The aim of the study is to demonstrate the viability of geothermal heating projects in energy and economic terms and to provide nomograms from which an initial estimate may be made without having to use data-processing facilities. The effect of flow rate and temperature of the geothermal water on drilling and on the network, and the effect of climate on the type of housing are considered.

Aureille, M.

1982-01-01

122

Heat Transfer  

NSDL National Science Digital Library

In this inquiry activity students explore how heat transfers from one substance to another This inquiry activity was developed by a K-12 science teacher in the American Physiological SocietyÃÂs 2006 Frontiers in Physiology Program. The NSES Standards addressed by this activity are current as of the year of development. For more information on the Frontiers in Physiology Program, please visit www.frontiersinphys.org.

Ms. Leslie Van (Montgomery Blair High School)

2006-04-01

123

Geothermal district heating systems  

NASA Astrophysics Data System (ADS)

Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

Budney, G. S.; Childs, F.

1982-06-01

124

Infrared radiant heating  

Microsoft Academic Search

Retrofitting convective forced air heating systems with infrared (IR) systems can save as much as 50 percent of the total heating bill. Infrared heating is more efficient for two reasons: it can be directed to heat only occupied space; and it does not heat the air in a space, it only heats people and objects. Infrared heating works best where

S. Cannon; M. Rocha

1996-01-01

125

Industrial Waste Heat for Greenhouse Heating.  

National Technical Information Service (NTIS)

The economical conditions of utilizing industrial waste heat for greenhouse heating has been investigated. The investment cost and yearly operational costs of greenhouses and heating systems have been calculated as a function of the temperature of waste h...

S. E. Ransmark

1983-01-01

126

Exergetic modeling and assessment of solar assisted domestic hot water tank integrated ground-source heat pump systems for residences  

Microsoft Academic Search

The present study deals with the exergetic modeling and performance evaluation of solar assisted domestic hot water tank integrated ground-source heat pump (GSHP) systems for residences for the first time to the best of the author's knowledge. The model is applied to a system, which mainly consists of (i) a water-to-water heat pump unit (ii) a ground heat exchanger system

Arif Hepbasli

2007-01-01

127

Heat pipes in modern heat exchangers  

Microsoft Academic Search

Heat pipes are very flexible systems with regard to effective thermal control. They can easily be implemented as heat exchangers inside sorption and vapour-compression heat pumps, refrigerators and other types of heat transfer devices. Their heat transfer coefficient in the evaporator and condenser zones is 103–105 W\\/m2K, heat pipe thermal resistance is 0.01–0.03 K\\/W, therefore leading to smaller area and

Leonard L. Vasiliev

2005-01-01

128

Hydride heat pump with heat regenerator  

NASA Technical Reports Server (NTRS)

A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

Jones, Jack A. (Inventor)

1991-01-01

129

Integrated Heat Recovery/Power Burner for Cogeneration Systems. Final Report, April 15, 1985-February 28, 1992.  

National Technical Information Service (NTIS)

The objective of Integrated Heat Recovery/Power Burner for Cogeneration Systems was to design, fabricate and test an advanced heat recovery unit (HRU) for use on exhaust of gas-fired reciprocating engine-generators in the 50-500 kW range. The HRU emphasiz...

A. J. Kubasco

1992-01-01

130

Inhomogeneous temperature problems inside a Li/SOCl2 cell - Homogenization by integrated heat pipes  

SciTech Connect

The effect of the temperature gradient on the electrical capacity of the lithium/thionyl chloride (Li/SOCl2) cells and the dependence of internal heat generation on the temperature level were investigated by studying the thermal behavior of a cell constituted by a number of couples stacken in a stainless steel cylinder during a discharge profile. It is shown that the temperature gradient between couples affected the depth of discharge, indicating that this gradient must be limited to prevent discrepancy in couple's voltage and inversion phenomenon. It was found that a cooling concept based on integrated heat pipes is effective in reducing the temperature gradient and in yielding homogeneous cell behavior in overdischarge. 6 refs.

Lefriec, C.; Suleiman, A.; Alexandre, A.

1992-01-01

131

Fabrication and development of several heat pipe honeycomb sandwich panel concepts. [airframe integrated scramjet engine  

NASA Technical Reports Server (NTRS)

The feasibility of fabricating and processing liquid metal heat pipes in a low mass honeycomb sandwich panel configuration for application on the NASA Langley airframe-integrated Scramjet engine was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts was evaluated within constraints dictated by existing manufacturing technology and equipment. The chosen design consists of an all-stainless steel structure, sintered screen facesheets, and two types of core-ribbon; a diffusion bonded wire mesh and a foil-screen composite. Cleaning, fluid charging, processing, and process port sealing techniques were established. The liquid metals potassium, sodium and cesium were used as working fluids. Eleven honeycomb panels 15.24 cm X 15.24 cm X 2.94 cm were delivered to NASA Langley for extensive performance testing and evaluation; nine panels were processed as heat pipes, and two panels were left unprocessed.

Tanzer, H. J.

1982-01-01

132

a Conceptual Model of Integrating Sensor Network and Radiative Heat Transfer Equation for Ethylene Furnace  

NASA Astrophysics Data System (ADS)

A conceptual model of integrating the sensor network and the radiative heat transfer equation is developed and presented in this paper. The idea is to present possible deployment of sensor networks in the Ethylene furnace so that valuable input in the form of boundary value can be generated in order to produce intensity distribution and heat flux distribution. Once the location of sensor deployment has been recommended, the mesh at the physical space between the furnace wall and the reactor tube is constructed. The paper concentrates only at 2D model with only 1 U-bend reactor tube in the ethylene furnace as an initial phase of constructing a complete simulation in real furnace design.

Abas, Z. Abal; Salleh, S.; Basari, A. S. Hassan; Ibrahim, Nuzulha Khilwani

2010-11-01

133

Printed Circuit Boards with Integrated Heat Carrier Channels for Deep Geothermal Resources  

NASA Astrophysics Data System (ADS)

The exploration of deep geothermal resources is still very expensive. A large amount of these costs is caused by the drilling process. The high price results from a high failure risk, slow drilling progress and a large amount of manual work. To develop deep heat mining to a sizeable contribution to the European energy portfolio, the exploration process has to become a lot cheaper. One step to achieve lower costs is to monitor and automate the drilling process. Therefore, electronic components such as sensors and data processing units must be integrated into the Bottom Hole Assembly (BHA). The integration of electronics into the BHA faces the challenge of high ambient temperatures. The project "Packaging of Electronic Components for High Temperature Applications" within the "Geothermal Energy and High Performance-Drilling Collaborative Research Program (gebo)" develops a system of heat carrier channels integrated in printed circuit boards (PCB). These channels can be perfused with fluids such as water, oil or gas and provide high heat convection rates. Such PCBs will be able to withstand high ambient temperatures up to 250 °C. We have simulated, manufactured and are currently testing prototype boards with integrated heat carrier channels featuring a thickness of only 1.6 mm. As a simulation scenario, we chose a board measuring 25 mm x 100 mm, dimensions suitable for integration into a BHA. An ambient temperature of 250 °C was used. The simulation results presented in this contribution illustrate that cooling of the whole board as well as cooling of hotspots is possible. The cooling channel layout being the key for high convection rates was meticulously studied and optimized. Parameters such as necessary flow rate and fluid pressure were adjusted accordingly. Preliminary experiments validate the demonstrated and discussed simulation results. With the proposed cooling system, it is possible to integrate microelectronic components into the BHA for drilling applications in hot rock. Sensors and data processing units for measurement and logging can be used while drilling, thus providing a better data source for automation, navigation and planning. This will help to optimize drilling costs and to minimize failure risks.

Krühn, T.; Overmeyer, L.

2012-04-01

134

Heat Stress Reduces Intestinal Barrier Integrity and Favors Intestinal Glucose Transport in Growing Pigs  

PubMed Central

Excessive heat exposure reduces intestinal integrity and post-absorptive energetics that can inhibit wellbeing and be fatal. Therefore, our objectives were to examine how acute heat stress (HS) alters intestinal integrity and metabolism in growing pigs. Animals were exposed to either thermal neutral (TN, 21°C; 35–50% humidity; n?=?8) or HS conditions (35°C; 24–43% humidity; n?=?8) for 24 h. Compared to TN, rectal temperatures in HS pigs increased by 1.6°C and respiration rates by 2-fold (P<0.05). As expected, HS decreased feed intake by 53% (P<0.05) and body weight (P<0.05) compared to TN pigs. Ileum heat shock protein 70 expression increased (P<0.05), while intestinal integrity was compromised in the HS pigs (ileum and colon TER decreased; P<0.05). Furthermore, HS increased serum endotoxin concentrations (P?=?0.05). Intestinal permeability was accompanied by an increase in protein expression of myosin light chain kinase (P<0.05) and casein kinase II-? (P?=?0.06). Protein expression of tight junction (TJ) proteins in the ileum revealed claudin 3 and occludin expression to be increased overall due to HS (P<0.05), while there were no differences in claudin 1 expression. Intestinal glucose transport and blood glucose were elevated due to HS (P<0.05). This was supported by increased ileum Na+/K+ ATPase activity in HS pigs. SGLT-1 protein expression was unaltered; however, HS increased ileal GLUT-2 protein expression (P?=?0.06). Altogether, these data indicate that HS reduce intestinal integrity and increase intestinal stress and glucose transport.

Pearce, Sarah C.; Mani, Venkatesh; Boddicker, Rebecca L.; Johnson, Jay S.; Weber, Thomas E.; Ross, Jason W.; Rhoads, Robert P.; Baumgard, Lance H.; Gabler, Nicholas K.

2013-01-01

135

Heat stress reduces intestinal barrier integrity and favors intestinal glucose transport in growing pigs.  

PubMed

Excessive heat exposure reduces intestinal integrity and post-absorptive energetics that can inhibit wellbeing and be fatal. Therefore, our objectives were to examine how acute heat stress (HS) alters intestinal integrity and metabolism in growing pigs. Animals were exposed to either thermal neutral (TN, 21°C; 35-50% humidity; n=8) or HS conditions (35°C; 24-43% humidity; n=8) for 24 h. Compared to TN, rectal temperatures in HS pigs increased by 1.6°C and respiration rates by 2-fold (P<0.05). As expected, HS decreased feed intake by 53% (P<0.05) and body weight (P<0.05) compared to TN pigs. Ileum heat shock protein 70 expression increased (P<0.05), while intestinal integrity was compromised in the HS pigs (ileum and colon TER decreased; P<0.05). Furthermore, HS increased serum endotoxin concentrations (P=0.05). Intestinal permeability was accompanied by an increase in protein expression of myosin light chain kinase (P<0.05) and casein kinase II-? (P=0.06). Protein expression of tight junction (TJ) proteins in the ileum revealed claudin 3 and occludin expression to be increased overall due to HS (P<0.05), while there were no differences in claudin 1 expression. Intestinal glucose transport and blood glucose were elevated due to HS (P<0.05). This was supported by increased ileum Na(+)/K(+) ATPase activity in HS pigs. SGLT-1 protein expression was unaltered; however, HS increased ileal GLUT-2 protein expression (P=0.06). Altogether, these data indicate that HS reduce intestinal integrity and increase intestinal stress and glucose transport. PMID:23936392

Pearce, Sarah C; Mani, Venkatesh; Boddicker, Rebecca L; Johnson, Jay S; Weber, Thomas E; Ross, Jason W; Rhoads, Robert P; Baumgard, Lance H; Gabler, Nicholas K

2013-01-01

136

Segmented heat exchanger  

DOEpatents

A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

Baldwin, Darryl Dean (Lafayette, IN); Willi, Martin Leo (Dunlap, IL); Fiveland, Scott Byron (Metamara, IL); Timmons, Kristine Ann (Chillicothe, IL)

2010-12-14

137

Dual source heat pump  

DOEpatents

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

1982-01-01

138

Geothermal heat pumps for heating and cooling  

NASA Astrophysics Data System (ADS)

Naval Facilities Engineering Service Center (NFESC) has been tasked by Naval Shore Facilities Energy Office to evaluate the NAS Patuxent River ground-source heat pump (GHP) installation. A large part of a building's energy consumption consists of heating and air conditioning for occupant comfort. The space heating requirements are normally met by fossil-fuel-fired equipment or electric resistance heating. Cooling is provided by either air conditioners or heat pumps, both using electricity as an energy source.

Garg, Suresh C.

1994-03-01

139

Integrated simulations of implosion, electron transport, and heating for direct-drive fast-ignition targets  

SciTech Connect

A thorough understanding of future integrated fast-ignition experiments combining compression and heating of high-density thermonuclear fuel requires hybrid (fluid+particle) simulations of the implosion and ignition process. Different spatial and temporal scales need to be resolved to model the entire fast-ignition experiment. The two-dimensional (2D) axisymmetric hydrocode DRACO[P. B. Radha et al., Phys. Plasmas 12, 056307 (2005)] and the 2D/three-dimensional hybrid particle-in-cell code LSP[D. R. Welch et al., Nucl. Instrum. Methods Phys. Res. A 464, 134 (2001)] have been integrated to simulate the implosion and heating of direct-drive, fast-ignition fusion targets. DRACO includes the physics required to simulate compression, ignition, and burn of fast-ignition targets. LSP simulates the transport of hot electrons from the place where they are generated to the dense fuel core where their energy is absorbed. The results from integrated simulations of cone-in-shell CD targets designed for fast-ignition experiments on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997); C. Stoeckl et al., Fusion Sci. Technol. 49, 367 (2006)] are presented. Target heating and neutron yields are computed. The results from LSP simulations of electron transport in solid-density plastic targets are also presented. They confirm an increase in the electron divergence angle with the laser intensity in the current experiments. The self-generated resistive magnetic field is found to collimate the hot-electron beam and increase the coupling efficiency of hot electrons with the target. Resistive filamentation of the hot-electron beam is also observed.

Solodov, A. A.; Anderson, K. S.; Betti, R.; Gotcheva, V.; Myatt, J.; Delettrez, J. A.; Skupsky, S.; Theobald, W.; Stoeckl, C. [Fusion Science Center and Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States)

2009-05-15

140

Ceramics in heat exchangers  

Microsoft Academic Search

This book presents the papers given at a conference on the testing of ceramics for heat exchangers. Topics considered at the conference included advanced heat-transfer systems, heat recovery equipment, air-to-air heat exchangers, fluidized bed heat-recovery boilers, industrial heat recovery, potential materials, materials development and evaluation, chemical vapor deposition, product testing, fracture properties, and the durability of silicon carbide heat-exchanger tubes

B. D. Foster; J. B. Patton

1984-01-01

141

High heat flux single phase heat exchanger  

NASA Technical Reports Server (NTRS)

This paper presents the results obtained to date in a program to develop a high heat flux, single-phase heat exchanger for spacecraft thermal management. The intended application is a net generation interface heat exchanger to couple the crew module water thermal bus to the two-phase ammonia main thermal bus in the Space Station Freedom. The large size of the interface heat exchanger is dictated by the relatively poor water-side heat transfer characteristics. The objective of this program is to develop a single-phase heat transfer approach which can achieve heat fluxes and heat transfer coefficients comparable to those of the evaporation ammonia side. A new heat exchanger concept has been developed to meet these objecties. The main feature of this heat exchanger is that it can achieve very high heat fluxes with a pressure drop one to two orders of magnitude lower than those of previous microchannel or jet impingement high heat flux heat exchangers. This paper describes proof-of-concept experiments performed in air and water and presents analytical model of the heat exchanger.

Valenzuela, Javier A.; Izenson, Michael G.

1990-01-01

142

Heat Pipe With Interrupted Slot  

NASA Technical Reports Server (NTRS)

Newer version of heat pipe slot interrupted by plug or, if heat pipe is cast, by bridge of heat-pipe material cast integrally across groove. Small barrier assists in priming heat pipe. Vapor and noncondensible gas still accumulates in liquid channel at evaporator before or during startup, but barrier keeps liquid out of small part of slot at bubble. Dry part of slot allows bubble to escape into vapor channel, making room for liquid to move in during startup.

Brown, Richard F.; Kosson, Robert L.; Edelstein, Fred

1994-01-01

143

Heating Up  

NSDL National Science Digital Library

This interactive, online activity introduces the idea that everything emits electromagnetic radiation, including students. Students discover how the light emitted from an object (a robot) changes as the object is heated. A graph shows the amount of light the robot emits in each wavelength region as the robot reaches higher temperatures. Students are challenged to relate the peak of the emitted light from the robot to the color it appears, thus connecting the temperature of an object with the color of light it emits. Students apply this information by plotting the peak wavelengths of four stars of their choice, and then determine the temperature of each. Upon completion of this activity, students will have identified peak wavelengths from graphical data and applied this concept to determine the relationship between temperature and star color. Students may complete this activity independently or in small groups. Detailed teacher pages, identified as Teaching Tips on the title page of the activity, provide science background information, lesson plan ideas, related resources, and alignment with national education standards. This activity is part of the online exploration "Star Light, Star Bright" that focuses on the electromagnetic spectrum and that is available on the Amazing Space website.

144

Process Integration Study of the Decatur HFCS Plant for American Fructose Company, Decatur, AL [Advanced Industrial Heat Pump Applications and Evaluations  

SciTech Connect

This work has carried out in two phases: Phase 1, identification of opportunities for heat pumps in industrial applications and Phase 2; evaluation of heat pumps in industrial applications. In Phase 1, pinch analysis was applied to several industrial sites to identify the best opportunities for heat pumping and other forms of heat integration. In Phase 2, more detailed analyses were undertaken, including the evaluation of a heat pump installed as a recommendation of Phase 1.

Eastwood, A.

1989-11-10

145

An integrated heat pipe-thermal storage design for a solar receiver  

NASA Astrophysics Data System (ADS)

Light-weight heat pipe wall elements that incorporate a thermal storage subassembly within the vapor space are being developed as part of the Organic Rankine Cycle Solar Dynamic Power System (ORC-SDPS) receiver for the Space Station application. The operating temperature of the heat pipe elements is in the 770 to 810 K range with a design power throughput of 4.8 kW per pipe. The total heat pipe length is 1.9 M. The Rankine cycle boiler heat transfer surfaces are positioned within the heat pipe vapor space, providing a relatively constant temperature input to the vaporizer. The heat pipe design employs axial arteries and distribution wicked thermal storage units with potassium as the working fluid. Performance predictions for this configuration have been conducted and the design characterized as a function of artery geometry, distribution wick thickness, porosity, pore size, and permeability.

Keddy, E.; Sena, J. T.; Woloshun, K.; Merrigan, M. A.; Heidenreich, G.

146

Multiple source heat pump  

DOEpatents

A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

Ecker, Amir L. (Duncanville, TX)

1983-01-01

147

Solar heating system  

SciTech Connect

A solar heating system comprises a heat accumulating structure for heating both air and water in which both the heated air and water are directed to an object to be heated such as a commercial building or private residence. The heat accumulating structure is below ground and includes a magnifying glass forming the roof thereof and protruding above ground, the magnifying glass concentrating the rays of the sun into the heat accumulating structure which includes a lower portion containing water and an air space thereabove. The solar heating system includes a piping arrangement whereby heated water can be directed to the object to be heated and piped away. Likewise a heat trunk line and return air line is included for utilizing the heated air formed in the air space of the heat accumulating structure.

Hall, R.L.

1982-03-16

148

Nitinol heat engines  

Microsoft Academic Search

Heat engines have recently been developed which utilize the remarkable properties of a nickel-titanium alloy called Nitinol to convert heat into mechanical energy. The design, principles of operation, and performance characteristics of a small prototype Nitinol heat engine are described. Emphasis is placed on the description of a simple heat engine invented by the author, in which a specially heat-treated

A. D. Johnson

1975-01-01

149

Mantle heat flow  

Microsoft Academic Search

A map of the heat flux out of the earth's mantle has been prepared by subtracting the heat flow arising in the earth's crust from the surface heat flow. In continental areas the crustal contribution of the enriched zone is determined from the parameters of the linear heat flow-heat production relationship q0 = q* + bA0 in areas where such

Henry N. Pollack; David S. Chapman

1977-01-01

150

Heat pipe technology  

NASA Technical Reports Server (NTRS)

A bibliography of heat pipe technology to provide a summary of research projects conducted on heat pipes is presented. The subjects duscussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design and fabrication, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

1972-01-01

151

Heat pump defrosting operation  

Microsoft Academic Search

This patent describes improvements to the method of defrosting operation of a heat pump having a compressor, an interior heat exchanger, an exterior heat exchanger, an exterior fan for moving exterior air past the exterior heat exchanger, and a thermostatic control means for cycling the compressor on and off in accordance with heating demand. The improvement comprises: operating the exterior

M. Levine; J. Russo; V. Rigotti; N. Skogler

1990-01-01

152

Heat pump defrosting operation  

Microsoft Academic Search

This patent describes an improvement to the method of defrosting operation of a heat pump having a compressor, an interior heat exchanger, an exterior heat exchanger, an exterior fan for moving exterior air past the exterior heat enchanger, and a thermostatic control means for cycling the compressor on and off in accordance with heating demand. The improvement comprises: measuring at

M. Levine; J. Russo; V. Rigotti; N. Skogler

1990-01-01

153

Waste heat recovery device  

Microsoft Academic Search

A cascade heat exchange system is described in which the heat given off in condensing a superheated vaporized refrigerant is used to vaporize carbon dioxide and to add sensible heat to a water system. The superheated discharge vapor of a refrigeration system is pumped into the shell side of a heat exchange vessel, where evaporative tube bundles absorb heat from

Barrow

1980-01-01

154

Heat pipe radiator. [for spacecraft waste heat rejection  

NASA Technical Reports Server (NTRS)

A 15,000 watt spacecraft waste heat rejection system utilizing heat pipe radiator panels was investigated. Of the several concepts initially identified, a series system was selected for more in-depth analysis. As a demonstration of system feasibility, a nominal 500 watt radiator panel was designed, built and tested. The panel, which is a module of the 15,000 watt system, consists of a variable conductance heat pipe (VCHP) header, and six isothermalizer heat pipes attached to a radiating fin. The thermal load to the VCHP is supplied by a Freon-21 liquid loop via an integral heat exchanger. Descriptions of the results of the system studies and details of the radiator design are included along with the test results for both the heat pipe components and the assembled radiator panel. These results support the feasibility of using heat pipes in a spacecraft waste heat rejection system.

Swerdling, B.; Alario, J.

1973-01-01

155

Heat-of-Reaction Chemical Heat Pumps: Possible Configurations.  

National Technical Information Service (NTIS)

Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, heat driven heat pumps in which either heat engine or heat pump working fluid is reactive, are considere...

L. D. Kirol

1986-01-01

156

Heat pipe with embedded wick structure  

DOEpatents

A heat pipe has an embedded wick structure that maximizes capillary pumping capability. Heat from attached devices such as integrated circuits evaporates working fluid in the heat pipe. The vapor cools and condenses on a heat dissipation surface. The condensate collects in the wick structure, where capillary pumping returns the fluid to high heat areas. 7 figs.

Adkins, D.R.; Shen, D.S.; Tuck, M.R.; Palmer, D.W.; Grafe, V.G.

1998-06-23

157

Heat stress and reduced plane of nutrition decreases intestinal integrity and function in pigs.  

PubMed

Heat stress can compromise intestinal integrity and induce leaky gut in a variety of species. Therefore, the objectives of this study were to determine if heat stress (HS) directly or indirectly (via reduced feed intake) increases intestinal permeability in growing pigs. We hypothesized that an increased heat-load causes physiological alterations to the intestinal epithelium, resulting in compromised barrier integrity and altered intestinal function that contributes to the overall severity of HS-related illness. Crossbred gilts (n=48, 43±4 kg BW) were housed in constant climate controlled rooms in individual pens and exposed to 1) thermal neutral (TN) conditions (20°C, 35-50% humidity) with ad libitum intake, 2) HS conditions (35°C, 20-35% humidity) with ad libitum feed intake, or 3) pair-fed in TN conditions (PFTN) to eliminate confounding effects of dissimilar feed intake. Pigs were sacrificed at 1, 3, or 7 d of environmental exposure and jejunum samples were mounted into modified Ussing chambers for assessment of transepithelial electrical resistance (TER) and intestinal fluorescein isothiocyanate (FITC)-labeled lipopolysaccharide (LPS) permeability (expressed as apparent permeability coefficient, APP). Further, gene and protein markers of intestinal integrity and stress were assessed. Irrespective of d of HS exposure, plasma endotoxin levels increased 45% (P<0.05) in HS compared with TN pigs, while jejunum TER decreased 30% (P<0.05) and LPS APP increased 2-fold (P<0.01). Furthermore, d 7 HS pigs tended (P=0.06) to have increased LPS APP (41%) compared with PFTN controls. Lysozyme and alkaline phosphatase activity decreased (46 and 59%, respectively; P<0.05) over time in HS pigs, while the immune cell marker, myeloperoxidase activity, was increased (P<0.05) in the jejunum at d 3 and 7. These results indicate that both HS and reduced feed intake decrease intestinal integrity and increase endotoxin permeability. We hypothesize that these events may lead to increased inflammation, which might contribute to reduced pig performance during warm summer months. PMID:23989867

Pearce, S C; Mani, V; Weber, T E; Rhoads, R P; Patience, J F; Baumgard, L H; Gabler, N K

2013-11-01

158

Critical heat flux around strongly heated nanoparticles.  

PubMed

We study heat transfer from a heated nanoparticle into surrounding fluid using molecular dynamics simulations. We show that the fluid next to the nanoparticle can be heated well above its boiling point without a phase change. Under increasing nanoparticle temperature, the heat flux saturates, which is in sharp contrast with the case of flat interfaces, where a critical heat flux is observed followed by development of a vapor layer and heat flux drop. These differences in heat transfer are explained by the curvature-induced pressure close to the nanoparticle, which inhibits boiling. When the nanoparticle temperature is much larger than the critical fluid temperature, a very large temperature gradient develops, resulting in close to ambient temperature just a radius away from the particle surface. The behavior reported allows us to interpret recent experiments where nanoparticles can be heated up to the melting point, without observing boiling of the surrounding liquid. PMID:19391744

Merabia, Samy; Keblinski, Pawel; Joly, Laurent; Lewis, Laurent J; Barrat, Jean-Louis

2009-02-01

159

Heat flow through extended surface heat exchangers  

SciTech Connect

Contents of this book include the one-dimensional analysis of fin assembly heat transfer, the two dimensional analysis of fin assembly heat transfer, the analysis of fin radiation and the applicability of the perfect contact assumption.

Manzoor, M.

1984-01-01

160

Stirling and Vuilleumier heat pumps  

SciTech Connect

The book discuses the design, application, and performance evaluation of integrated engine-refrigerator heat pumps and provides an overview of heat pump theory, including a unique comparative analysis of six integrated Stirling and Vuilleumier heat pumps and their advantages in applications. It also evaluates the effect of key components on performance; lists and documents computer programs for comparative analysis; and summarizes current hardware development programs.

Wurm, J.

1990-01-01

161

CONJUGATE HEAT TRANSFER IN PLATE HEAT EXCHANGERS  

Microsoft Academic Search

In a real plate heat exchanger (PHX), heat transfer from the hot to the cold fluid is a conjugate problem, in which longitudinal heat conduction (LHC) along the walls plays some role. Large-scale LHC is always detrimental to the exchanger's effectiveness. On the contrary, if significant non-uniformities exist in the distribution of either convective heat transfer coefficient, small-scale LHC may

Michele Ciofalo

2004-01-01

162

1st and 2nd Law Characteristics in a Micropipe: Integrated Effects of Surface Roughness, Heat Flux and Reynolds Number  

Microsoft Academic Search

A computational study of the integrated effects of surface roughness, heat flux, and Reynolds number on the 1st and 2nd law characteristics of laminar-transitional flow in a micropipe is presented. Analyses are carried by solving the variable fluid property continuity, Navier–Stokes, and energy equations for the surface roughness, heat flux, and Reynolds number ranges of 1–50 ? m, 5–100 W\\/m,

A. Alper Ozalp

2009-01-01

163

Single-phase heat transfer and pressure drop characteristics of an integral-spine-fin within an annulus  

Microsoft Academic Search

The laminar, single phase heat transfer and friction characteristics of an integral-spine-fin pipe within an annulus are presented. The heat transfer coefficient was determined using a modified version of the Wilson Plot method. The test fluid was pumped through the annulus of a straight, 3 m test section. Three fluids were investigated: (1) tap water, (2) 34% ethylene glycol\\/water mixture,

M. A. Kedzierski; M. S. Kim

1994-01-01

164

Integrated modeling for the manufacture of Ni-based superalloy discs from solidification to final heat treatment  

Microsoft Academic Search

Process models of the various stages of gas-turbine disc manufacture have been integrated to simulate the physical and microstructural\\u000a transformations occurring within a nickel-based superalloy throughout the entire manufacturing route. Production of these\\u000a critical rotating structural components requires several distinct processing stages: vacuum-induction melting (VIM), vacuum-arc\\u000a remelting (VAR), homogenization heat treatment, cogging, forging, final heat treatment, and machining. During the

S. Tin; P. D. Lee; A. Kermanpur; M. McLean; M. Rist

2005-01-01

165

Enhancement of heat transfer in waste-heat heat exchangers  

SciTech Connect

The Fluidfire shallow fluidized bed heat transfer facility was modified during this program to give increased air flow capacity and to allow testing with different distributor plates and with two-stage heat exchangers. Tests were conducted using this heat transfer facility to investigate the effect of reduced distributor plate pressure loss and amount and type of bed material on the heat transfer performance of a single-stage fluidized bed heat exchanger. Elutriation from the bed was measured for different bed materials and distributor plates; alternate heat exchanger surfaces having different fin spacings were also tested. Two types of two-stage fluidized bed heat exchangers were tested: one having a baffle (having almost no pressure loss) located between the stages and which allowed bed material to recirculate between upper and lower beds; the second having two distributor plates in series with no recirculation of the bed material. The results obtained in the experimental program were used in conceptual design studies of multi-stage fluidized bed heat exchangers for waste heat recovery from diesel engine exhaust gases. Information was obtained from the literature and from diesel engine manufacturers to determine allowable diesel engine operating back pressures. The costs were estimated for two- and three-stage designs and were compared with costs obtained previously for single-stage fluidized bed and conventional heat exchanger designs.

Not Available

1980-07-01

166

Heat Island Effect  

MedlinePLUS

... to learn more. More Information on Urban Heat Islands Heat Island Basics Chapter from EPA’s Reducing Urban ... Island Video Segments What Is an Urban Heat Island? As urban areas develop, changes occur in their ...

167

Interconnecting District Heating Networks.  

National Technical Information Service (NTIS)

The National Energy Administration has, on behalf of the Swedish Government, investigated the potential for interconnecting district heating networks in Sweden. The purpose is twofold: by creating a large heat load, cheap energy sources like waste heat ca...

1985-01-01

168

INTEGRATED LASER SYSTEM FOR HEAT TREATMENT WITH HIGH POWER DIODE LASER  

Microsoft Academic Search

Due to the innovation in the field of high power diode lasers applications during the last years, heat treatment by using diode lasers has become very successful. However, at time this technology is most commonly used for simple two-dimensional geometries. An important industrial sector is the heat treatment of tools for sheet metal forming. At present conventional hardening processes are

J. Hannweber; S. Bonss; B. Brenner; E. Beyer

169

Model calculations on a flat-plate solar heat collector with integrated solar cells  

Microsoft Academic Search

A detailed physical model of a hybrid photovoltaic\\/thermal system is proposed, and algorithms for making quantitative predictions regarding the performance of the system are presented. The motivation for the present work is that solar cells act as good heat collectors and are fairly good selective absorbers. Additionally, most solar cells increase their efficiency when heat is drawn from the cells.

Trond Bergene; Ole Martin Løvvik

1995-01-01

170

Heat Generation, Temperature, and Thermal Stress of Structurally Integrated Piezo-Actuators  

Microsoft Academic Search

While converting electrical energy into mechanical energy to actuate structures, piezoelectric (PZT) elements experience a temperature increase due to internal heat generation caused by their mechanical damping and dielectric loss. In practice, if the actuation is operated at system resonance or with a relatively high electrical field, the heat generation throughout PZT actuators may be significant. The temperature rise of

Su-Wei Zhou; Craig A. Rogers

1995-01-01

171

Integration of constructal distributors to a mini crossflow heat exchanger and their assembly configuration optimization  

Microsoft Academic Search

In this paper, the idea of coupling constructal distributors\\/collectors with a mini crossflow heat exchanger (MCHE) to solve the problem of flow maldistribution is presented. After a brief description of the design and scaling laws of the constructal distributor, experimental and simulation results have been discussed to investigate relations among flow distribution, heat transfer and pressure drop. It is shown

Lingai Luo; Yilin Fan; Weiwei Zhang; Xigang Yuan; Noël Midoux

2007-01-01

172

Development of a time temperature integrator for quantification of thermal treatment in scraped surface heat exchangers  

Microsoft Academic Search

When processing highly viscous fluids in scraped surface heat exchangers, it is often difficult to follow the real heat flux received by each part of the product. Only average temperatures are measured, and the process cannot always guarantee a correct thermal treatment. During a pasteurisation process, the average temperature is around 80 °C, but some parts of the product may not

Jérôme Mabit; Rachida Belhamri; Francine Fayolle; Jack Legrand

2008-01-01

173

Regenerative adsorbent heat pump  

NASA Technical Reports Server (NTRS)

A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

Jones, Jack A. (Inventor)

1991-01-01

174

Rotary magnetic heat pump  

SciTech Connect

Magnetic heat pumps use the magneto-caloric effect to produce entropy changes necessary for heat pumping. A rotary magnetic heat pump has been analyzed and computer models have been developed. The contribution of viscous heat to the regenerator heat balance has been found to significantly restrict performance. The contribution of viscous heating is at least as important as the temperature differences required for regenerator heat transfer. Multiple magnet coils on a single rotor reduce the viscous work per field change cycle and result in greatly improved performance. Operation at 80% of Carnot efficiency with a heat pumping rate of 10 kW per kilogram of magnetic material is predicted.

Kirol, L.D.; Mills, J.I.

1984-01-01

175

Active heat pipe solar water heating system  

SciTech Connect

An ''active heat pipe'' solar water heating system is described. In its primary mode it transfers solar radiation energy from a high temperature solar evaporator to a low temperature water storage tank. For this mode to work properly, refrigerant must be circulated by a variable speed pump/compressor. It is expected that this system will offer better efficiency than conventional solar water systems and heat pump water heaters. This paper summarizes the benefits of active refrigeration cycle control and presents some simulation results comparing active heat pipe solar water heating systems to conventional systems.

Yoshino, H.; Kasayi, H.; Otsuka, N.; Thompson, P.

1983-08-01

176

Surface heating greenhouses with waste heat  

SciTech Connect

Surface heating of greenhouses is described as being accomplished by applying waste heated water on the outside of the greenhouse at the ridge and allowing this water to flow in a thin layer over the roof and sidewall surfaces. The water is then collected in gutters and returned to its source. The main advantages of this heating system over others for heating greenhouses with waste heat are its low capital costs and the fact that it can utilize wastes at quite low temperatures. 3 refs.

Walker, P.N.; Rand, H.J.

1980-01-01

177

Anisotropic heat transport in integrable and chaotic 3-D magnetic fields  

SciTech Connect

A study of anisotropic heat transport in 3-D chaotic magnetic fields is presented. The approach is based on the recently proposed Lagrangian-Green s function (LG) method in Ref. [1] that allows an efficient and accurate integration of the parallel transport equation applicable to general magnetic fields with local or non-local parallel flux closures. We focus on reversed shear magnetic field configurations known to exhibit separatrix reconnection and shearless transport barriers. The role of reconnection and magnetic field line chaos on temperature transport is studied. Numerical results are presented on the anomalous relaxation of radial temperature gradients in the presence of shearless Cantori partial barri- ers. Also, numerical evidence of non-local effective radial temperature transport in chaotic fields is presented. Going beyond purely parallel transport, the LG method is generalized to include finite perpendicular diffusivity, and the problem of temperature flattening inside a magnetic island is studied.

Del-Castillo-Negrete, Diego B [ORNL; Blazevski, D. [University of Texas, Austin; Chacon, Luis [ORNL

2012-01-01

178

A projected iterative method based on integral equations for inverse heat conduction in domains with a cut  

NASA Astrophysics Data System (ADS)

The Cauchy problem for the parabolic heat equation, consisting of the reconstruction of the solution from knowledge of the temperature and heat flux on a part of the boundary of the solution domain, is investigated in a planar region containing a cut. This linear inverse ill-posed problem is numerically solved using an iterative regularization procedure, where at each iteration step mixed Dirichlet-Neumann problems for the parabolic heat equation are used. Using the method of Rothe these mixed problems are reduced to a sequence of boundary integral equations. The integral equations have a square root singularity in the densities and logarithmic and hypersingularities in the kernels. Moreover, the mixed parabolic problems have singularities near the endpoints of the cut. Special techniques are employed to handle each of these (four) types of singularities, and analysis is performed in weighted spaces of square integrable functions. Numerical examples are included showing that the proposed regularizing procedure gives stable and accurate approximations.

Chapko, Roman; Tomas Johansson, B.; Vavrychuk, Vasyl

2013-06-01

179

Thermostructural applications of heat pipes  

NASA Technical Reports Server (NTRS)

The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight.

Peeples, M. E.; Reeder, J. C.; Sontag, K. E.

1979-01-01

180

Effects of supplemental zinc amino acid complex on gut integrity in heat-stressed growing pigs.  

PubMed

Heat stress (HS) jeopardizes livestock health and productivity and both may in part be mediated by reduced intestinal integrity. Dietary zinc improves a variety of bowel diseases, which are characterized by increased intestinal permeability. Study objectives were to evaluate the effects of supplemental zinc amino acid complex (ZnAA) on intestinal integrity in heat-stressed growing pigs. Crossbred gilts (43±6 kg BW) were ad libitum fed one of three diets: (1) control (ZnC; 120 ppm Zn as ZnSO4; n=13), (2) control+100 ppm Zn as ZnAA (Zn220; containing a total of 220 ppm Zn; n=14), and (3) control+200 ppm Zn as ZnAA (Zn320; containing a total of 320 ppm Zn; n=16). After 25 days on their respective diets, all pigs were exposed to constant HS conditions (36°C, ?50% humidity) for either 1 or 7 days. At the end of the environmental exposure, pigs were euthanized and blood and intestinal tissues were harvested immediately after sacrifice. As expected, HS increased rectal temperature (P?0.01; 40.23°C v. 38.93°C) and respiratory rate (P?0.01; 113 v. 36 bpm). Pigs receiving ZnAA tended to have increased rectal temperature (P=0.07; +0.27°C) compared with ZnC-fed pigs. HS markedly reduced feed intake (FI; P?0.01; 59%) and caused BW loss (2.10 kg), but neither variable was affected by dietary treatment. Fresh intestinal segments were assessed ex vivo for intestinal integrity. As HS progressed from days 1 to 7, both ileal and colonic transepithelial electrical resistance (TER) decreased (P?0.05; 34% and 22%, respectively). This was mirrored by an increase in ileal and colonic permeability to the macromolecule dextran (P?0.01; 13- and 56-fold, respectively), and increased colonic lipopolysaccharide permeability (P?0.05; threefold) with time. There was a quadratic response (P?0.05) to increasing ZnAA on ileal TER, as it was improved (P?0.05; 56%) in Zn220-fed pigs compared with ZnC. This study demonstrates that HS progressively compromises the intestinal barrier and supplementing ZnAA at the appropriate dose can improve aspects of small intestinal integrity during severe HS. PMID:24229744

Sanz Fernandez, M V; Pearce, S C; Gabler, N K; Patience, J F; Wilson, M E; Socha, M T; Torrison, J L; Rhoads, R P; Baumgard, L H

2014-01-01

181

Fluid-to-fluid spot-to-spreader (F2\\/S2) hybrid heat sink for integrated chip-level and hotspot-level thermal management  

Microsoft Academic Search

An innovative heat sink design aimed at meeting both the hotspot and large background heat flux requirements of next generation integrated circuits is presented. The heat sink design utilizes two separate, unmixed fluids to meet the cooling requirements of the chip with one fluid acting as a fluidic spreader dedicated to cooling the hotspots only, while the second fluid serves

Craig Green; Andrei G. Fedorov; Yogendra K. Joshi

2008-01-01

182

Loop heat pipes  

Microsoft Academic Search

Loop heat pipes (LHPs) are two-phase heat-transfer devices with capillary pumping of a working fluid. They possess all the main advantages of conventional heat pipes, but owing to the original design and special properties of the capillary structure are capable of transferring heat efficiency for distances up to several meters at any orientation in the gravity field, or to several

Yu. F. Maydanik

2005-01-01

183

REACH. Heating Units.  

ERIC Educational Resources Information Center

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized units in the area of heating. The instructional units focus on electric heating systems, gas heating systems, and oil burning systems. Each unit follows a typical format that includes a unit…

Stanfield, Carter; And Others

184

Nature's Heat Exchangers.  

ERIC Educational Resources Information Center

Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

Barnes, George

1991-01-01

185

Rotary magnetic heat pump  

DOEpatents

A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

Kirol, Lance D. (Shelly, ID)

1988-01-01

186

Hot water heating system  

Microsoft Academic Search

A solar hot water heating system has a primary tank heated by solar energy utilizing a heat transfer medium circulated between a solar collector and a heat exchanger located in the primary tank. Usually a back-up tank is provided to supplement the solar system. The primary tank receives cold water from a pressurized source. Its hot water outlet is connected

1984-01-01

187

Infrared Radiant Heating.  

National Technical Information Service (NTIS)

Retrofitting convective forced air heating systems with infrared (IR) systems can save as much as 50 percent of the total heating bill. Infrared heating is more efficient for two reasons: it can be directed to heat only occupied space; and it does not hea...

S. Cannon M. Rocha

1996-01-01

188

Rotary magnetic heat pump  

DOEpatents

A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

Kirol, L.D.

1987-02-11

189

Engineering heat transfer  

Microsoft Academic Search

The basic concepts of heat transfer are set forth, and the fundamentals of numerical analysis appropriate to solving heat transfer problems are covered. In some example problems, numerical solutions, flow charts, example FORTRAN programs, and computer output are given. Conduction, convection, thermal radiation, and combined mechanisms of heat transfer are investigated. A chapter on heat transfer equipment is given, and

J. R. Welty

1974-01-01

190

Thulium-170 heat source  

DOEpatents

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

Walter, Carl E. (Pleasanton, CA); Van Konynenburg, Richard (Livermore, CA); VanSant, James H. (Tracy, CA)

1992-01-01

191

Heat Treating Apparatus  

DOEpatents

Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

De Saro, Robert (Annandale, NJ); Bateman, Willis (Sutton Colfield, GB)

2002-09-10

192

Thermoelectric heat exchange element  

DOEpatents

A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

Callas, James J. (Peoria, IL); Taher, Mahmoud A. (Peoria, IL)

2007-08-14

193

Integrated modelling of steady-state scenarios and heating and current drive mixes for ITER  

SciTech Connect

Recent progress on ITER steady-state (SS) scenario modelling by the ITPA-IOS group is reviewed. Code-to-code benchmarks as the IOS group's common activities for the two SS scenarios (weak shear scenario and internal transport barrier scenario) are discussed in terms of transport, kinetic profiles, and heating and current drive (CD) sources using various transport codes. Weak magnetic shear scenarios integrate the plasma core and edge by combining a theory-based transport model (GLF23) with scaled experimental boundary profiles. The edge profiles (at normalized radius rho = 0.8-1.0) are adopted from an edge-localized mode-averaged analysis of a DIII-D ITER demonstration discharge. A fully noninductive SS scenario is achieved with fusion gain Q = 4.3, noninductive fraction f(NI) = 100%, bootstrap current fraction f(BS) = 63% and normalized beta beta(N) = 2.7 at plasma current I(p) = 8MA and toroidal field B(T) = 5.3 T using ITER day-1 heating and CD capability. Substantial uncertainties come from outside the radius of setting the boundary conditions (rho = 0.8). The present simulation assumed that beta(N)(rho) at the top of the pedestal (rho = 0.91) is about 25% above the peeling-ballooning threshold. ITER will have a challenge to achieve the boundary, considering different operating conditions (T(e)/T(i) approximate to 1 and density peaking). Overall, the experimentally scaled edge is an optimistic side of the prediction. A number of SS scenarios with different heating and CD mixes in a wide range of conditions were explored by exploiting the weak-shear steady-state solution procedure with the GLF23 transport model and the scaled experimental edge. The results are also presented in the operation space for DT neutron power versus stationary burn pulse duration with assumed poloidal flux availability at the beginning of stationary burn, indicating that the long pulse operation goal (3000s) at I(p) = 9 MA is possible. Source calculations in these simulations have been revised for electron cyclotron current drive including parallel momentum conservation effects and for neutral beam current drive with finite orbit and magnetic pitch effects.

Murakami, Masanori [ORNL; Park, Jin Myung [ORNL; Giruzzi, G. [CEA, IRFM, France; Garcia, J. [CEA Cadarache, St. Paul lex Durance, France; Bonoli, P. T. [Massachusetts Institute of Technology (MIT); Budny, R. V. [Princeton Plasma Physics Laboratory (PPPL); Doyle, E. J. [University of California, Los Angeles; Fukuyama, A. [Kyoto University, Japan; Ferron, J.R. [General Atomics, San Diego; Hayashi, N. [Japan Atomic Energy Agency (JAEA), Naka; Honda, M. [Japan Atomic Energy Agency (JAEA), Naka; Hubbard, A. [MIT Plasma Science & Fusion Center, Cambridge, MA 02139 USA; Hong, R. M. [General Atomics, San Diego; Ide, S. [Japan Atomic Energy Agency (JAEA), Naka; Imbeaux, F. [CEA Cadarache, St. Paul lex Durance, France; Jaeger, Erwin Frederick [ORNL; Jernigan, Thomas C [ORNL; Luce, T.C. [General Atomics, San Diego; Na, Y S [Seoul National University of Technology, Korea; Oikawa, T. [ITER Organization, Saint Paul Lez Durance, France; Osborne, T.H. [General Atomics, San Diego; Parail, V. [Association EURATOM-CCFE, Abingdon, UK; Polevoi, A. [ITER Organization, Saint Paul Lez Durance, France; Prater, R. [General Atomics; Sips, A C C [Max Planck Institute for Plasma Physics, Garching, Germany; Shafer, M. W. [University of Wisconsin, Madison; Snipes, J. A. [ITER Organization, Cadarache, France; St. John, H. E. [ITER Organization, Saint Paul Lez Durance, France; Snyder, P. B. [General Atomics, San Diego; Voitsekhovitch, I [UKAEA Fusion, Culham UK

2011-01-01

194

Integrated modelling of steady-state scenarios and heating and current drive mixes for ITER  

NASA Astrophysics Data System (ADS)

Recent progress on ITER steady-state (SS) scenario modelling by the ITPA-IOS group is reviewed. Code-to-code benchmarks as the IOS group's common activities for the two SS scenarios (weak shear scenario and internal transport barrier scenario) are discussed in terms of transport, kinetic profiles, and heating and current drive (CD) sources using various transport codes. Weak magnetic shear scenarios integrate the plasma core and edge by combining a theory-based transport model (GLF23) with scaled experimental boundary profiles. The edge profiles (at normalized radius ? = 0.8-1.0) are adopted from an edge-localized mode-averaged analysis of a DIII-D ITER demonstration discharge. A fully noninductive SS scenario is achieved with fusion gain Q = 4.3, noninductive fraction fNI = 100%, bootstrap current fraction fBS = 63% and normalized beta ?N = 2.7 at plasma current Ip = 8 MA and toroidal field BT = 5.3 T using ITER day-1 heating and CD capability. Substantial uncertainties come from outside the radius of setting the boundary conditions (? = 0.8). The present simulation assumed that ?N (?) at the top of the pedestal (? = 0.91) is about 25% above the peeling-ballooning threshold. ITER will have a challenge to achieve the boundary, considering different operating conditions (Te/Ti ? 1 and density peaking). Overall, the experimentally scaled edge is an optimistic side of the prediction. A number of SS scenarios with different heating and CD mixes in a wide range of conditions were explored by exploiting the weak-shear steady-state solution procedure with the GLF23 transport model and the scaled experimental edge. The results are also presented in the operation space for DT neutron power versus stationary burn pulse duration with assumed poloidal flux availability at the beginning of stationary burn, indicating that the long pulse operation goal (3000 s) at Ip = 9 MA is possible. Source calculations in these simulations have been revised for electron cyclotron current drive including parallel momentum conservation effects and for neutral beam current drive with finite orbit and magnetic pitch effects.

Murakami, M.; Park, J. M.; Giruzzi, G.; Garcia, J.; Bonoli, P.; Budny, R. V.; Doyle, E. J.; Fukuyama, A.; Hayashi, N.; Honda, M.; Hubbard, A.; Ide, S.; Imbeaux, F.; Jaeger, E. F.; Luce, T. C.; Na, Y.-S.; Oikawa, T.; Osborne, T. H.; Parail, V.; Polevoi, A.; Prater, R.; Sips, A. C. C.; Snipes, J.; St. John, H. E.; Snyder, P. B.; Voitsekhovitch, I.; ITPA/Integrated Operation Scenario Group

2011-10-01

195

Dual effect of heat shock on DNA replication and genome integrity.  

PubMed

Heat shock (HS) is one of the better-studied exogenous stress factors. However, little is known about its effects on DNA integrity and the DNA replication process. In this study, we show that in G1 and G2 cells, HS induces a countable number of double-stranded breaks (DSBs) in the DNA that are marked by ?H2AX. In contrast, in S-phase cells, HS does not induce DSBs but instead causes an arrest or deceleration of the progression of the replication forks in a temperature-dependent manner. This response also provoked phosphorylation of H2AX, which appeared at the sites of replication. Moreover, the phosphorylation of H2AX at or close to the replication fork rescued the fork from total collapse. Collectively our data suggest that in an asynchronous cell culture, HS might affect DNA integrity both directly and via arrest of replication fork progression and that the phosphorylation of H2AX has a protective effect on the arrested replication forks in addition to its known DNA damage signaling function. PMID:22787276

Velichko, Artem K; Petrova, Nadezhda V; Kantidze, Omar L; Razin, Sergey V

2012-09-01

196

Dual effect of heat shock on DNA replication and genome integrity  

PubMed Central

Heat shock (HS) is one of the better-studied exogenous stress factors. However, little is known about its effects on DNA integrity and the DNA replication process. In this study, we show that in G1 and G2 cells, HS induces a countable number of double-stranded breaks (DSBs) in the DNA that are marked by ?H2AX. In contrast, in S-phase cells, HS does not induce DSBs but instead causes an arrest or deceleration of the progression of the replication forks in a temperature-dependent manner. This response also provoked phosphorylation of H2AX, which appeared at the sites of replication. Moreover, the phosphorylation of H2AX at or close to the replication fork rescued the fork from total collapse. Collectively our data suggest that in an asynchronous cell culture, HS might affect DNA integrity both directly and via arrest of replication fork progression and that the phosphorylation of H2AX has a protective effect on the arrested replication forks in addition to its known DNA damage signaling function.

Velichko, Artem K.; Petrova, Nadezhda V.; Kantidze, Omar L.; Razin, Sergey V.

2012-01-01

197

Heat cascading regenerative sorption heat pump  

NASA Technical Reports Server (NTRS)

A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

Jones, Jack A. (Inventor)

1995-01-01

198

Increase of COP for heat transformer in water purification systems. Part I – Increasing heat source temperature  

Microsoft Academic Search

The integration of a water purification system in a heat transformer allows a fraction of heat obtained by the heat transformer to be recycled, increasing the heat source temperature. Consequently, the evaporator and generator temperatures are also increased. For any operating conditions, keeping the condenser and absorber temperatures and also the heat load to the evaporator and generator, a higher

J. Siqueiros; R. J. Romero

2007-01-01

199

Scroll heat sink: A novel heat sink with the moving fins inserted between the cooling fins  

Microsoft Academic Search

In this paper, a new type of a fan-integrated heat sink named a scroll heat sink is proposed and demonstrated. The most striking feature of the scroll heat sink is that heat dissipation and fluid pumping occurs simultaneously in the whole cooling space without requiring any additional space for a fan module. In the scroll heat sink, the moving fins,

Tae Young Kim; Dong-Kwon Kim; Sung Jin Kim

2008-01-01

200

COP prediction for the integration of a water purification process in a heat transformer: with and without energy recycling  

Microsoft Academic Search

A predictive model for a water purification process integrated in an absorption heat transformer, using an artificial neural network, is proposed in order to obtain on-line predictions of the coefficient of performance (COP). This model takes into account the input and output temperatures for each one of the four components (absorber, generator, evaporator, and condenser), as well as two pressure

J. A. Hernández; D. Juárez-Romero; L. I. Morales; J. Siqueiros

2008-01-01

201

Heat collection system  

SciTech Connect

A heat collection system is disclosed which is capable of collecting heat from an animal husbandry enclosures such as a dairy barn, and transferring the heat into a home. Animal husbandry enclosures, such as dairy barns, tend to have excess heat, even in winter, the excess heat normally being wasted. The heat is collected by a pair of evaporators located in the dairy barn, with the evaporators being oversized to limit the amount of cooling taking place in the barn. Fluid from the evaporators is compressed by compressors after which it passes through a condenser from which heat may be extracted into the home. Pressure regulating valves are provided to insure that the compressors are not overloaded and to insure that a maximum heating effect is achieved. A thermostatically controlled fan is provided to drive air across the condenser so that heat is introduced into the home.

Ramlow, B.L.; Steele, R.R.

1982-04-06

202

Infrared radiant heating  

SciTech Connect

Retrofitting convective forced air heating systems with infrared (IR) systems can save as much as 50 percent of the total heating bill. Infrared heating is more efficient for two reasons: it can be directed to heat only occupied space; and it does not heat the air in a space, it only heats people and objects. Infrared heating works best where convective heaters are not practical. Large open bay buildings, such as hangars, workshops, and warehouses, with large volumes of air to be heated and plenty of unoccupied space are good candidates for retrofit. This TechData Sheet will help activity personnel understand infrared radiant heating, and identify opportunities for energy-conserving retrofit projects.

Cannon, S.; Rocha, M.

1996-05-01

203

Heat Pipe Technology  

NASA Technical Reports Server (NTRS)

The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

1981-01-01

204

Solar heating system  

SciTech Connect

A solar heating system including a flat plate solar collector having a heat absorber woven basket fashion across a riser grid system containing suitable flow medium for being heated by the solar radiation. A heat exchange column is coupled to the riser grid system for extracting the heat from the flow medium to provide it to heating, hot water, and the like. The heat exchange column includes a number of continuous coils placed within a tank and having a circulating loop pass a liquid from the bottom of the tank to the top of the tank where it will flow over all of the coils transferring heat from one coil to the other. The flow is controlled by means of the load demand and the available supply of heat. Excess heat is stored in a heat storage system having a plurality of blocks of Glauber salt containing matrix material through which pass pipes containing the heated liquid. One of the riser grid systems can be utilized as part of an absorption cycle air conditioning system by passing the heated fluid medium into a regenerator placed adjacent to the collector to effectively form a distillation process. In place of the liquid solar collector, an air heating solar collector is also provided.

Steinberg, A.

1984-02-07

205

Recover that low-level heat  

SciTech Connect

The author says direct heat integration is the best way to use heat that would otherwise be rejected. To recover low level heat, there are several possibilities that the author discusses in detail. They are: heat distribution systems, liquid runaround systems, organic Rankine cycles, and absorption refrigeration.

O'Brien, W.J.

1987-12-01

206

Exact triple integrals of beam functions. [in application of Galerkin method to heat and mass transfer problems  

NASA Technical Reports Server (NTRS)

Definite triple integrals encountered in applying the Galerkin method to the problem of heat and mass transfer across rectangular enclosures are discussed. Rather than evaluating them numerically, the technique described by Reid and Harris (1958) was extended to obtain the exact solution of the integrals. In the process, four linear simultaneous equations with triple integrals as unknowns were obtained. These equations were then solved exactly to obtain the closed form solution. Since closed form representations of this type have been shown to be useful in solving nonlinear hydrodynamic problems by series expansion, the integrals are presented here in general form.

Jhaveri, B. S.; Rosenberger, F.

1982-01-01

207

Experimental study of an integral catalytic combustor: Heat exchanger for Stirling engines  

NASA Technical Reports Server (NTRS)

The feasibility of using catalytic combustion with heat removal for the Stirling engine to reduce exhaust emissions and also improve heat transfer to the working fluid was studied using spaced parallel plates. An internally air-cooled heat exchanger was placed between two noble metal catalytic plates. A preheated fuel-air mixture passed between the plates and reacted on the surface of the catalyzed plates. Heat was removed from the catalytic surface by radiation and convection to the aircooled heat exchangers to control temperature and minimize thermal nitrogen oxide emissions. Test conditions were inlet combustion air temperatures from 850 to 900 K, inlet velocities of about 10 m/s, equivalence ratios from 0.5 to 0.9, and pressures from 1.3x10 to the 5th power to 2.0x10 to the 5th power Pa. Propane fuel was used for all testing. Combustion efficiencies greater than 99.5 percent were measured. Nitrogen oxide emissions ranged from 1.7 to 3.3 g NO2/kg fuel. The results demonstrate the feasibility of the concept and indicate that further investigation of the concept is warranted.

Bulzan, D. L.

1982-01-01

208

Heat pipes for industrial waste heat recovery  

Microsoft Academic Search

Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes are investigated. Economic studies of the use of

M. A. Merrigan

1981-01-01

209

Heat transfer system  

DOEpatents

A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

McGuire, Joseph C. (Richland, WA)

1982-01-01

210

Heat transfer system  

DOEpatents

A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

Not Available

1980-03-07

211

Microscale Regenerative Heat Exchanger  

NASA Technical Reports Server (NTRS)

The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

2006-01-01

212

Wound tube heat exchanger  

DOEpatents

What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

Ecker, Amir L. (Duncanville, TX)

1983-01-01

213

Composite heat pipe development status: Development of lightweight prototype carbon-carbon heat pipe with integral fins and metal foil liner  

NASA Technical Reports Server (NTRS)

This report discusses development and proof-of-concept testing of a new lightweight carbon-carbon (C-C) space radiator heat pipe, carried out under the NASA Civil Space Technology Initiative (CSTI) High Capacity Power Program. The prototype heat pipe, equipped with a niobium-zirconium foil liner, was filled with potassium working fluid and tested for 11 hours, including startup from ambient temperature with the working fluid initially in the frozen state to near 700 K condenser temperature. Steady-state heat pipe input power during testing was facility limited to about 300 watts. Post test inspection showed the heat pipe to be in excellent condition after eight thermal cycles from ambient to steady-state operating temperature. Utilization of other liner materials and working fluids would greatly extend the spectrum of service temperatures for this technology, with potential applications ranging from small spacecraft heat rejection to aircraft and terrestrial uses.

Juhasz, Albert J.; Rovang, Richard D.

1995-01-01

214

Precooling heat exchange arrangement integral with mounting structure fairing of gas turbine engine  

SciTech Connect

This patent describes a gas turbine engine including a core engine, a casing surrounding the core engine and defining an annular cooling compartment, and outer annular nacelle spaced radially outward from the casing and defining therebetween an annular fan duct, and an engine mounting structure extending radially between and interconnecting the nacelle and the casing, a precooling heat exchange arrangement. It comprises a hollow fairing mounted on a forward side of the mounting structure across the main air flow through the fan duct, means for routing a source of high pressure hot bleed air to the fairing; at least one heat exchanger mounted in the fairing and including a heat transfer structure having an interior connected in communication with the routing means; and an air flow control mechanism in communication with and mounted to the fairing.

Miller, F.E.

1992-06-23

215

Integration of Thermal Indoor Conditions into Operational Heat Health Warning Systems  

NASA Astrophysics Data System (ADS)

The 2003 heat wave in Western Europe with altogether 35,000 to 50,000 deaths in Europe, several thousands of which occurred in Germany, has clearly pointed out the danger arising from long periods with high heat load. As a consequence, Germany, as many other European countries, has started to implement a Heat Health Warning System (HHWS). The German HHWS is based on the ‘Perceived Temperature'. The 'Perceived Temperature' is determined through a heat budget model of the human organism which includes the main thermophysiologically relevant mechanisms of heat exchange with the atmosphere. The most important meteorological ambience parameters included in the model are air temperature, humidity, wind speed and radiation fluxes in the short-wave and long-wave ranges. In addition to using a heat budget model for the assessment of the thermal load, the German HHWS also takes into account that the human body reacts in different ways to its thermal environment due to physiological adaptation (short-term acclimatisation) and short-term behavioural adaptation. The restriction of such an approach, like the majority of approaches used to issue heat warnings, is that the threshold for a warning is generally derived from meteorological observations and that warnings are issued on the basis of weather forecasts. Both, the observed data and the weather forecasts are only available for outside conditions. The group of people who are most at risk of suffering from a heat wave, however, are the elderly and frail who mainly stay inside. The indoor situation, which varies largely from the conditions outside, is not taken into account by most of the warning systems. To overcome this limitation the DWD, in co-operation with the Fraunhofer Institute for Solar Energy Systems, has developed a model which simulates the thermal conditions in the indoor environment. As air-conditioning in private housing in Germany is not very common, the thermal indoor conditions depend on the outside conditions, on the building characteristics, and on the inhabitants' behaviour. The thermal building simulation model estimates the indoor heat load based of the predicted meteorological outside conditions by calculating the operative indoor temperature. The building types prevailing in Germany are quite heterogeneous. It was therefore decided to use for the thermal simulation a so-called "realistic worst-case” building type. In addition, a differentiation is made between two types of user behaviour: the active user opens the windows during the cold hours of the day and uses shading devices whereas the passive user does nothing to keep the heat outside. Since 2007, the DWD has been using the simulation of the indoor thermal conditions as an additional source of information for heat warnings. The information on the indoor conditions has proved very valuable for the decision whether to issue a heat warning or not.

Koppe, C.; Becker, P.; Pfafferott, J.

2009-09-01

216

Modeling the integration of thermoelectrics in anode exhaust combustors for waste heat recovery in fuel cell systems  

NASA Astrophysics Data System (ADS)

Recently developed small-scale hydrocarbon-fueled fuel cell systems for portable power under 1 kW have overall system efficiencies typically no higher than 30-35%. This study explores the possibility of using of thermoelectric waste heat recovery in anode exhaust combustors to improve the fuel cell system efficiencies by as much as 4-5% points and further to reduce required battery power during system start-up. Two models were used to explore this. The first model simulated an integrated SOFC system with a simplified catalytic combustor model with TEs integrated between the combustor and air preheating channels for waste heat recovery. This model provided the basis for assessing how much additional power can achieve during SOFC operation as a function of fuel cell operating conditions. Results for the SOFC system indicate that while the TEs may recover as much as 4% of the total fuel energy into the system, their benefit is reduced in part because they reduce the waste heat transferred back to the incoming air stream and thereby lower the SOFC operating temperatures and operating efficiencies. A second model transient model of a TE-integrated catalytic combustor explored the performance of the TEs during transient start-up of the combustor. This model incorporated more detailed catalytic combustion chemistry and enhanced cooling air fin heat transfer to show the dynamic heating of the integrated combustor. This detailed model provided a basis for exploring combustor designs and showed the importance of adequate reactant preheating when burning exhaust from a reformer during start-up for the TEs to produce significant power to reduce the size of system batteries for start-up.

Maghdouri Moghaddam, Anita

217

Heat Transfer Through Fabrics.  

National Technical Information Service (NTIS)

Heat is transferred through fabrics by convection, conduction and radiation and under certain circumstances by vaporization. Each mode is subject to different physical principles but the effect of the total heat absorbed by underlying skin is the same: if...

A. M. Stoll M. A. Chianta

1970-01-01

218

An electrohydrodynamic heat pipe  

NASA Technical Reports Server (NTRS)

Dielectric liquid for transfer of heat provides liquid flow from the condenser section to the evaporator section in conventional heat pipes. Working fluid is guided or pumped by an array of wire electrodes connected to a high-voltage source.

Jones, T. B.

1972-01-01

219

Heat Wave Safety Checklist  

MedlinePLUS

... heat has caused more deaths than all other weather events, including floods. A heat wave is a ... stroke include hot, red skin which may be dry or moist; changes in consciousness; vomiting; and high ...

220

Monogroove liquid heat exchanger  

NASA Technical Reports Server (NTRS)

A liquid supply control is disclosed for a heat transfer system which transports heat by liquid-vapor phase change of a working fluid. An assembly (10) of monogroove heat pipe legs (15) can be operated automatically as either heat acquisition devices or heat discharge sources. The liquid channels (27) of the heat pipe legs (15) are connected to a reservoir (35) which is filled and drained by respective filling and draining valves (30, 32). Information from liquid level sensors (50, 51) on the reservoir (35) is combined (60) with temperature information (55) from the liquid heat exchanger (12) and temperature information (56) from the assembly vapor conduit (42) to regulate filling and draining of the reservoir (35), so that the reservoir (35) in turn serves the liquid supply/drain needs of the heat pipe legs (15), on demand, by passive capillary action (20, 28).

Brown, Richard F. (Inventor); Edelstein, Fred (Inventor)

1990-01-01

221

Miniature Heat Pipes.  

National Technical Information Service (NTIS)

Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged 'heat pipes' for space application. To control the extreme temperature ranges in space, heat pipes are import...

1997-01-01

222

Compact, super heat exchanger  

NASA Technical Reports Server (NTRS)

Heat exchanger uses porous media to enhance heat transfer through walls of cooling channels, thereby lowering wall temperature. Porous media within cooling channel increases internal surface area from which heat can be transferred to coolant. Comparison data shows wall has lower temperature and coolant has higher temperature when porous medium is used within heat exchanger. Media can be sintered powedered metal, metal fibers, woven wire layers, or any porous metal having desired permeability and porosity.

Fortini, A.; Kazaroff, J. M.

1980-01-01

223

Urban Heat Islands  

NSDL National Science Digital Library

In this activity, students learn about the urban heat island effect by investigating which areas of their schoolyard have higher temperatures - trees, grass, asphalt, and other materials. Based on their results, they hypothesize how concentrations of surfaces that absorb heat might affect the temperature in cities - the urban heat island effect. Then they analyze data about the history of Los Angeles heat waves and look for patterns in the Los Angeles climate data and explore patterns.

Gardiner, Lisa; Universe, Windows T.

224

Isolated quantum heat engine.  

PubMed

We present a theoretical and numerical analysis of a quantum system that is capable of functioning as a heat engine. This system could be realized experimentally using cold bosonic atoms confined to a double well potential that is created by splitting a harmonic trap with a focused laser. The system shows thermalization, and can model a reversible heat engine cycle. This is the first demonstration of the operation of a heat engine with a finite quantum heat bath. PMID:22463540

Fialko, O; Hallwood, D W

2012-02-24

225

Abrasion resistant heat pipe  

DOEpatents

A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

Ernst, D.M.

1984-10-23

226

Methods of Heat Transfer  

NSDL National Science Digital Library

To help students better understand conduction, convection, and radiation as methods of heat transfer in solids, liquids and gases. Let's look at all three methods of heat transfer ... Overview of Conduction, Convection, Radiation Conduction- 1. Explain what happens as heat energy is supplied to one part of a solid. 2. Explain how energy is transferred by conduction through a solid. Convection- 1. What is ?anything fluid? ? Include two examples. 2. Describe how and why heat is transferred in ...

Carlone, Mrs.

2006-11-12

227

Solar heating system  

SciTech Connect

A subterranean furnace contains a shell in which a plurality of bricks are arranged in a mass. A mirror reflects sun light into the furnace chamber and onto a magnifying glass which concentrates the heat on the bricks. Air is circulated through the furnace chamber and is heated by the heat which is stored in the bricks. A gas burner is mounted beneath the mass of bricks to supply supplemental heat when needed.

Smith, J.

1982-07-20

228

Abrasion resistant heat pipe  

DOEpatents

A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

Ernst, Donald M. (Leola, PA)

1984-10-23

229

Heat pipes for industrial waste heat recovery  

NASA Astrophysics Data System (ADS)

Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes are investigated. Economic studies of the use of heat pipe based recuperators in industrial furnaces are conducted and payback periods determined as a function of material, fabrication, and installation cost.

Merrigan, M. A.

1981-01-01

230

Heat pipes for industrial waste heat recovery  

SciTech Connect

Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes have been investigated. Economic studies of the use of heat-pipe based recuperators in industrial furnaces have been conducted and payback periods determined as a function of material, fabrication, and installation cost.

Merrigan, M.A.

1981-01-01

231

Heat pump seasonal heating efficiency prediction  

SciTech Connect

This paper presents the results of a project to develop a simple and accurate predictive algorithm for heat pump heating efficiency. Field test data are gathered. Cycling losses are then predicted by means of a model. Laboratory tests were performed to evaluate the capacity and power transients during startup, and the effect of off cycle period on the startup transients. Frost-defrost tests were performed. Seasonal efficiency comparison for seven residences for field tests, steady state, cycling only, timed frost, and demand frost schemes are given. The performance predictions for the entire heating season are provided.

Miller, R.S.

1983-06-01

232

Integrated Heat Pipe-Thermal Storage Design for a Solar Receiver.  

National Technical Information Service (NTIS)

Light-weight heat pipe wall elements that incorporate a thermal storage subassembly within the vapor space are being developed as part of the Organic Rankine Cycle Solar Dynamic Power Systems (ORC-SDPS) receiver for the space station application. The oper...

E. S. Keddy J. T. Sena K. Woloshun M. A. Merrigan G. Heidenreich

1986-01-01

233

Integrated three-dimensional module heat exchanger for power electronics cooling  

DOEpatents

Embodiments discussed herein are directed to a power semiconductor packaging that removes heat from a semiconductor package through one or more cooling zones that are located in a laterally oriented position with respect to the semiconductor package. Additional embodiments are directed to circuit elements that are constructed from one or more modular power semiconductor packages.

Bennion, Kevin; Lustbader, Jason

2013-09-24

234

Integration of the transient heat-transfer equation for bodies moving in a fluid  

Microsoft Academic Search

In the present paper, the unsteady-state problem of convective heat transfer for bodies of arbitrary configuration moving in an ideal fluid (or for droplets moving in a viscous incompressible fluid) is analyzed in a thermal boundary layer approximation. A method, more general than Chao's (1969) method, is proposed for deriving the expression for the stream function.

Iu. P. Gupalo; A. D. Polianin; P. A. Priadkin; Iu. S. Riazantsev

1979-01-01

235

Serpentine heat exchanger  

Microsoft Academic Search

This patent describes a furnace having a burner means for providing hot products of combustion, and an air flow means for circulating conditioned air, a heat exchanger for transferring heat from products of combustion to conditioned air. The heat exchanger comprises first and second matched clamshell plates assembled together. The plates connected at their respective edges by a sealing means

1991-01-01

236

Heat Loss Calculation Exercise  

NSDL National Science Digital Library

This class exercise from Kirk Garrison is intended for construction students learning about home insulation and heating. The class will learn to calculate heat loss in a home by using an online home heat loss calculator. This exercise document includes student worksheets. This document may be downloaded in PDF file format.

Garrison, Kirk

2012-03-27

237

The heat pipe  

Microsoft Academic Search

The heat pipe is a device having a high thermal conductance which utilizes the transport of a vapour and rejection of latent heat to achieve efficient thermal energy transport. The theory of heat pipes is well developed. Their use in applications involving temperatures in the cryogenic regime, and with development units running as high as 2000 degrees C, shows that

P. D. Dunn; D. A. Reay

1973-01-01

238

Concerning Heat Defoliation.  

National Technical Information Service (NTIS)

The report contains observations on the 'heat defoliation' which sets in during extreme summer heat and simultaneous great dryness of the ground. The commonest form of heat defoliation is characterized by the fact that as a rule it is not the foliage situ...

J. Wiesner

1966-01-01

239

Solar heat regulator  

US Patent & Trademark Office Database

A solar heat regulating device selectively heats, with sunlight, the air in a building having a window therein and alternately shields and insulates the air in the building from the heat of sunlight. A frame is provided for mounting the solar heat regulating device inside the structure adjacent to the window. A plurality of hollow vanes each of which have a passageway therethrough. Each of the vanes has a heat absorptive surface on one side which allows solar radiation impinging thereon to heat the air in the passageways of the vanes. The vanes also have a heat reflective surface on another side. The heat reflective surface reflects the solar radiation impinging thereon and insulates the air inside the building from the heat of the sunlight. The vanes are rotatably mounted about vertical axes and spaced so that either the heat absorptive surfaces on the vanes or the heat reflective surfaces on the vanes may face the outside of the building. The device includes means for sealing the outside facing surfaces of the vanes from the inside of the building. Manifold means are also provided for conducting the cooler air from the inside of the building to the bottom of the passageways in the vanes and for conducting the heated air from the top of the passageways of the vanes to the inside of the building.

1987-04-07

240

Liquid heat capacity lasers  

DOEpatents

The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

2007-05-01

241

Heat of wood pyrolysis  

Microsoft Academic Search

The heat of pyrolysis of beech and spruce wood was investigated by means of a differential scanning calorimeter. Wide variations were found for the heat of the primary pyrolysis process, depending on the initial sample weight and on the conditions used in the measurements. However, reporting the heat of the primary pyrolysis process versus the final char yield resulted in

J. Rath; M. G. Wolfinger; G. Steiner; G. Krammer; F. Barontini; V. Cozzani

2003-01-01

242

Plasma heating in JET  

Microsoft Academic Search

Heating the JET plasma well above temperatures reached in the ohmic phase is the aim of the two additional heating systems planned for JET: ion cyclotron resonance heating (ICRF) and neutral beam injection (NBI). Operations with the latter started in February 1986, initially with hydrogen injection, up to a power level of 7 MW. ICRF power has been delivered to

A. Ainsworth; H. Altmann; R. J. Anderson; J. Arbez; D. Bartlett; W. Bailey; K. Behringer; E. Bertolini; P. Bertoldi; C. H. Best; V. Bhatnagar; R. J. Bickerton; G. Boissin; T. Bonicelli; S. Booth; A. Boschi; G. Bosia; M. Botman; H. Brelen; H. Brinkschulte; M. L. Browne; M. Brusati; T. Budd; M. Bures; P. Butcher; H. Buttgereit; D. Cacaut; C. Caldwell-Nichols; D. Campbell; J. Carwardine; G. Celentano; C. D. Challis; A. Cheetman; J. Christiansen; C. Christodoulopoulos; P. Chuilon; R. Claesen; J. P. Coad; M. Cooke; J. G. Cordey; W. Core; S. Corti; A. E. Costley; G. Cottrell; J. Dean; E. Deksnis; G. Deschamps; K. J. Dietz; J. Dobbing; S. E. Dorling; D. F. Duechs; G. Duesing; H. Duquenoy; L. de Kock; A. Edwards; W. Engelhardt; F. Erhorn; B. Eriksson; H. Falter; T. Hellsten; J. L. Hemmerich; R. Hemsworth; F. Hendriks; R. F. Herzog; L. Horton; J. How; M. Huart; A. Hubbard; M. Hugon; P. Jones; J. Kaeline; A. Kaellne; A. Kaye; B. E. Keen; M. Keilhacker; G. Kinahan; A. Konstantellos; P. Kupschus; P. Lallia; J. R. Last; N. Foden; C. Froger; K. Fullard; A. Galetsas; A. Gallacher; A. Gibson; R. D. Gill; A. Geode; A. Gondhalekar; N. A. Gottardi; C. Gowers; R. Granetz; B. Green; S. Gregoli; F. S. Griph; R. Haange; C. J. Hancock; P. Harbour; R. F. Herog; J. Kaellne; L. Lauro-Taroni; E. Lazzaro; R. C. Lobel; P. Lomas; M. Lorenzo-Gottardi; C. Lowry; G. Magyar; D. Maissonneir; M. Malacarne; V. Marchese; P. Massmann; P. McMullen; M. J. Mead; P. Meriguet; V. Merlo; S. Mills; P. Millward; A. Moissonnier; P. L. Mondini; P. Morgan; G. Murphy; M. F. Nave; L. Nickesson; P. Nielson; P. Noll; S. Nowak; W. Obert; B. Oliver; M. Olsson; J. O'Rourke; M. G. Pacco; J. Paillere; L. Pannacione; S. Papastergiou; D. Pasini; M. Pescatore; J. Planncoulaine; J. P. Poffe; R. Prentice; T. Raimondi; C. Raymond; P. H. Rebut; J. Removille; W. Riediker; R. Roberts; A. Rolfe; R. T. Ross; G. Sadler; J. Saffert; N. Salmon; A. Sand; A. Santagiustina; R. Saunders; M. Schmid; F. C. Schueller; K. Selin; R. Shaw; D. Sigournay; R. Simonini; P. Smeulders; L. Sonnerup; K. Sonnenberg; M. Stamp; C. A. Steed; D. Stork; P. E. Stott; T. E. Stringer; D. Summers; A. Tanga; A. Taroni; A. Terrington; A. Tesini; P. R. Thomas; E. Thompson; F. Tibone; R. Tivery; E. Usselmann; H. Van der Beken; M. Von Hellerman; J. E. Van Montfoort; T. Wade; C. Walker; B. A. Wallander; M. Walravens; K. Walter; M. L. Watkins; M. Watson; D. Webberley; J. Wesson; J. Wilks; T. Winkel; C. Woodward; M. Wykes; D. Young; L. Zennelili; J. Zwart; B. Beaumont; D. Gambier; D. Moreau; J. Ehrenberg; H. Jaeckel; S. Kissel; U. Kuephnapfel; R. Mueller; A. Staebler; A. Weller; J. H. Hamnen; M. Evrared; M. Gadeberg; K. Thomsen; P. Dupperrex; G. Tonetti; N. Lopez-Cardozo; B. Tubbing; J. Von Seggern; J. Tagle; F. Bombarda; G. Bracco; R. Giannella; R. Carolan; M. Cox; M. Forrest; D. Goodall; N. Hawkes; P. Haynes; J. Hugill; K. D. Lawson; G. McCracken; J. Partridge; N. Peacock; J. Snipes; T. Todd; H. Schamel; H. Summers; S. Tsuji; G. Tallents

1986-01-01

243

Champagne Heat Pump  

NASA Technical Reports Server (NTRS)

The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

Jones, Jack A.

2004-01-01

244

An isotope heat source integrated with a 7 kW/e/ to 25 kW/e/ Brayton cycle space power supply.  

NASA Technical Reports Server (NTRS)

The power system described is intended for applications in a manned space mission. The Isotope Reentry Vehicle (IRV) developed is considered together with the Heat Source (HS), the Heat Source Heat Exchanger and the Brayton Cycle Power Conversion Module. Other subjects discussed include the IRV/Brayton cycle spacecraft integration concept, abort and deorbit mechanization, emergency cooling methods, and crew shielding requirements. Mounting and integration for the IRV is to a large degree controlled by nuclear safety requirements. Another major factor in the installation concept is the type of emergency cooling or passive heat dump mode used in rejection of HS energy.

Ryan, R. L.; Graham, J. W.; Coombs, M. G.; Bloomfield, H. S.

1972-01-01

245

Chemical heat pump  

DOEpatents

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

Greiner, Leonard (2750-C Segerstrom Ave., Santa Ana, CA 92704)

1980-01-01

246

Heat Rash or Prickly Heat (Miliaria Rubra)  

MedlinePLUS

... Symptoms of heat stroke include a very high temperature, of 105°F or greater, decreased or loss ... treated by trying to quickly reduce the core temperature to normal. Immersion, evaporative, or invasive cooling techniques ...

247

Applied heat transfer  

SciTech Connect

Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

Ganapathy, V.

1982-01-01

248

Heat pipe investigations  

NASA Technical Reports Server (NTRS)

The OAO-C spacecraft has three circular heat pipes, each of a different internal design, located in the space between the spacecraft structural tube and the experiment tube, which are designed to isothermalize the structure. Two of the pipes are used to transport high heat loads, and the third is for low heat loads. The test problems deal with the charging of the pipes, modifications, the mobile tilt table, the position indicator, and the heat input mechanisms. The final results showed that the techniques used were adequate for thermal-vacuum testing of heat pipes.

Marshburn, J. P.

1972-01-01

249

Heat recovery casebook  

SciTech Connect

Plants and factories could apply a great variety of sources and uses for valuable waste heat. Applications may be evaluated on the basis of real use for a specific waste heat, high-enough temperature and quality of work, and feasibility of mechanical heat transfer method. Classification may be by temperature, application, heat-transfer equipment, etc. Many buildings and industrial processes lend themselves well to heat-recovery strategies. Five case histories describe successful systems used by the Continental Corporation Data Center; Nabisco, Inc.; Kasper Foundry Company; Seven Up Bottling Company of Indiana; and Lehr Precision Tool company. (DCK)

Lawn, J.

1980-10-01

250

Urban heat island  

NASA Technical Reports Server (NTRS)

The phenomenon of urban heat island was investigated by the use of LANDSAT Thematic Mapper data sets collected over the metropolitan area of Washington DC (U.S.). By combining the retrieved spectral albedos and temperatures, urban modification on radiation budgets of five surface categories were analyzed. The surface radiation budget imagery of the area show that urban heating is attributable to a large heat flux from the rapidly heating surfaces of asphalt, bare soil and short grass. In summer, symptoms of diurnal heating begin to appear by mid morning and can be about 10 degrees warmer than nearby woodlands in summer.

Kim, Hongsuk H.

1991-01-01

251

Heating and cooling  

NSDL National Science Digital Library

Heating and cooling homes and businesses require a major energy commitment. This informational piece, part of a series about the future of energy, introduces students to the energy needed to heat and cool homes and workplaces. Students explore energy requirements in the home and at work and discuss current technologies to improve heating and cooling efficiencies. Articles on heat pumps and solar heating and cooling techniques are accessible from a sidebar. A link to a PBS NewsHour article on air conditioning efficiency and a link to material discussing alternatives to air conditioning are also provided. Copyright 2005 Eisenhower National Clearinghouse

Project, Iowa P.

2004-01-01

252

Absorption heat pump system  

DOEpatents

An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

1984-01-01

253

Flexible heating head for induction heating  

NASA Technical Reports Server (NTRS)

An induction heating head includes a length of wire having first and second opposite ends and being wound in a flat spiral shape to form an induction coil, a capacitor connected to the first and second ends of the wire, the induction coil and capacitor defining a tank circuit, and a flexible, elastomeric body molded to encase the induction coil. When a susceptor is placed in juxtaposition to the body, and the tank circuit is powered, the susceptor is inductively heated.

Fox, Robert L. (inventor); Johnson, Samuel D. (inventor); Coultrip, Robert H. (inventor); Phillips, W. Morris (inventor)

1993-01-01

254

Stand-alone photovoltaic (PV) integrated with earth to air heat exchanger (EAHE) for space heating\\/cooling of adobe house in New Delhi (India)  

Microsoft Academic Search

This paper deals with an experimental outdoor annual performance evaluation of 2.32kWP photovoltaic (PV) power system located at solar energy park in New Delhi composite climatic conditions. This PV system operates the daily electrical load nearly 10kWh\\/day which comprises of various applications such as electric air blower of an earth to air heat exchanger (EAHE) used for heating\\/cooling of adobe

Arvind Chel; G. N. Tiwari

2010-01-01

255

Ceramic heat recuperators for industrial heat recovery  

SciTech Connect

Results are presented from a continuing program whose purpose is to demonstrate the technical and economic feasibility of using ceramic heat recuperators for industrial heat recovery. The information presented can be used by engineers in industry to evaluate their specific furnace applications and to estimate the technical requirements and economic benefits from the use of ceramic heat recuperators. Chapter 2 presents methods that can be used to estimate the amount of energy savings by recuperation. Chapter 3 gives a brief background in heat exchanger design theory so that the reader can understand the procedures involved in designing and sizing heat exchangers for a given application. The specific GTE core design and the recuperator fabrication, housing and installation are discussed in Chapter 4. The demonstration project results are presented in Chapter 5. Each demonstration is described and the results, economics and problem areas discussed. The Appendices provide details that will allow the engineer in industry to select a core, size a heat exchanger, calculate the performance, determine energy saved and estimate the economics of using a ceramic recuperator for a specific industrial application. (LCL)

Not Available

1980-05-01

256

Heat pump apparatus  

DOEpatents

A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

Nelson, Paul A. (Wheaton, IL); Horowitz, Jeffrey S. (Woodridge, IL)

1983-01-01

257

The thermal performance of heat pipes with localized heat input  

NASA Technical Reports Server (NTRS)

The performance of heat pipes with localized heat input including the effects of axial and circumferential heat conduction under high and low working temperatures is investigated. The numerical results show that when heat pipes are spot heated, the peak temperature of the wall is greatly reduced and the surface can be protected from being burned out by the high heat flux. The boiling limitation becomes the most important limitation for this type of heat pipe. Numerical results for block heating a heat pipe with low working temperatures indicate a good agreement with existing experimental data. It is also shown that most of the input heat passes through the wall beneath the heated block.

Cao, Yiding; Faghri, Amir; Mahefkey, E. T.

1989-01-01

258

Heat tube device  

NASA Technical Reports Server (NTRS)

The present invention discloses a heat tube device through which a working fluid can be circulated to transfer heat to air in a conventional air conditioning system. The heat tube device is disposable about a conventional cooling coil of the air conditioning system and includes a plurality of substantially U-shaped tubes connected to a support structure. The support structure includes members for allowing the heat tube device to be readily positioned about the cooling coil. An actuatable adjustment device is connected to the U-shaped tubes for allowing, upon actuation thereof, for the heat tubes to be simultaneously rotated relative to the cooling coil for allowing the heat transfer from the heat tube device to air in the air conditioning system to be selectively varied.

Khattar, Mukesh K. (inventor)

1990-01-01

259

Ceramic heat pipe development  

NASA Astrophysics Data System (ADS)

Ceramic materials used in conventional brickwork heat exchanger configurations increase allowable temperatures; however, joint leakage problems limit use of these designs. Ceramic tube heat exchanger designs reduce these problems but still require sliding joints and compliant tube end seals. Ceramic heat pipe based recuperator designs eliminate the sealing problems that limited the high temperature heat recovery installations. Heat pipe recuperators offer high corrosion and abrasion resistance, high temperature capability, reduced leakage, element redundancy, and simplified replacement and cleaning. The development of ceramic heat pipe recuperator elements involves the selection and test of materials and fabrication techniques having production potential, evaluation of technology in subscale tests, design and test of components for full scale recuperator applications, and demonstration of heat pipes in subscale and full scale recuperator installation.

Merrigan, M.

1980-09-01

260

Deployable Heat Pipe Radiator  

NASA Technical Reports Server (NTRS)

A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.

Edelstein, F.

1975-01-01

261

Nanofluid heat capacities  

NASA Astrophysics Data System (ADS)

Significant increases in the heat capacity of heat transfer fluids are needed not only to reduce the costs of liquid heating and cooling processes, but also to bring clean energy producing technologies like concentrating solar power (CSP) to price parity with conventional energy generation. It has been postulated that nanofluids could have higher heat capacities than conventional fluids. In this work, nano- and micron-sized particles were added to five base fluids (poly-? olefin, mineral oil, ethylene glycol, a mixture of water and ethylene glycol, and calcium nitrate tetrahydrate), and the resulting heat capacities were measured and compared with those of the neat base fluids and the weighted average of the heat capacities of the components. The particles used were inert metals and metal oxides that did not undergo any phase transitions over the temperature range studied. In the nanofluids studied here, we found no increase in heat capacity upon the addition of the particles larger than the experimental error.

Starace, Anne K.; Gomez, Judith C.; Wang, Jun; Pradhan, Sulolit; Glatzmaier, Greg C.

2011-12-01

262

Miniature Heat Pipes  

NASA Technical Reports Server (NTRS)

Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged "heat pipes" for space application. To control the extreme temperature ranges in space, heat pipes are important to spacecraft. The problem was to maintain an 8-watt central processing unit (CPU) at less than 90 C in a notebook computer using no power, with very little space available and without using forced convection. Thermacore's answer was in the design of a powder metal wick that transfers CPU heat from a tightly confined spot to an area near available air flow. The heat pipe technology permits a notebook computer to be operated in any position without loss of performance. Miniature heat pipe technology has successfully been applied, such as in Pentium Processor notebook computers. The company expects its heat pipes to accommodate desktop computers as well. Cellular phones, camcorders, and other hand-held electronics are forsible applications for heat pipes.

1997-01-01

263

Active microchannel heat exchanger  

DOEpatents

The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

Tonkovich, Anna Lee Y. (Pasco, WA) [Pasco, WA; Roberts, Gary L. (West Richland, WA) [West Richland, WA; Call, Charles J. (Pasco, WA) [Pasco, WA; Wegeng, Robert S. (Richland, WA) [Richland, WA; Wang, Yong (Richland, WA) [Richland, WA

2001-01-01

264

Integrated heat pipe-thermal storage design for a solar receiver. [Constant power source with heat from sun or from storage  

SciTech Connect

Light-weight heat pipe wall elements that incorporate a thermal storage subassembly within the vapor space are being developed as part of the Organic Rankine Cycle Solar Dynamic Power Systems (ORC-SDPS) receiver for the space station application. The operating temperature of he heat pipe elements is in the 770 to 810/sup 0/K range with a design power throughput of 4.8 kW per pipe. The total heat pipe length is 1.9 M. The Rankine cycle boiler heat transfer surfaces are positioned within the heat pipe vapor space, providing a relatively constant temperature input to the vaporizer. The heat pipe design employs axial arteries and distribution wicked thermal storage units with potassium as the working fluid. Stainless steel is used as the containment tube and screen material. Performance predictions for this configuration have been conducted and the design characterized as a function of artery geometry, distribution wick thickness, porosity, pore size, and permeability. Details of the analysis and of fabrication and assembly procedures are presented. 2 refs., 8 figs.

Keddy, E.S.; Sena, J.T.; Woloshun, K.; Merrigan, M.A.; Heidenreich, G.

1986-01-01

265

NREL Tests Integrated Heat Pump Water Heater Performance in Different Climates (Fact Sheet)  

SciTech Connect

This technical highlight describes NREL tests to capture information about heat pump performance across a wide range of ambient conditions for five heat pump water heaters (HPWH). These water heaters have the potential to significantly reduce water heater energy use relative to traditional electric resistance water heaters. These tests have provided detailed performance data for these appliances, which have been used to evaluate the cost of saved energy as a function of climate. The performance of HPWHs is dependent on ambient air temperature and humidity and the logic controlling the heat pump and the backup resistance heaters. The laboratory tests were designed to measure each unit's performance across a range of air conditions and determine the specific logic controlling the two heat sources, which has a large effect on the comfort of the users and the energy efficiency of the system. Unlike other types of water heaters, HPWHs are both influenced by and have an effect on their surroundings. Since these effects are complex and different for virtually every house and climate region, creating an accurate HPWH model from the data gathered during the laboratory tests was a main goal of the project. Using the results from NREL's laboratory tests, such as the Coefficient of Performance (COP) curves for different air conditions as shown in Figure 1, an existing HPWH model is being modified to produce more accurate whole-house simulations. This will allow the interactions between the HPWH and the home's heating and cooling system to be evaluated in detail, for any climate region. Once these modeling capabilities are in place, a realistic cost-benefit analysis can be performed for a HPWH installation anywhere in the country. An accurate HPWH model will help to quantify the savings associated with installing a HPWH in the place of a standard electric water heater. In most locations, HPWHs are not yet a cost-effective alternative to natural gas water heaters. The detailed system performance maps that were developed by this testing program will be used to: (1) Target regions of the country that would benefit most from this technology; (2) Identify improvements in current systems to maximize homeowner cost savings; and (3) Explore opportunities for development of advanced hot water heating systems.

Not Available

2012-01-01

266

A Write Head Integrated With a Solid-Immersion-Lens System for Heat-Assisted Magnetic Recording  

Microsoft Academic Search

We have developed for heat-assisted magnetic recording a novel write head in which a magnetic writer and a near-field optical lens system are integrated. The single-pole type (SPT) write head is embedded in the hemispherical lens of a solid immersion lens (SIL) system, which has an effective NA of 1.44 at a wavelength of 405 nm. The SPT head, which

Naoto Kojima; Naoki Ide; Yoshiyuki Urakawa; Masahiko Kaneko

2007-01-01

267

Prediction of heat transfer coefficient during condensation of water and R-134a on single horizontal integral-fin tubes  

Microsoft Academic Search

This paper presents a few salient features of an investigation carried out to study the heat transfer augmentation during condensation of water and R-134a vapor on horizontal integral-fin tubes. The experimental investigation was performed on two different experimental set-ups for water and R-134a. The test-sections were manufactured by machining fins over plain copper tubes of 24.4 ± 0.6 mm outside

Ravi Kumar; H. K. Varma; Bikash Mohanty; K. N. Agrawal

2002-01-01

268

Research on Heat Transfer Enhancement of Lubricating-Oil Cooler with Mixing Integral Pin-Fin Tubes and Plain Tubes  

Microsoft Academic Search

The design A lot of comparison experimental researches have been done to the lubricating-oil cooler with mixing integral pin-fin tubes and plain tubes double-flowing from an plain tubes lubricating-oil cooler. It is discovered that when oil volume flowing rate is same, exchanged heat per volume by the former is higher, and the pressure is lower, and the ability to transferred

Guang-lin Niu; Chang-qi Yan; Shuai Shi

2010-01-01

269

Electrical-Thermal Co-Simulation of 3D Integrated Systems With Micro-Fluidic Cooling and Joule Heating Effects  

Microsoft Academic Search

In this paper, the electrical-thermal co-simulation of 3DsystemswithJouleheating,fluidiccoolingandairconvectionef- fectsisproposed.Thefinite-volumemethodformulationsofvoltage distribution equation, heat equations for both fluid flow and solid medium with nonuniform mesh are explained in detail. Based on the proposed iterativeco-simulation method,package temperature distributionandvoltagedropwithJouleheatingandfluidiccooling effects can be estimated. Several packaging examples are simu- lated and the results show that with micro-channel fluidic cooling in high power density 3D integrated

Jianyong Xie; Madhavan Swaminathan

2011-01-01

270

Design and Assembly of an Integrated Metabolic Heat Regenerated Temperature Swing Adsorption (MTSA) Subassembly Engineering Development Unit  

NASA Technical Reports Server (NTRS)

Metabolic heat regenerated Temperature Swing Adsorption (MTSA) technology is being developed for thermal and carbon dioxide (CO2) control for a Portable Life Support System (PLSS), as well as water recycling. The core of the MTSA technology is a sorbent bed that removes CO2 from the PLSS ventilation loop gas via a temperature swing. A Condensing Ice Heat eXchanger (CIHX) is used to warm the sorbent while also removing water from the ventilation loop gas. A Sublimation Heat eXchanger (SHX) is used to cool the sorbent. Research was performed to explore an MTSA designed for both lunar and Martian operations. Previously each the sorbent bed, CIHX, and SHX had been built and tested individually on a scale relevant to PLSS operations, but they had not been done so as an integrated subassembly. Design and analysis of an integrated subassembly was performed based on this prior experience and an updated transient system model. Focus was on optimizing the design for Martian operations, but the design can also be used in lunar operations. An Engineering Development Unit (EDU) of an integrated MTSA subassembly was assembled based on the design. Its fabrication is discussed. Some details on the differences between the as-assembled EDU to the future flight unit are considered.

Padilla, Sebastian A.; Powers, Aaron; Iacomini, Christie S.; Paul, Heather L.

2011-01-01

271

Inhomogeneous temperature problems inside a Li\\/SOCl2 cell - Homogenization by integrated heat pipes  

Microsoft Academic Search

The effect of the temperature gradient on the electrical capacity of the lithium\\/thionyl chloride (Li\\/SOCl2) cells and the dependence of internal heat generation on the temperature level were investigated by studying the thermal behavior of a cell constituted by a number of couples stacken in a stainless steel cylinder during a discharge profile. It is shown that the temperature gradient

C. Lefriec; A. Suleiman; A. Alexandre

1992-01-01

272

Heat transfer in a 155 mm compound gun barrel with full length integral midwall cooling channels  

Microsoft Academic Search

When firing, large amounts of heat flow into the gun bore surfaces and result in wear and erosion of the gun bore. Moreover, the chamber surface temperature will reach the cook-off temperature of propellant during long sustained firing, which will impact on user safety and facilities. For large-caliber gun, a serious limitation on the weapon’s availability for action is imposed

Bin Wu; Gang Chen; Wei Xia

2008-01-01

273

Silicon Heat Pipe Array  

NASA Technical Reports Server (NTRS)

Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better suited for the cooling of semiconductor devices.

Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.

2013-01-01

274

Synthetic heat at mild temperatures.  

PubMed

"Synthetic heat", also known as the heat grill illusion, occurs when contact with spatially adjacent warm and cold stimuli produce a sensation of "heat". This phenomenon has been explained as a painful perception that occurs when warm stimulation inhibits cold-sensitive neurons in the spinothalamic tract (STT), which in turn unmasks activity in the pain pathway caused by stimulation of C-polymodal nociceptors (CPNs). The "unmasking model" was tested in experiment 1 by combining warm (35-40 degrees C) and cool (> or = 27 degrees C) stimuli that were too mild to stimulate CPNs. After discovering that these temperatures produced nonpainful heat, experiment 2 was designed to determine whether heat could be induced when near-threshold cooling was paired with mild warmth, and whether lowering the base temperature for cooling would increase the noxious (burning, stinging) components of heat for fixed cooling steps of 1-3 degrees C. Cooling by just 1 degrees C from a base temperature of 33 degrees C led to reports of heat on more than 1/3 of trials, and cooling by just 3 degrees C evoked heat on 75% of trials. Lowering the base temperature to 31 or 29 degrees C increased reports of heat and burning but did not produce significant reports of pain. Perception of nonpainful heat at such mild temperatures indicates either that cold-sensitive nociceptors with thresholds very similar to cold fibers innervate hairy skin in humans, or that heat can result from integration of warm fiber and cold fiber activity, perhaps via convergence on nonspecific (e.g., WDR) neurons in the STT. PMID:12088387

Green, Barry G

2002-01-01

275

Heat transfer from oriented heat exchange areas  

NASA Astrophysics Data System (ADS)

This paper deals with the transfer of heat-driven heat transfer surface area in relation to the construction of the criterion equation for "n" horizontal pipe one about another. On the bases of theoretical models have been developed for calculating the thermal performance of natural convection by Churilla and Morgan, for various pipe diameters and temperatures. These models were compared with models created in CFD-Fluent Ansys the same boundary conditions. The aim of the analyse of heat and fluxional pipe fields "n" pipes one about another at natural convection is the creation of criterion equation on the basis of which the heat output of heat transfer from pipe oriented areas one above another with given spacing could be quantified. At presence a sum of criterion equations exists for simple geometrical shapes of individual oriented geometrical areas but the criterion equation which would consider interaction of fluxional field generated by free convection from multiple oriented areas is not mentioned in standardly accessible technical literature and other magazine publications.

Vantuch, Martin; Huzvar, Jozef; Kapjor, Andrej

2014-03-01

276

Pacific Regional Solar Heating Handbook  

Microsoft Academic Search

A guide is given for engineers, architects, and individuals familiar with heating and ventilating applications, who wish to design a solar heating system for a residential or small commercial building in the Pacific Coast Region. Both air and liquid space heating systems and domestic hot water heating applications are presented in detail. Passive space heating and swimming pool heating systems

J. D. Balcomb; D. P. Grimmer; J. C. Hedstrom; K. C. Kerr

1976-01-01

277

Water-heating dehumidifier  

DOEpatents

A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.

Tomlinson, John J. (Knoxville, TN)

2006-04-18

278

Heat pipe development  

NASA Technical Reports Server (NTRS)

The objective of this program was to investigate analytically and experimentally the performance of heat pipes with composite wicks--specifically, those having pedestal arteries and screwthread circumferential grooves. An analytical model was developed to describe the effects of screwthreads and screen secondary wicks on the transport capability of the artery. The model describes the hydrodynamics of the circumferential flow in triangular grooves with azimuthally varying capillary menisci and liquid cross-sections. Normalized results were obtained which give the influence of evaporator heat flux on the axial heat transport capability of the arterial wick. In order to evaluate the priming behavior of composite wicks under actual load conditions, an 'inverted' glass heat pipe was designed and constructed. The results obtained from the analysis and from the tests with the glass heat pipe were applied to the OAO-C Level 5 heat pipe, and an improved correlation between predicted and measured evaporator and transport performance were obtained.

Bienart, W. B.

1973-01-01

279

Heat-pipe Earth.  

PubMed

The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics. PMID:24067709

Moore, William B; Webb, A Alexander G

2013-09-26

280

To Heat or Not to Heat?  

NSDL National Science Digital Library

Students are introduced to various types of energy with a focus on thermal energy and types of heat transfer as they are challenged to design a better travel thermos that is cost efficient, aesthetically pleasing and meets the design objective of keeping liquids hot. They base their design decisions on material properties such thermal conductivity, cost and function. These engineering and science concepts are paired with student experiences to build an understanding of heat transfer as it plays a role in their day-to-day lives. While this introduction only shows the top-level concepts surrounding the mathematics associated with heat transfer; the skills become immediately useful as students apply what they know to solve an engineering challenge.

CREAM GK-12 Program, Engineering Education Research Center, College of Engineering and Architecture,

281

NCSX Plasma Heating Methods  

SciTech Connect

The NCSX (National Compact Stellarator Experiment) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral-beam injection, and radio-frequency. Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The plan is to provide 3 MW of 50 keV balanced neutral-beam tangential injection with pulse lengths of 500 msec for initial experiments, and to be upgradeable to pulse lengths of 1.5 sec. Subsequent upgrades will add 3 MW of neutral-beam injection. This Chapter discusses the NCSX neutral-beam injection requirements and design issues, and shows how these are provided by the candidate PBX-M (Princeton Beta Experiment-Modification) neutral-beam injection system. In addition, estimations are given for beam-heating efficiencies, scaling of heating efficiency with machine size an d magnetic field level, parameter studies of the optimum beam-injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of radio-frequency heating by mode-conversion ion-Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron-cyclotron heating. The initial MCIBW heating technique and the design of the radio-frequency system lend themselves to current drive, so that if current drive became desirable for any reason only minor modifications to the heating system described here would be needed. The radio-frequency system will also be capable of localized ion heating (bulk or tail), and possibly ion-Bernstein-wave-generated sheared flows.

H.W. Kugel; D. Spong; R. Majeski; M. Zarnstorff

2003-02-28

282

NCSX Plasma Heating Methods  

SciTech Connect

The National Compact Stellarator Experiment (NCSX) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral beam injection, and radio-frequency (rf). Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, neutral beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The experimental plan requires 3 MW of 50-keV balanced neutral beam tangential injection with pulse lengths of 500 ms for initial experiments, to be upgradeable to pulse lengths of 1.5 s. Subsequent upgrades will add 3MW of neutral beam injection (NBI). This paper discusses the NCSX NBI requirements and design issues and shows how these are provided by the candidate PBX-M NBI system. In addition, estimations are given for beam heating efficiencies, scaling of heating efficiency with machine size and magnetic field level, parameter studies of the optimum beam injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of rf heating by mode conversion ion Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron cyclotron heating. The initial MCIBW heating technique and the design of the rf system lend themselves to current drive, so if current drive became desirable for any reason, only minor modifications to the heating system described here would be needed. The rf system will also be capable of localized ion heating (bulk or tail), and possiblyIBW-generated sheared flows.

H.W. Kugel, D. Spong, R. Majeski and M. Zarnstorff

2008-01-18

283

Mechanisms of Coronal Heating  

NASA Astrophysics Data System (ADS)

The Sun is a mysterious star. The high temperature of the chromosphere and corona present one of the most puzzling problems of solar physics. Observations show that the solar coronal heating problem is highly complex with many different facts. It is likely that different heating mechanisms are at work in solar corona. Recent observations show that Magnetic Carpet is a potential candidate for solar coronal heating.

Verma, S. R.

2006-09-01

284

Heat flow in Oklahoma  

Microsoft Academic Search

Twenty new heat flow values are incorporated, along with 40 previously published data, into a heat flow map of Oklahoma. The new heat flow data were estimated using previous temperature measurements in boreholes made by American Petroleum Institute researchers and 1,498 thermal conductivity measurements on drill cuttings. The mean of 20 average thermal gradients is 30.50sp°C\\/km. In general, thermal gradients

Constantin Cranganu

1997-01-01

285

Heat Loss Imagery  

NASA Technical Reports Server (NTRS)

Infrared scanning devices are being used to produce images that show, by color or black-and-white shading differences, which buildings and homes are losing heat to the outdoors, and how much. Heat loss surveys done by Texas Instruments, Daedalus Enterprises, Inc. and other companies have growing acceptance of their services among industrial firms, utilities, local governments, and state and federal agencies interested in promoting heat loss awareness and inspiring corrective actions.

1981-01-01

286

Saturn base heating handbook  

NASA Technical Reports Server (NTRS)

A handbook containing a summary of model and flight test base heating data from the S-1, S-1B, S-4, S-1C, and S-2 stages is presented. A review of the available prediction methods is included. Experimental data are provided to make the handbook a single source of Saturn base heating data which can be used for preliminary base heating design predictions of launch vehicles.

Mullen, C. R.; Bender, R. L.; Bevill, R. L.; Reardon, J.; Hartley, L.

1972-01-01

287

Heat Integration of the Water-Gas Shift Reaction System for Carbon Sequestration Ready IGCC Process with Chemical Looping  

SciTech Connect

Integrated gasification combined cycle (IGCC) technology has been considered as an important alternative for efficient power systems that can reduce fuel consumption and CO2 emissions. One of the technological schemes combines water-gas shift reaction and chemical-looping combustion as post gasification techniques in order to produce sequestration-ready CO2 and potentially reduce the size of the gas turbine. However, these schemes have not been energetically integrated and process synthesis techniques can be applied to obtain an optimal flowsheet. This work studies the heat exchange network synthesis (HENS) for the water-gas shift reaction train employing a set of alternative designs provided by Aspen energy analyzer (AEA) and combined in a process superstructure that was simulated in Aspen Plus (AP). This approach allows a rigorous evaluation of the alternative designs and their combinations avoiding all the AEA simplifications (linearized models of heat exchangers). A CAPE-OPEN compliant capability which makes use of a MINLP algorithm for sequential modular simulators was employed to obtain a heat exchange network that provided a cost of energy that was 27% lower than the base case. Highly influential parameters for the pos gasification technologies (i.e. CO/steam ratio, gasifier temperature and pressure) were calculated to obtain the minimum cost of energy while chemical looping parameters (oxidation and reduction temperature) were ensured to be satisfied.

Juan M. Salazara; Stephen E. Zitney; Urmila M. Diwekara

2010-01-01

288

Heat transfer equipment design  

NASA Astrophysics Data System (ADS)

A comprehensive presentation is made of state-of-the-art configurations and design methodologies for heat transfer devices applicable to industrial processes, automotive systems, air conditioning/refrigeration, cryogenics, and petrochemicals refining. Attention is given to topics in heat exchanger mechanical design, single-phase convection processes, thermal design, two-phase exchanger thermal design, heat-transfer augmentation, and rheological effects. Computerized analysis and design methodologies are presented for the range of heat transfer systems, as well as advanced methods for optimization and performance projection.

Shah, R. K.; Subbarao, Eleswarapu Chinna; Mashelkar, R. A.

289

Heat flux measurements  

NASA Technical Reports Server (NTRS)

A new automated, computer controlled heat flux measurement facility is described. Continuous transient and steady-state surface heat flux values varying from about 0.3 to 6 MW/sq m over a temperature range of 100 to 1200 K can be obtained in the facility. An application of this facility is the development of heat flux gauges for continuous fast transient surface heat flux measurement on turbine blades operating in space shuttle main engine turbopumps. The facility is useful for durability testing at fast temperature transients.

Liebert, Curt H.; Weikle, Donald H.

1989-01-01

290

Heat pipe technology issues  

SciTech Connect

Critical high temperature, high power applications in space nuclear power designs are near the current state of the art of heat pipe technology in terms of power density, operating temperature, and lifetime. Recent heat pipe development work at Los Alamos National Laboratory has involved performance testing of typical space reactor heat pipe designs to power levels in excess of 19 kW/cm/sup 2/ axially and 300 W/cm/sup 2/ radially at temperatures in the 1400 to 1500 K range. Operation at conditions in the 10 kW/cm/sup 2/ range has been sustained for periods of up to 1000 hours without evidence of performance degradation. The effective length for heat transport in these heat pipes was from 1.0 to 1.5 M. Materials used were molybdenum alloys with lithium employed as the heat pipe operating fluid. Shorter, somewhat lower power, molybdenum heat pipes have been life tested at Los Alamos for periods of greater than 25,000 hours at 1700 K with lithium and 20,000 hours at 1500/sup 0/K with sodium. These life test demonstrations and the attendant performance limit investigations provide an experimental basis for heat pipe application in space reactor design and represent the current state-of-the-art of high temperature heat pipe technology.

Merrigan, M.A.

1984-04-01

291

Heat and mass exchanger  

DOEpatents

A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

2007-09-18

292

Heat and mass exchanger  

DOEpatents

A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

2011-06-28

293

Heating Different Earth Materials  

NSDL National Science Digital Library

In this activity, students will be reminded that when sunlight strikes the Earth's surface, energy is absorbed and the surface material is heated. But although the same amount of sunlight strikes different materials at a given location, they heat up at different rates. Students will use models to demonstrate conduction, convection, and radiation and to gain an understanding about what happens to create our planet's weather, ocean currents, and other types of heat transfer. They will also shine a light on four different kinds of materials to examine their different rates of heating.

Passow, Michael

294

HEATS: Thermal Energy Storage  

SciTech Connect

HEATS Project: The 15 projects that make up ARPA-E’s HEATS program, short for “High Energy Advanced Thermal Storage,” seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

None

2012-01-01

295

Integrating artificial neural networks and empirical correlations for the prediction of water-subcooled critical heat flux  

Microsoft Academic Search

The critical heat flux (CHF) is an important parameter for the design of nuclear reactors, heat exchangers and other boiling heat transfer units. Recently, the CHF in water-subcooled flow boiling at high mass flux and subcooling has been thoroughly studied in relation to the cooling of high-heat-flux components in thermonuclear fusion reactors. Due to the specific thermal-hydraulic situation, very few

Alessandro Mazzola

1997-01-01

296

TRMM Validation: Integration of TRMM Satellite and Ground-Validation Data to Determine Tropical Heating  

NASA Technical Reports Server (NTRS)

Steiner and Houze showed from ground validation data that the Tropical Rain Measuring Mission (TRMM) satellite Precipitation Radar's (PR's) twice daily only sampling should lead to an uncertainty of approximately 20% in rain estimates. They further showed that the uncertainties are smallest at the 5-7.5 km level. Schumacher and Houze used Kwajalein ground validation data to show that the TRMM PR misses only 2.3% of the near surface rainfall but does not see 46% of the area where rain occurs, because of the 17 dBZ PR reflectivity threshold. Houze discusses how the TRMM data extend earlier tropical convective studies to global coverage of the vertical profile of latent heating via the TRMM PR''s ability to distinguish and globally map convective and stratiform precipitation. Process studies carried out under this TRMM grant Yuter and Houze and Yuter et al. studied ship-based radar observations in the tropical eastern Pacific ITCZ. The eastern Pacific precipitation process is different from the western Pacific (the COARE area); rain is heavier but the clouds are not as deep. These process differences may affect the ability to remotely sense precipitation accurately in the two regions. Satellite microwave data were able to detect the precipitation as long as the rain areas exceeded 10 km in dimension. However, the microwave algorithms had difficulty distinguishing light and heavy rain. Satellite IR algorithms only partially detected the rain because the tops of the smaller and more short-lived rain clouds were sometimes not cold enough for the IR algorithms to detect them. Houze et al. focused on the west Pacific precipitating mesoscale convective systems and showed how their precipitation and internal dynamics vary in relation to the slowly varying large-scale heating-driven circulation, which has a structure described by a combination of Kelvin and Rossby wave response to the near-equatorial convective heating constituted by the mesoscale convective systems. Ship and aircraft radar data were used in this study.

Houze, Robert A., Jr.

2001-01-01

297

Ultrasonic test application in geothermal heat exchangers and civil works to monitor the grout integrity (TUC)  

NASA Astrophysics Data System (ADS)

The working of a vertical geothermal probe, realized with a pipe U-tubes of high-density-polyethylene (HDPE) inserted in a grouted boreholes, is linked to the possibility to exchange heat with the surrounding soil. The concrete material useful for the borehole heat exchangers allows to satisfy a double purpose: sealing the polyethylene pipes from groundwater in the event of loss and increasing the thermal properties of the whole probe to provide a greater interaction with the underground. If this operation is not performed properly, the complete system may not satisfy the required heat demand, even with a well dimensioned installation, wasting the value of the entire carried out work. This paper offers to a wide group of professional actors a possible ultrasonic method of a draft and economically sustainable investigation for the identification of defects that could be present in the cementation realized inside a geothermal probe, but also in the realization of sonic piles. The instrument used for this type of test (TUC - Test Ultrasonic Cementation) has been designed and tested by the technicians of AG3, a Spin Off Company of Torino University, in collaboration with 3DM Electric and PASI companies, then subjected to patenting procedure (Patent Pending TO2011A000036). The main innovative feature of this approach has been the miniaturization of the equipment, able to investigate the geothermal probes with U-tubes with standard dimension (the maximum overall dimensions of the instruments detectors is 26 mm), maintaining a sampling rate appropriate to investigate the cementation and the early centimetres of the surrounding soil. The processing of the recorded data was performed by a dedicated Matlab software. In the first part of the article is presented the calibration process, that it was carried out through ad hoc creation of two situations likely to be investigated, while in the second part the paper reports the results obtained by the application of the TUC method to real case studies.

Mandrone, Giuseppe; Comina, Cesare; Giuliani, Andrea

2013-04-01

298

Failure analysis of a sodium heat pipe with integral lithium fluoride thermal energy storage  

NASA Astrophysics Data System (ADS)

A sodium, 321 stainless steel heat pipe with three filled Nb-1Zr tubes for thermal energy storage with 304 S.S. screen for wicking was thermal cycled to failure and then an analysis was performed to examine the failure. It was concluded that insufficient weld depth between an end cap and tube body permitted the propagation of a crack through a possible combination of thermal/corrosion failure, creep rupture of the end cap. A number of possible scenarios for the process following a leak are discussed.

Jacobson, D. L.; Soundararajan, P.

1985-09-01

299

A fully second order implicit/explicit time integration technique for hydrodynamics plus nonlinear heat conduction problems  

SciTech Connect

We present a fully second order implicit/explicit time integration technique for solving hydrodynamics coupled with nonlinear heat conduction problems. The idea is to hybridize an implicit and an explicit discretization in such a way to achieve second order time convergent calculations. In this scope, the hydrodynamics equations are discretized explicitly making use of the capability of well-understood explicit schemes. On the other hand, the nonlinear heat conduction is solved implicitly. Such methods are often referred to as IMEX methods. The Jacobian-Free Newton Krylov (JFNK) method (e.g. ) is applied to the problem in such a way as to render a nonlinearly iterated IMEX method. We solve three test problems in order to validate the numerical order of the scheme. For each test, we established second order time convergence. We support these numerical results with a modified equation analysis (MEA). The set of equations studied here constitute a base model for radiation hydrodynamics.

Kadioglu, Samet Y. [Multiphysics Methods Group, Reactor Physics Analysis and Design, Idaho National Laboratory, P.O. Box 1625, MS 3840, Idaho Falls, ID 83415 (United States)], E-mail: Samet.Kadioglu@inl.gov; Knoll, Dana A. [Multiphysics Methods Group, Reactor Physics Analysis and Design, Idaho National Laboratory, P.O. Box 1625, MS 3840, Idaho Falls, ID 83415 (United States)], E-mail: dana.knoll@inl.gov

2010-05-01

300

Savannah River reactor process water heat exchanger tube structural integrity margin Task Number 92-005-1  

Microsoft Academic Search

Twelve process water heat exchangers are designed to remove heat generated in the reactor tank. Each heat exchanger has approximately 9000, 1\\/2 inch diameter à 0.049 inches thick tubes. Minimum structural tubing requirements and the leak rate through postulated tubing defects are developed in this report A comparison of the structural requirements and the defect size calculated to produce leak

G. E. Mertz; D. M. Barnes; R. L. Sindelar

1992-01-01

301

Planetary heat flow measurements.  

PubMed

The year 2005 marks the 35th anniversary of the Apollo 13 mission, probably the most successful failure in the history of manned spaceflight. Naturally, Apollo 13's scientific payload is far less known than the spectacular accident and subsequent rescue of its crew. Among other instruments, it carried the first instrument designed to measure the flux of heat on a planetary body other than Earth. The year 2005 also should have marked the launch of the Japanese LUNAR-A mission, and ESA's Rosetta mission is slowly approaching comet Churyumov-Gerasimenko. Both missions carry penetrators to study the heat flow from their target bodies. What is so interesting about planetary heat flow? What can we learn from it and how do we measure it?Not only the Sun, but all planets in the Solar System are essentially heat engines. Various heat sources or heat reservoirs drive intrinsic and surface processes, causing 'dead balls of rock, ice or gas' to evolve dynamically over time, driving convection that powers tectonic processes and spawns magnetic fields. The heat flow constrains models of the thermal evolution of a planet and also its composition because it provides an upper limit for the bulk abundance of radioactive elements. On Earth, the global variation of heat flow also reflects the tectonic activity: heat flow increases towards the young ocean ridges, whereas it is rather low on the old continental shields. It is not surprising that surface heat flow measurements, or even estimates, where performed, contributed greatly to our understanding of what happens inside the planets. In this article, I will review the results and the methods used in past heat flow measurements and speculate on the targets and design of future experiments. PMID:16286290

Hagermann, Axel

2005-12-15

302

Integration and software for thermal test of heat rate sensors. [space shuttle external tank  

NASA Technical Reports Server (NTRS)

A minicomputer controlled radiant test facility is described which was developed and calibrated in an effort to verify analytical thermal models of instrumentation islands installed aboard the space shuttle external tank to measure thermal flight parameters during ascent. Software was provided for the facility as well as for development tests on the SRB actuator tail stock. Additional testing was conducted with the test facility to determine the temperature and heat flux rate and loads required to effect a change of color in the ET tank external paint. This requirement resulted from the review of photographs taken of the ET at separation from the orbiter which showed that 75% of the external tank paint coating had not changed color from its original white color. The paint on the remaining 25% of the tank was either brown or black, indicating that it had degraded due to heating or that the spray on form insulation had receded in these areas. The operational capability of the facility as well as the various tests which were conducted and their results are discussed.

Wojciechowski, C. J.; Shrider, K. R.

1982-01-01

303

Thermosyphon heat exchanger  

NASA Technical Reports Server (NTRS)

Report summarizes final development, testing, and certification of pumpless, liquid-to-air heat exchanger for solar heating. System requires blower but no pump in water loop. Output is 35,000 Btu/hr when water temperature is 49 C.

Hankins, J. D.

1980-01-01

304

Heat pipe investigations  

NASA Technical Reports Server (NTRS)

Techniques associated with thermal-vacuum and bench testing, along with flight testing of the OAO-C spacecraft heat pipes are outlined, to show that the processes used in heat transfer design and testing are adequate for good performance evaluations.

Marshburn, J. P.

1973-01-01

305

Heat flux converter  

Microsoft Academic Search

(usually by means of glue or putty). The operation of such a converter is based upon measurement of the entire quantity of heat which enters it from the start of the process. Strict fulfillment of the latter condition is guaranteed by a choice of thickness of the calorimeter such that its inner surface is heated just so much during the

B. I. Bakum; L. V. Novikov; Yu. V. Yakhlakov

1968-01-01

306

Mechanisms of Coronal Heating  

Microsoft Academic Search

The Sun is a mysterious star. The high temperature of the chromosphere and corona present one of the most puzzling problems of solar physics. Observations show that the solar coronal heating problem is highly complex with many different facts. It is likely that different heating mechanisms are at work in solar corona. Recent observations show that Magnetic Carpet is a

S. R. Verma

2006-01-01

307

Reykjavik District Heating System.  

National Technical Information Service (NTIS)

Reykjavik, Iceland, utilizes natural geothermal resources as the heat input for its district heating system. This system served about 8,700 of the 10,000 residences in 1970. The water used is non-corrosive, allowing the use of standard pipe and fittings. ...

J. Zoega G. Kristinsson

1970-01-01

308

Rapid Acclimatization to Heat.  

National Technical Information Service (NTIS)

The authors have established a procedure to replace part of the daily heat exposures required in the conventional routine acclimatization, with stints of climbing exercise, thus allowing to save in time and heated space when large number of persons have t...

E. Kamon

1974-01-01

309

Solar heat collector panel  

Microsoft Academic Search

A molded plastic base has longitudinally extended channels, with the channel walls being relieved at laterally spaced locations to define closely spaced posts which support a transparent cover. A flat metal heat absorbing plate is provided just below the cover, and has holes for loosely receiving the posts. A corrugated plate is welded to the underside of the heat absorbing

Hojnowski

1976-01-01

310

Heat-producing flowers  

Microsoft Academic Search

The flowers of some plants produce enough heat to raise their temperatures as much as 35°C above air temperature. Three species have been shown to regulate flower temperature within a narrow range by an unknown physiological mechanism that increases the rate of heat production as air temperature decreases. Thermogenic plants occur only in ancient families of seed plants, and have

Roger S. Seymour; Paul Schultze-Motel

1997-01-01

311

Electric Heating Load Analysis  

Microsoft Academic Search

The accurate prediction of load characteristics-maximum daily load cycles as well as annual energy usage-is essential for the development of the electric space heating market by electric utilities. Adequate measurements of existing installations, the most reliable method of load analysis, is impossible for new heating device concepts or if the installations do not exist. A commonly used method of load

Richard F. Cook

1965-01-01

312

Plumbing and Heating Curriculum.  

ERIC Educational Resources Information Center

Theory and experience in the following areas are included in this plumbing curriculum: (1) plumbing fixtures and heating; (2) city water service; (3) fixture roughing; (4) venting; and (5) solar heating systems. The plumbing program manual includes the following sections: (1) general objectives for grades 10, 11, and 12; (2) a list of 33 major…

EASTCONN Regional Educational Services Center, North Windham, CT.

313

Scraped surface heat exchangers.  

PubMed

Scraped surface heat exchangers (SSHEs) are commonly used in the food, chemical, and pharmaceutical industries for heat transfer, crystallization, and other continuous processes. They are ideally suited for products that are viscous, sticky, that contain particulate matter, or that need some degree of crystallization. Since these characteristics describe a vast majority of processed foods, SSHEs are especially suited for pumpable food products. During operation, the product is brought in contact with a heat transfer surface that is rapidly and continuously scraped, thereby exposing the surface to the passage of untreated product. In addition to maintaining high and uniform heat exchange, the scraper blades also provide simultaneous mixing and agitation. Heat exchange for sticky and viscous foods such as heavy salad dressings, margarine, chocolate, peanut butter, fondant, ice cream, and shortenings is possible only by using SSHEs. High heat transfer coefficients are achieved because the boundary layer is continuously replaced by fresh material. Moreover, the product is in contact with the heating surface for only a few seconds and high temperature gradients can be used without the danger of causing undesirable reactions. SSHEs are versatile in the use of heat transfer medium and the various unit operations that can be carried out simultaneously. This article critically reviews the current understanding of the operations and applications of SSHEs. PMID:16527753

Rao, Chetan S; Hartel, Richard W

2006-01-01

314

Nonequilibrium heat capacity  

NASA Astrophysics Data System (ADS)

Development of steady state thermodynamics and statistical mechanics depends crucially on our ability to extend the notions of equilibrium thermodynamics to nonequilibrium steady states (NESS). The present paper considers the extension of heat capacity. A modified definition is proposed which continues to maintain the same relation to steady state Shannon entropy as in equilibrium, thus providing a thermodynamically consistent treatment of NESS heat capacity.

Mandal, Dibyendu

2013-12-01

315

Solar water heating system  

Microsoft Academic Search

A solar water heating system is described in which piping arrangements and solenoid operated valves are combined with a water storage heater and solar heater or collectors in a manner to protect the system against over temperature and against freezing without the use of antifreeze or auxiliary heat exchanger systems.

Cook

1978-01-01

316

The Earth's Heat Budget  

NSDL National Science Digital Library

Hands-on laboratory activity that allows students to investigate the effects of distance and angle on the input of solar radiation at Earth's surface, the role played by albedo, the heat capacity of land and water, and how these cause the seasons. Students predict radiative heating based on simple geometry and experiment to test their hypotheses.

Plotnick, Roy; Teachers, National A.

317

Silicon carbide heating elements  

Microsoft Academic Search

Silicon carbide is widely used as an electrical heating element because of its excellent thermal and mechanical properties and its electrical resistivity. However, the increase of the electrical resistivity with running time and temperature limits the industrial development of the SiC heating elements. The processes responsible for ageing are not well understood, but it is generally assumed that this phenomena

K. Pelissier; T. Chartier; J. M. Laurent

1998-01-01

318

Heat It Up!  

NSDL National Science Digital Library

Through a teacher demonstration using water, heat and food coloring, students see how convection moves the energy of the Sun from its core outwards. Students learn about the three different modes of heat transfer (convection, conduction, radiation) and how they are related to the Sun and life on our planet.

Integrated Teaching And Learning Program

319

Electrostatic heat flux instabilities  

NASA Technical Reports Server (NTRS)

The electrostatic cyclotron and ion acoustic instabilities in a plasma driven by a combined heat flux and current were investigated. The minimum critical heat conduction speed (above which the plasma is unstable) is given as a function of the ratio of electron to ion temperatures.

Morrison, P. J.; Ionson, J. A.

1980-01-01

320

Chemical heat pump  

DOEpatents

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

1981-01-01

321

Chemical heat pump  

DOEpatents

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate intallation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

1984-01-01

322

Chemical heat pump  

DOEpatents

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to faciliate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

1984-01-01

323

Chemical heat pump  

DOEpatents

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

1984-01-01

324

Introductory heat-transfer  

NASA Technical Reports Server (NTRS)

The objective is to introduce some concepts of thermodynamics in existing heat-treating experiments using available items. The specific objectives are to define the thermal properties of materials and to visualize expansivity, conductivity, heat capacity, and the melting point of common metals. The experimental procedures are described.

Widener, Edward L.

1992-01-01

325

Heat transfer in a pulsating heat pipe with open end  

Microsoft Academic Search

Heat transfer in the evaporator and condenser sections of a pulsating heat pipe (PHP) with open end is modeled by analyzing thin film evaporation and condensation. The heat transfer solutions are applied to the thermal model of the pulsating heat pipe and a parametric study was performed. The results show that the heat transfer in a PHP is mainly due

Yuwen Zhang; Amir Faghri

2002-01-01

326

Heat pipes and use of heat pipes in furnace exhaust  

DOEpatents

An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

Polcyn, Adam D. (Pittsburgh, PA) [Pittsburgh, PA

2010-12-28

327

Heat pipe development status  

SciTech Connect

Test heat pipes have been operated in the 1400 K to 1700 K range for periods in excess of 20,000 hours with the objective of understanding and controlling corrosion and failure mechanisms. The results of a post test analysis of one of these heat pipes that was operated for 25,216 hours at 1700 K are reviewed and the implications for heat pipe lifetime discussed. An in-process report of an investigation of transient heat pipe behavior is presented. This investigation is being conducted as a result of restart problems encountered during life test of a 2 m. radiation cooled heat pipe. The results of a series of shut-down tests from power and temperature are given and probable causes of the restart problem discussed.

Merrigan, M.A.

1984-01-01

328

Silica heat shield sizing  

NASA Technical Reports Server (NTRS)

The sensitivity of silica heat shield requirements to gap width, tile edge radius, and heat transfer distribution within tile gaps was investigated. A two-dimensional thermal model was modified and used to determine the effect of two dimensional heat transfer distributions at high temperature reusable surface insulation edges on shuttle thermal protection system (TPS) requirements. The sensitivity of TPS requirements to coating thickness, emissivity, substructure thickness, and changes in gap heating for several locations on shuttle was also studied. An inverse solution technique was applied to temperature data obtained in the Ames 20 MW turbulent duct in order to examine the effect of tile edge radius on TPS requirements. The derived heating values were then used to predict TPS requirements. Results show that increasing tile radius reduces TPS requirements.

Ebbesmeyer, L. H.; Christensen, H. E.

1975-01-01

329

Heat Island Effect  

NSDL National Science Digital Library

For people living in and around cities, heat islands are of growing concern. This phenomenon describes urban and suburban temperatures that are 2 to 10 degrees F (1 to 6 degrees C) hotter than nearby rural areas. Elevated temperatures can impact communities by increasing peak energy demand, air conditioning costs, air pollution levels, and heat-related illness and mortality. The materials available here describe the basic causes of the heat island effect, and what can be done to mitigate some of the impacts. There is also an overview of the Urban Heat Island Pilot Project (UHIPP), an initiative being conducted in five cities in the U.S. to adopt and evaluate heat island reduction strategies and programs.

330

Heat Flow Measurement  

NASA Technical Reports Server (NTRS)

Heat gauges are used to measure heat flow in industrial activities. They must periodically be certified by instruments designed to provide a heat flux measurement standard. CSTAR, a NASA CCDS, and REMTECH have developed a portable heat flux checker/calibrator. The Q-CHEC can be carried to the heat gauge for certification, reducing out of service time for the gauge and eliminating the need for a replacement gauge during certification. It can provide an "end-to-end" check of the instrumentation measurement system or be used as a standalone calibrator. Because Q-CHEC offers on-site capability to detect and eliminate measurement errors, measurements do not have to be repeated, and money is saved.

1993-01-01

331

Heat Pipe Systems  

NASA Technical Reports Server (NTRS)

The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.

1993-01-01

332

Knudsen heat capacity  

NASA Astrophysics Data System (ADS)

We present a "Knudsen heat capacity" as a more appropriate and useful fluid property in micro/nanoscale gas systems than the constant pressure heat capacity. At these scales, different fluid processes come to the fore that are not normally observed at the macroscale. For thermodynamic analyses that include these Knudsen processes, using the Knudsen heat capacity can be more effective and physical. We calculate this heat capacity theoretically for non-ideal monatomic and diatomic gases, in particular, helium, nitrogen, and hydrogen. The quantum modification for para and ortho hydrogen is also considered. We numerically model the Knudsen heat capacity using molecular dynamics simulations for the considered gases, and compare these results with the theoretical ones.

Babac, Gulru; Reese, Jason M.

2014-05-01

333

Solar heating system  

DOEpatents

An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

Schreyer, James M. (Oak Ridge, TN); Dorsey, George F. (Concord, TN)

1982-01-01

334

Improved solar heating systems  

DOEpatents

An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

Schreyer, J.M.; Dorsey, G.F.

1980-05-16

335

Cross-Beam Energy Transfer (CBET) Effect with Additional Ion Heating Integrated into the 2-D Hydrodynamics Code DRACO  

NASA Astrophysics Data System (ADS)

The cross-beam energy transfer (CBET) effect causes pump and probe beams to exchange energy via stimulated Brillouin scattering.footnotetext W. L. Kruer, The Physics of Laser--Plasma Interactions, Frontiers in Physics, Vol. 73, edited by D. Pines (Addison-Wesley, Redwood City, CA, 1988), p. 45. The total energy gained does not, in general, equate to the total energy lost; the ion-acoustic wave comprises the residual energy balance, which can decay, resulting in ion heating.footnotetext E. A. Williams et al., Phys. Plasmas 11, 231 (2004). The additional ion heating can retune the conditions for CBET affecting the overall energy transfer as a function of time. CBET and the additional ion heating are incorporated into the 2-D hydrodynamics code DRACOfootnotetext P. B. Radha et al., Phys. Plasmas 12, 056307 (2005). as an integral part of the 3-D ray trace where CBET is treated self-consistently within on the hydrodynamic evolution. DRACO simulation results employing CBET will be discussed. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-08NA28302.

Marozas, J. A.; Collins, T. J. B.

2012-10-01

336

Varmepumpe med energiabsorber som varmeoptager. (Heat pumps and energy-absorber as heat absorbers).  

National Technical Information Service (NTIS)

With regard to heat pumps with uncovered solar collectors as the only heat absorbers, very high temperatures (> 50 deg. centigrade) can arise in the latter during the summer. Other problems are constructional damage when the solar collector is integrated ...

H. C. Aagaard

1992-01-01

337

Integrated use of solar panels and a waste heat scavenger. Progress report  

SciTech Connect

The objectives of this project were to: (1) install energy measurement devices on commercially available solar collectors and a heat scavenger attached to the dairy refrigeration system; and (2) make the results of the demonstration available to other dairy farmers. The objectives have been accomplished. Measurement devices have been installed and are currently establishing a data base on system performance. A demonstration for dairy farmers was sponsored by the Agricultural Economics Department and the Agricultural Engineering Extension Department of the University of Georgia. The demonstration and associated program was held in November of 1980 at Monroe, Georgia which is near the demonstration dairy. A tour of the dairy followed presentation of energy related topics. About 60 farmers attended this program. A copy of the program and a summary of experience with the system are attached.

Jarrell, J.H.; Miller, B.R.; Smathers, W.M. Jr.

1980-01-01

338

Oscillating-Coolant Heat Exchanger  

NASA Technical Reports Server (NTRS)

Devices useful in situations in which heat pipes inadequate. Conceptual oscillating-coolant heat exchanger (OCHEX) transports heat from its hotter portions to cooler portions. Heat transported by oscillation of single-phase fluid, called primary coolant, in coolant passages. No time-averaged flow in tubes, so either heat removed from end reservoirs on every cycle or heat removed indirectly by cooling sides of channels with another coolant. Devices include leading-edge cooling devices in hypersonic aircraft and "frost-free" heat exchangers. Also used in any situation in which heat pipe used and in other situations in which heat pipes not usable.

Scotti, Stephen J.; Blosser, Max L.; Camarda, Charles J.

1992-01-01

339

Heat flow in Oklahoma  

NASA Astrophysics Data System (ADS)

Twenty new heat flow values are incorporated, along with 40 previously published data, into a heat flow map of Oklahoma. The new heat flow data were estimated using previous temperature measurements in boreholes made by American Petroleum Institute researchers and 1,498 thermal conductivity measurements on drill cuttings. The mean of 20 average thermal gradients is 30.50sp°C/km. In general, thermal gradients increase from SW (14.11sp°C/km) to NE (42.24sp°C/km). The range of 1,498 in situ thermal conductivity measurements (after corrections for anisotropy, in situ temperature, and porosity) is 0.90-6.1 W/m-K; the average is 1.68 W/m-K. Estimated near-surface heat flow (±20%) at 20 new sites in Oklahoma varies between 22 ± 4 mW/msp2 and 86 ± 17 mW/msp2; the average is 50 mW/msp2. Twenty-seven new heat-generation estimates, along with 22 previously published data, are used to create a heat generation map of Oklahoma. The range of heat production estimates is 1.1-3.5 muW/msp3, with an average of 2.5 muW/msp3. The heat flow regime in Oklahoma is primarily conductive in nature, except for a zone in northeast. Transient effects due to sedimentary processes and metamorphic/igneous activity, as well as past climatic changes, do not significantly influence the thermal state of the Oklahoma crust. Heat flow near the margins of the Arkoma and Anadarko Basins may be depressed or elevated by 5-13 mW/msp2 by refraction of heat from sedimentary rocks of relatively low thermal conductivity (1-2 W/m-K) into crystalline basement rocks of relatively high thermal conductivity (˜3-4 W/m-K). The heat generation-heat flow relationship shows a modest correlation. The relatively high heat flow (˜70-80 mW/msp2) in part of northeastern Oklahoma suggests that the thermal regime there may be perturbed by regional groundwater flow originating in the fractured outcrops of the Arbuckle-Simpson aquifer in the Arbuckle Mountains.

Cranganu, Constantin

340

Glovebox heat test.  

SciTech Connect

An existing argon atmosphere glovebox enclosure was to be refurbished for contaminated operations with a large, high temperature induction furnace. Thermal modeling indicated that glovebox temperatures would be high but acceptable without active cooling, but there were significant concerns that the analysis was inadequate and active cooling would be required. In particular, radiant heating of the glovebox walls by the furnace and pressure control system performance were concerns the thermal model had not addressed. Consequently, a thermal load test with a simulated furnace was designed to answer these questions. The purpose of the test was to determine if active cooling would be required to maintain containment integrity and, if not required, would it still be desirable for improved operations?

Bushnell, C. G.; Rigg, R. H.; Solbrig, C. W.

2002-08-21

341

Effect of a probiotic mixture on intestinal microflora, morphology, and barrier integrity of broilers subjected to heat stress.  

PubMed

The current study investigated the efficacy of a probiotic mixture on ameliorating heat stress-induced impairment of intestinal microflora, morphology, and barrier integrity in broilers. The probiotic mixture contained Bacillus licheniformis, Bacillus subtilis, and Lactobacillus plantarum. Three hundred sixty 21-d-old Ross 308 male broilers were allocated in 4 experimental treatments, each of which was replicated 6 times with 15 broilers per replicate. A 2 × 2 factorial design was used in the study, and the main factors were composed of diet (basal diet or addition of 1.5 g/kg of probiotic mixture) and temperature (thermoneutral zone or heat stress). From d 22 to 42, birds were either raised in a thermoneutral zone (22°C) or subjected to cyclic heat stress by exposing them to 33°C for 10 h (from 0800 to 1800) and 22°C from 1800 to 0800. Compared with birds kept in the thermoneutral zone, birds subjected to heat stress had reduced ADG and ADFI; lower viable counts of Lactobacillus and Bifidobacterium and increased viable counts of coliforms and Clostridium in small intestinal contents; shorter jejunal villus height, deeper crypt depth, and lower ratio of villus height to crypt depth; decreased jejunal transepithelial electrical resistance and a higher level of jejunal paracellular permeability of fluorescein isothiocyanate dextran 4 kDa; and downregulated protein levels of occludin and zonula occludens-1 (P < 0.05). Supplemental probiotics increased (P < 0.05) small intestinal Lactobacillus and Bifidobacterium, jejunal villus height, protein level of occludin, and decreased (P < 0.05) feed to gain ratio and small intestinal coliforms. These results indicate that dietary addition of probiotic mixture was effective in partially ameliorating intestinal barrier function. But no temperature × diet interaction was observed in the present study, revealing that the supplemented probiotics had the same effect at both temperatures. PMID:24604851

Song, J; Xiao, K; Ke, Y L; Jiao, L F; Hu, C H; Diao, Q Y; Shi, B; Zou, X T

2014-03-01

342

Passive oscillatory heat transport systems  

Microsoft Academic Search

An underdeveloped class of oscillatory passive heat transport cycles are discussed that have the potential to transport significantly higher heat loads than current heat pipes. Prototype cycles employing inferior working fluids have demonstrated transport of higher heat loads over significantly greater distances than similarly sized heat pipes (including CPLs and LHPs) employing ammonia. Most of the proposed cycles do not

Mark M. Weislogel

2002-01-01

343

Advanced Regenerative Heat Recovery System.  

National Technical Information Service (NTIS)

A new concept heat wheel regenerator has been developed to recover heat from a wide range of industrial heating processes. The heat wheel design separates the heat transfer matrix from the areas to be sealed so that better sealing performance can be expec...

R. G. Whitbeck

1984-01-01

344

Heat Sources for District Heating for Atlantic City.  

National Technical Information Service (NTIS)

The results of a study of heat sources for district heating for a proposed district heating system for Atlantic City are presented. Both solid waste incineration and cogeneration were considered in detail. Other sources were very briefly considered and ei...

1982-01-01

345

Heat recovery apparatus  

SciTech Connect

Heat transfer is a living science and technical advances are constantly being made. However, in many cases, progress is limited by the equipment that is available on the market, rather than by knowledge of the heat transfer process. A case in point is the design of economizers: in such equipment a small quantity of water (with a relatively good heat transfer coefficient) is heated by a large quantity of low-pressure gas (with an inherently low heat transfer coefficient). As a first step in design finned tubing is used to lessen the discrepancy in coefficients. From this point, it becomes apparent that the equipment consists of a small number of tubes (to maintain good velocity on the water side) of considerable length (to provide sufficient area). In the process industries the base pressure, though low, may be in the region of 0.5 bar, and there is no convenient flue in which to place the heat recovery coil. It is therefore contained in a flat-sided enclosure, which is ill-fitted to pressure containment and is therefore reinforced with a plethora of structural sections. Such inelegant construction is quite common in North America; in Europe, cylindrical containments of vast size have been supplied for the same purposes. The real shortcoming is a successful marriage of different disciplines to produce reliable and efficient heat transfer equipment suitably contained.

McFarland, I.

1987-01-01

346

Heat flux sensor calibrator  

NASA Astrophysics Data System (ADS)

The heat flux to space shuttle main engine (SSME) turbopump turbine blades may be as high as 10 to the 7th power. The heat flux causes thermal transients that are of the order of 1 sec as temperature varies from perhaps 1500 K to 100 K. It is suspected that these transients cause durability problems in the turbine blades. To quantitatively evaluate the effect of these transients, heat flux sensors or gauges were developed to obtain data to verify analytical models. The objective is to design and fabricate a system for steady state and transient calibration and durability testing of heat flux sensors for use in SSME turbine blades. The calibrator consists of: (1) the arc lamp, (2) a high speed positioning table for placing standard and special heat flux sensors in the incident beam of radiant heat flux, (3) provision for cooling the blade and special sensors inserted in the blade, (4) a computer for controlling the positioning table, storing electrical output values from sensors, and calculating heat flux from these values, and (5) a pyrometer for measuring sensor surface temperatures.

Liebert, C. H.

1985-05-01

347

Fundamental heat transfer experiments of heat pipes for turbine cooling  

SciTech Connect

Fundamental heat transfer experiments were carried out for three kinds of heat pipes that may be applied to turbine cooling in future aero-engines. In the turbine cooling system with a heat pipe, heat transfer rate and start-up time of the heat pipe are the most important performance criteria to evaluate and compare with conventional cooling methods. Three heat pipes are considered, called heat pipe A, B, and C, respectively. All heat pipes have a stainless steel shell and nickel sintered powder metal wick. Sodium (Na) was the working fluid for heat pipes A and B; heat pipe C used eutectic sodium-potassium (NaK). Heat pipes B and C included noncondensible gas for rapid start-up. There were fins on the cooling section of heat pipes. In the experiments, an infrared image furnace supplied heat to the heat pipe simulating turbine blade surface conditions. In the results, heat pipe B demonstrated the highest heat flux of 17 to 20 W/cm{sup 2}. The start-up time was about 6 minutes for heat pipe B and about 6 minutes for heat pipe A. Thus, adding noncondensible gas effectively reduced start-up time. Although NaK is a liquid phase at room temperature, the start-up time of heat pipe C (about 7 to 8 minutes) was not shorter than the heat pipe B. The effect of a gravitational force on heat pipe performance was also estimated by inclining the heat pipe at an angle of 90 deg. There was no significant gravitational dependence on heat transport for heat pipes including noncondensible gas.

Yamawaki, S. [Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo (Japan); Yoshida, T.; Taki, M.; Mimura, F. [National Aerospace Lab., Tokyo (Japan)

1998-07-01

348

[Clothing and heat disorder].  

PubMed

The influence of the clothing material properties(like water absorbency and rapid dryness, water vapor absorption, water vapor permeability and air permeability) and the design factor of the clothing(like opening condition and fitting of clothing), which contributed to prevent heat disorder, was outlined. WBGT(wet-bulb globe temperature) is used to show a guideline for environmental limitation of activities to prevent heat disorder. As the safety function is more important than thermal comfort for some sportswear and protective clothing with high cover area, clothing itself increases the risk of heat disorder. WBGT is corrected by CAF (clothing adjustment factor) in wearing such kind of protective clothing. PMID:22690609

Satsumoto, Yayoi

2012-06-01

349

Teachers' Domain: Heat Transfer  

NSDL National Science Digital Library

This item is an interactive Flash animation for Grades 5-8 on the topic of heat. Users explore methods of heat transfer and classify examples from everyday life. Three methods of heat transfer are depicted: conduction, convection, and radiation. Teachers' Domain is an NSF-funded pathway of the National Science Digital Library (NSDL). It is a growing collection of more than 1,000 free educational resources compiled by researchers and experienced teachers to promote the use of digital resources in the classroom.

2008-10-21

350

Heat treatment study 2  

NASA Technical Reports Server (NTRS)

The microstructural variations in nickel based superalloys that result from modifications in processing were examined. These superalloys include MAR-M246(HF) and PWA1480. Alternate heat treatments for equiaxed as-cast specimens were studied and a sample matrix of 42 variations in the heat treatments were processed, as well as different directional solidification parameters. Variation in temperature and times for both solution and aging were performed. Photomicrographs were made of the microstructure and volume fraction analysis of primary gamma-prime and aged gamma-prime precipitates were performed. The results of the heat treatment, cooling rate, and directional solidification experiments are discussed.

Workman, Gary L.

1990-01-01

351

Heating and cooling  

SciTech Connect

Why pay for energy when there`s a free stockpile of it right under your feet? With the help of a geothermal heat pump system, one can extract that energy from the ground and put it to good use, lowering heating and cooling costs. From private homes to public schools and fast-food restaurants, an increasing number of establishments are turning to geothermal heat pump systems for space conditioning. Experts say 1998 is already proving to be the best year yet for the technology, and they foresee an even more promising future. Some examples of geothermal energy use are given.

Lamarre, L.

1998-05-01

352

Prototype solar heating and combined heating and cooling systems  

NASA Technical Reports Server (NTRS)

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.

1977-01-01

353

Solar dynamic heat receiver technology  

NASA Technical Reports Server (NTRS)

A full-size, solar dynamic heat receiver was designed to meet the requirements specified for electrical power modules on the U.S. Space Station, Freedom. The heat receiver supplies thermal energy to power a heat engine in a closed Brayton cycle using a mixture of helium-xenon gas as the working fluid. The electrical power output of the engine, 25 kW, requires a 100 kW thermal input throughout a 90 minute orbit, including when the spacecraft is eclipsed for up to 36 minutes from the sun. The heat receiver employs an integral thermal energy storage system utilizing the latent heat available through the phase change of a high-temperature salt mixture. A near eutectic mixture of lithium fluoride and calcium difluoride is used as the phase change material. The salt is contained within a felt metal matrix which enhances heat transfer and controls the salt void distribution during solidification. Fabrication of the receiver is complete and it was delivered to NASA for verification testing in a simulated low-Earth-orbit environment. This document reviews the receiver design and describes its fabrication history. The major elements required to operate the receiver during testing are also described.

Sedgwick, Leigh M.

1991-01-01

354

Extreme Heat and Your Health  

MedlinePLUS

... Stay Cool in Extreme Heat Feature #2 - CDC's Tracking Program: Making Missouri Cooling Centers Easy to Find ... BAM! Body and Mind (Safety Guidance for Kids) Tracking Network/Extreme Heat Extreme Heat Infographic PSAs and ...

355

Innovation: the induction heated screw.  

National Technical Information Service (NTIS)

The Research and Development Division at EDF has developed an original technique for heating, drying or baking powder products: the induction heated Archimedes screw. Its main characteristic is simultaneous heating of the screw and the sleeve. (author). 4...

B. Paya

1993-01-01

356

Integrated parameter estimation of multi-component thermal systems with demonstration on a combined heat and power system.  

PubMed

In experimental models of multi-component thermal systems, small errors in each submodel can propagate detrimentally through the overall model, resulting in large prediction errors as the prediction time increases. These errors can be problematic when using open-loop or feed-forward control schemes. This paper demonstrates the advantages of a whole-system or integrated parameter estimation approach as opposed to the component-by-component parameter estimation approach that is widespread in the literature. The approach is demonstrated on a combined heat and power system at a laboratory facility, and the resulting model is used to predict the system temperatures up to 20 min in advance. Results show that, when compared to conventional component-by-component parameter estimation, the integrated parameter estimation approach improves the model prediction accuracy significantly. PMID:22503465

Smith, Aaron; Luck, Rogelio; Mago, Pedro J

2012-07-01

357

Homogenization heat treating cast microstructure  

NSDL National Science Digital Library

Cast microstructures have variations in composition on the length scale of dendrites and homogenization heat treatments are performed to smooth out these variations. This problem is an integral analysis of the 1D diffusion mass transfer in this problem. The results using two different assumed profiles are compared.

Krane, Matthew J.

2008-10-25

358

FTR Europia Gamma Heating.  

National Technical Information Service (NTIS)

Calculated and experimental gamma heating rates of europia in the Engineering Mockup Critical Assembly (EMC) were correlated. A calculated to experimental (C/E) ratio of 1.086 was established in validating the theoretical approach and computational techni...

J. T. Ward

1975-01-01

359

Advanced heat pump cycle  

SciTech Connect

The desorption and absorption process of a vapor compression heat pump with a solution circuit (VCHSC) proceeds at gliding temperature intervals, which can be adjusted over a wide range. In case that the gliding temperature intervals in the desorber and the absorber overlap, a modification of the VCHSC employing a desorber/absorber heat exchange (DAHX) can be introduced, which results in an extreme reduction of the pressure ratio. Although the DAHX-cycle has features of a two-stage cycle, it still requires only one solution pump, one separator and one compressor. Such a cycle for the working pair ammonia/water is built in the Energy Laboratory of the Center for Environmental Energy Engineering at the University of Maryland. The experimental results obtained with the research plant are discussed and compared to those calculated with a simulation program. The possible temperature lift between heat source and heat sink depending on the achievable COP are presented.

Groll, E.A.; Radermacher, R.

1993-07-01

360

Bituminous Heat Insulating Materials.  

National Technical Information Service (NTIS)

The project envisages energy savings in the heating of civil and industrial buildings with the use of improved insulating materials, e.g. waterproofed against humidity and water vapor and protected against the attack of polluting agents in the atmosphere,...

L. Bocchi V. Castagnetta

1986-01-01

361

Heat leak measurements facility  

SciTech Connect

Heat leak measurements of superconducting magnet suspension systems, and multilayer insulation (MLI) systems are important for the optimum design of magnet cryostats. For this purpose, a cryogenic test facility was developed having a versatile functional end in which test components of differing geometrical configurations can be installed and evaluated. This paper details the test facility design and operating parameters. Experimental results of heat leak measurements to 4.5 K obtained on a post type support system having heat intercepts at 10 K and 80 K are presented. Included are measurements obtained while operating the 10 K intercept at temperatures above 10 K, i.e., in the 10-40 K range. Also reported is a description of the test facility conversion for a heat load study of several MLI systems with variations of MLI installation technique. The results of the first MLI system tested are presented.

Gonczy, J.D.; Kuchnir, M.; Nicol, T.H.; Niemann, R.C.; Powers, R.J.

1985-09-01

362

Hurricanes as Heat Engines  

NSDL National Science Digital Library

In this activity, students examine the effects of hurricanes on sea surface temperature using NASA data. They examine authentic sea surface temperature data to explore how hurricanes extract heat energy from the ocean surface.

Data, My N.; Nasa

363

Solar energy: Packing heat  

NASA Astrophysics Data System (ADS)

Nanoscopic templates functionalized with light-reactive chromophores could ultimately be used to store solar energy and later release it as heat. Now, it has been shown that packing the chromophores together increases both storage capacity and lifetime.

Neale, Nathan R.

2014-05-01

364

Heat pipe manufacturing study  

NASA Technical Reports Server (NTRS)

Heat pipe manufacturing methods are examined with the goal of establishing cost effective procedures that will ultimately result in cheaper more reliable heat pipes. Those methods which are commonly used by all heat pipe manufacturers have been considered, including: (1) envelope and wick cleaning, (2) end closure and welding, (3) mechanical verification, (4) evacuation and charging, (5) working fluid purity, and (6) charge tube pinch off. The study is limited to moderate temperature aluminum and stainless steel heat pipes with ammonia, Freon-21 and methanol working fluids. Review and evaluation of available manufacturers techniques and procedures together with the results of specific manufacturing oriented tests have yielded a set of recommended cost-effective specifications which can be used by all manufacturers.

Edelstein, F.

1974-01-01

365

Solar-Heated Gasifier  

NASA Technical Reports Server (NTRS)

Catalytic coal and biomass gasifer system heated by solar energy. Sunlight from solar concentrator focused through quartz window onto ceramic-honeycomb absorber surface, which raises temperature of reactant steam, fluidizing gas, and reactor walls.

Qader, S. A.

1985-01-01

366

Heat Stability in Fluorosilicones.  

National Technical Information Service (NTIS)

Fluorosilicones are less heat stable than conventional silicones because (a) they are more likely to revert to low molecular weight cyclic products and (b) they are more susceptible to oxidation. Reversion is promoted by base catalyst residues from the po...

D. K. Thomas

1968-01-01

367

Composite heat damage assessment  

SciTech Connect

The effects of heat damage were determined on the residual mechanical, physical, and chemical properties of IM6/3501-6 laminates, and potential nondestructive techniques to detect and assess material heat damage were evaluated. About one thousand preconditioned specimens were exposed to elevated temperatures, then cooled to room temperature and tested in compression, flexure, interlaminar shear, shore-D hardness, weight loss, and change in thickness. Specimens experienced significant and irreversible reduction in their residual properties when exposed to temperatures exceeding the material upper service temperature of this material (350{degrees}F). The Diffuse Reflectance Infrared Fourier Transform and Laser-Pumped Fluorescence techniques were found to be capable of rapid, in-service, nondestructive detection and quantitation of heat damage in IM6/3501- 6. These techniques also have the potential applicability to detect and assess heat damage effects in other polymer matrix composites.

Janke, C.J.; Wachter, E.A. [Oak Ridge National Lab., TN (United States); Philpot, H.E. [Oak Ridge K-25 Site, TN (United States); Powell, G.L. [Oak Ridge Y-12 Plant, TN (United States)

1993-12-31

368

Investment casting heat transfer  

NSDL National Science Digital Library

Calculate temperature profile and Biot number in mixed conduction and convection/radiation heat transfer from liquid metal through a ceramic mold to the environment, and suggest a design change to reduce the probability of shattering due to thermal stress.

Powell, Adam C., IV

2004-12-15

369

Light vs. Heat Bulbs  

NSDL National Science Digital Library

Students measure the light output and temperature (as a measure of heat output) for three types of light bulbs to identify why some light bulbs are more efficient (more light with less energy) than others.

Office Of Educational Partnerships

370

Climate Wisconsin: Extreme Heat  

NSDL National Science Digital Library

This short video addresses the effects of heat waves on human populations, with African American residents of Milwaukee, Wisconsin, as the visual subjects. The narrative is done by a young spoken- word artist.

Board, Wisconsin E.; Wisconsin, Climate

371

Heating steels in vacuum  

SciTech Connect

It is recommended that high-strength and corrosion-resistant steels be heated in an electric vacuum furnace. Absence of oxidation and decarburization, decrease in the deformation of the part, increase in service life, plus safety, and nontoxicity in the shop, are cited as advantages. Annealing, carburizing, hardening, brazing, and sintering--all detailed-can be more efficiently accomplished in vacuum heating. As vacuum heating requires certain surface conditions, the compositions of residual mediums is studied. The microrelief and surface finish obtained after vacuum heating is determined. Annealing in a vacuum is compared to annealing in air, a depletion in manganese indicating a greater savings by use of vacuum. Ductility is also tested. The gas of special purity nitrogen is recommended for best results. In general, then, use of electric vacuum furnaces is recommended.

Marmer, E.N.

1983-03-01

372

Heat Reflecting Window Coatings.  

National Technical Information Service (NTIS)

Heat loss caused by radiation through the window glass is significantly reduced by the use of coatings that reflect infrared radiation but are transparent to the visible light. This selectivity can be achieved by using metallic films with sufficiently low...

E. Koskiahde

1986-01-01

373

Methane heat transfer investigation  

NASA Technical Reports Server (NTRS)

Future high chamber pressure LOX/hydrocarbon booster engines require copper-base alloy main combustion chamber coolant channels similar to the SSME to provide adequate cooling and resuable engine life. Therefore, it is of vital importance to evaluate the heat transfer characteristics and coking thresholds for LNG (94% methane) cooling, with a copper-base alloy material adjacent to the fuel coolant. High-pressure methane cooling and coking characteristics were recently evaluated using stainless-steel heated tubes at methane bulk temperatures and coolant wall temperatures typical of advanced engine operation except at lower heat fluxes as limited by the tube material. As expected, there was no coking observed. However, coking evaluations need be conducted with a copper-base surface exposed to the methane coolant at higher heat fluxes approaching those of future high chamber pressure engines.

Cook, R. T.

1984-01-01

374

Methane heat transfer investigation  

NASA Technical Reports Server (NTRS)

Future high chamber pressure LOX/hydrocarbon booster engines require copper base alloy main combustion chamber coolant channels similar to the SSME to provide adequate cooling and reusable engine life. Therefore, it is of vital importance to evaluate the heat transfer characteristics and coking thresholds for LNG (94% methane) cooling, with a copper base alloy material adjacent to he fuel coolant. High pressure methane cooling and coking characteristics recently evaluated at Rocketdyne using stainless steel heated tubes at methane bulk temperatures and coolant wall temperatures typical of advanced engine operation except at lower heat fluxes as limited by the tube material. As expected, there was no coking observed. However, coking evaluations need be conducted with a copper base surface exposed to the methane coolant at higher heat fluxes approaching those of future high chamber pressure engines.

1984-01-01

375

Graphite-Fiber Heat Radiators  

NASA Technical Reports Server (NTRS)

Heat radiators of proposed type feature thermally conductive fibers protruding from metallic surfaces to provide increased heat-dissipation surface areas. Free of leaks and more reliable than radiators incorporating heat pipes. Also lightweight and relatively inexpensive. Radial graphite fibers carry heat away from spherical shell and radiate heat into space. Radiators prove useful on Earth in special industrial and scientific applications involving dissipation of heat in vacuum or in relatively still air.

Phillips, Wayne M.

1995-01-01

376

Mechanisms of coronal heating  

Microsoft Academic Search

The Sun is a mysterious star. The high temperature of the chromosphere and corona present one of the most puzzling problems\\u000a of solar physics. Observations show that the solar coronal heating problem is highly complex with many different facts. It\\u000a is likely that different heating mechanisms are at work in solar corona. Recent observations show that Magnetic Carpet is\\u000a a

S. R. Verma

2006-01-01

377

Microtube Strip Heat Exchanger  

SciTech Connect

Doty Scientific (DSI) believes their Microtube-Strip Heat Exchanger will contribute significantly to (a) the closed Brayton cycles being pursued at MIT, NASA, and elsewhere; (b) reverse Brayton cycle cryocoolers, currently being investigated by NASA for space missions, being applied to MRI superconducting magnets; and (c) high-efficiency cryogenic gas separation schemes for CO{sub 2} removal from exhaust stacks. The goal of this current study is to show the potential for substantial progress in high-effectiveness, low-cost, gas-to-gas heat exchangers for diverse applications at temperatures from below 100 K to above 1000 K. To date, the highest effectiveness measured is about 98%, and relative pressure drops below 0.1% with a specific conductance of about 45 W/kgK are reported. During the pre-award period DSI built and tested a 3-module heat exchanger bank using 103-tube microtube strip (MTS) modules. To add to their analytical capabilities, DSI has acquired computational fluid dynamics (CFD) software. This report describes the pre-award work and the status of the ten tasks of the current project, which are: analyze flow distribution and thermal stresses within individual modules; design a heat exchanger bank of ten modules with 400 microtube per module; obtain production quality tubestrip die and AISI 304 tubestrips; obtain production quality microtubing; construct revised MTS heat exchanger; construct dies and fixtures for prototype heat exchanger; construct 100 MTS modules; assemble 8-10 prototype MTS heat exchangers; test prototype MTS heat exchanger; and verify test through independent means. 7 refs., 9 figs. 1 tab. (CK)

Doty, F.D.

1990-12-27

378

Geo-heat center  

SciTech Connect

A summary is presented of the Geo-Heat Center from its origin in 1974. The GHC has been involved in a number of studies and projects. A few of these are: construction of a greenhouse based on geothermal applications, an aquaculture project raising freshwater Malaysian prawns, an investigation of ground water characteristics and corrosion problems associated with the use of geothermal waters, and the assessment of the potential utilization of direct-heat applications of geothermal energy for an agribusiness.

Lienau, P.J.; Fornes, A.O.

1983-01-01

379

Heat Pipe Systems  

NASA Astrophysics Data System (ADS)

Solar Fundamentals, Inc.'s hot water system employs space-derived heat pipe technology. It is used by a meat packing plant to heat water for cleaning processing machinery. Unit is complete system with water heater, hot water storage, electrical controls and auxiliary components. Other than fans and a circulating pump, there are no moving parts. System's unique design eliminates problems of balancing, leaking, corroding, and freezing.

1988-01-01

380

Heat transfer wall  

US Patent & Trademark Office Database

In a perforated heat conductive surface structure having voids under an outer surface and openings in the outer surface, in order to obtain a high performance in particular at a low pressure and low temperature region, there is provided a heat transfer wall in which a thickness of a wall at a ceiling of each void and a length of a passage of the respective openings are increased in predetermined ranges.

1986-08-19

381

Solar heat transport fluid  

NASA Technical Reports Server (NTRS)

The progress made on the development and delivery of noncorrosive fluid subsystems is reported. These subsystems are to be compatible with closed-loop solar heating or combined heating and hot water systems. They are also to be compatible with both metallic and non-metallic plumbing systems. At least 100 gallons of each type of fluid recommended by the contractor will be delivered under the contract. The performance testing of a number of fluids is described.

1978-01-01

382

Nonequilibrium heat capacity.  

PubMed

Development of steady state thermodynamics and statistical mechanics depends crucially on our ability to extend the notions of equilibrium thermodynamics to nonequilibrium steady states (NESS). The present paper considers the extension of heat capacity. A modified definition is proposed which continues to maintain the same relation to steady state Shannon entropy as in equilibrium, thus providing a thermodynamically consistent treatment of NESS heat capacity. PMID:24483414

Mandal, Dibyendu

2013-12-01

383

Freezable heat pipe  

DOEpatents

A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

Ernst, Donald M. (Leola, PA); Sanzi, James L. (Lancaster, PA)

1981-02-03

384

Heat flux limiting sleeves  

DOEpatents

A heat limiting tubular sleeve extending over only a portion of a tube having a generally uniform outside diameter, the sleeve being open on both ends, having one end thereof larger in diameter than the other end thereof and having a wall thickness which decreases in the same direction as the diameter of the sleeve decreases so that the heat transfer through the sleeve and tube is less adjacent the large diameter end of the sleeve than adjacent the other end thereof.

Harris, William G. (Tampa, FL)

1985-01-01

385

Integration of Thermoelectric Generators and Wood Stove to Produce Heat, Hot Water, and Electrical Power  

NASA Astrophysics Data System (ADS)

Traditional fire stoves are characterized by low efficiency. In this experimental study, the combustion chamber of the stove is augmented by two devices. An electric fan can increase the air-to-fuel ratio in order to increase the system's efficiency and decrease air pollution by providing complete combustion of wood. In addition, thermoelectric generators (TEGs) produce power that can be used to satisfy all basic needs. In this study, a water-based cooling system is designed to increase the efficiency of the TEGs and also produce hot water for residential use. Through a range of tests, an average of 7.9 W was achieved by a commercial TEG with substrate area of 56 mm × 56 mm, which can produce 14.7 W output power at the maximum matched load. The total power generated by the stove is 166 W. Also, in this study a reasonable ratio of fuel to time is described for residential use. The presented prototype is designed to fulfill the basic needs of domestic electricity, hot water, and essential heat for warming the room and cooking.

Goudarzi, A. M.; Mazandarani, P.; Panahi, R.; Behsaz, H.; Rezania, A.; Rosendahl, L. A.

2013-07-01

386

Magnetic heat pump design  

NASA Astrophysics Data System (ADS)

Heat pumps utilizing the magnetocaloric effect offer a potentially attractive alternative to conventional heat pumps and refrigerators. Many physical configurations of magnetic heat pumps are possible. Major classes include those requiring electrical energy input and those with mechanical energy input. Mechanical energy is used to move magnets, working material, or magnetic shielding. Each type of mechanical magnetic heat pump can be built in a rotary (recuperative) or reciprocal (regenerative) configuration. Machines with electrical energy input utilize modulation of the magnetic field to cause working material to execute the desired thermodynamic cycle, and can also be recuperative or regenerative. Recuperative rotary heat pumps in which working material is moved past stationary magnets is the preferred configuration. Regenerative devices suffer performance degradation from temperature change of regenerator material and mixing and conduction in the regenerator. Field modulated cycles are not practical due to ac losses in superconducting magnets. Development of methods for recuperator fluid pumping is the major challenge in design of rotary recuperative devices. Several pumping options are presented, and the design of a bench scale heat pump described.

Kirol, L. D.; Dacus, M. W.

1988-03-01

387

Conducting the Heat  

NASA Technical Reports Server (NTRS)

Heat conduction plays an important role in the efficiency and life span of electronic components. To keep electronic components running efficiently and at a proper temperature, thermal management systems transfer heat generated from the components to thermal surfaces such as heat sinks, heat pipes, radiators, or heat spreaders. Thermal surfaces absorb the heat from the electrical components and dissipate it into the environment, preventing overheating. To ensure the best contact between electrical components and thermal surfaces, thermal interface materials are applied. In addition to having high conductivity, ideal thermal interface materials should be compliant to conform to the components, increasing the surface contact. While many different types of interface materials exist for varying purposes, Energy Science Laboratories, Inc. (ESLI), of San Diego, California, proposed using carbon velvets as thermal interface materials for general aerospace and electronics applications. NASA s Johnson Space Center granted ESLI a Small Business Innovation Research (SBIR) contract to develop thermal interface materials that are lightweight and compliant, and demonstrate high thermal conductance even for nonflat surfaces. Through Phase II SBIR work, ESLI created Vel-Therm for the commercial market. Vel-Therm is a soft, carbon fiber velvet consisting of numerous high thermal conductivity carbon fibers anchored in a thin layer of adhesive. The velvets are fabricated by precision cutting continuous carbon fiber tows and electrostatically flocking the fibers into uncured adhesive, using proprietary techniques.

2003-01-01

388

Convective heat flow probe  

DOEpatents

A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

Dunn, J.C.; Hardee, H.C.; Striker, R.P.

1984-01-09

389

Chimney heat exchanger  

SciTech Connect

A heat exchanger for installation on the top of a chimney of a building includes a housing having a lower end receiving the top of the chimney and an upper end with openings permitting the escape of effluent from the chimney and a heat exchanger assembly disposed in the housing including a central chamber and a spirally arranged duct network defining an effluent spiral path between the top of the chimney and the central chamber and a fresh air spiral path between an inlet disposed at the lower end of the housing and the central chamber, the effluent and fresh air spiral paths being in heat exchange relationship such that air passing through the fresh air spiral path is heated by hot effluent gases passing upward through the chimney and the effluent spiral path for use in heating the building. A pollution trap can be disposed in the central chamber of the heat exchanger assembly for removing pollutants from the effluent, the pollution trap including a rotating cage carrying pumice stones for absorbing pollutants from the effluent with the surface of the pumice gradually ground off to reveal fresh stone as the cage rotates.

Whiteley, I.C.

1981-09-01

390

Protuberance heating test program  

NASA Technical Reports Server (NTRS)

Results are presented of the protuberance heating test program. Four general protuberance shapes on a flat plate were tested. Presentation and evaluation of the data both on the protuberance and in the wake regions are made. The test program is an extension of the general protuberance heat transfer test. The additional series of tests was conducted to define the extent of wake heating and to assess the effects of Reynolds number variation on heating both on and around the protuberances. The protuberance models were mounted near the forward end of a six-foot instrumented test plate with stringers that simulated interstage and skirt structure of the Saturn S-4B stage. The tests were performed at Mach numbers of 2.49, 3.51, and 4.44. Reynolds numbers per foot of 3 million and 1.5 million were used for the two lower Mach numbers and 3 million for a Mach number of 4.44. The test Mach numbers simulated the Saturn S-4B flight conditions during the most severe aerodynamic heating period. The test Reynolds numbers were somewhat higher than the flight values, but lower values could not be used because of tunnel and instrumentation limitations. Oil flow runs were made on two representative models at various combinations of Mach number and Reynolds number to help define the extent of wake heating.

Sieker, W. D.

1966-01-01

391

Radial flow heat exchanger  

DOEpatents

A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

Valenzuela, Javier (Hanover, NH)

2001-01-01

392

Intrinsically irreversible heat engine  

DOEpatents

A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

Wheatley, J.C.; Swift, G.W.; Migliori, A.

1984-01-01

393

Solar liquid heating system  

SciTech Connect

A solar liquid heating system has a collector receiving solar energy and heating a liquid. A liquid transfer pump moves the heated liquid to a heat transfer tank which heats water. The collector has a plate assembly mounted on a frame. Heat insulated bottoms, sides, and ends surrounded by the frame form an elongated chamber accommodating the plate assembly. The plate assembly has a plurality of side-by-side longitudinal plates. Adjacent plates have generally c-shaped sections that are located about a longitudinal tube for carrying liquid. Adjacent plates have lip and hook inter-connecting structures that cooperate with each other to clamp the tube between the c-shaped sections of the plates. The opposite ends of the tubes are connected to transverse tubular headers. The headers project through resilient grommets mounted on the sides of the frame. The top sides of the plate assembly are coated with black solar energy absorbing material. A light transparent cover encloses the plate assembly within the chamber of the collector.

Harder, W.J.; Pickett, J.M.

1982-07-13

394

Improved Thin, Flexible Heat Pipes  

NASA Technical Reports Server (NTRS)

Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

2004-01-01

395

Inductive Electron Heating Revisited  

NASA Astrophysics Data System (ADS)

Inductively Coupled Plasmas (ICPs) have been studied for over a century. Recently, ICPs have been rediscovered by the multi-billion dollar semiconductor industry as an important class of high-density, low-pressure plasma sources suitable for the manufacture of next-generation integrated circuits. Present low-pressure ICP development is among the most active areas of plasma research. However, this development remains largely empirical, a prohibitively expensive approach for upcoming 300-mm diameter wafers. Hence, there is an urgent need for basic ICP plasma physics research, including experimental characterization and predictive numerical modeling. Inductive radio frequency (rf) power absorption is fundamental to the ICP electron heating and the resulting plasma transport but remains poorly understood. For example, recent experimental measurements and supporting fluid calculationsfootnote M. Tuszewski, Phys. Rev. Lett. 77 in press (1996) on a commercial deposition tool prototype show that the induced rf magnetic fields in the source can cause an order of magnitude reduction in plasma conductivity and in electron heating power density. In some cases, the rf fields penetrate through the entire volume of the ICP discharges while existing models that neglect the induced rf magnetic fields predict rf absorption in a thin skin layer near the plasma surface. The rf magnetic fields also cause more subtle changes in the plasma density and in the electron temperature spatial distributions. These data will be presented and the role of basic research in the applied world of semiconductor manufacturing will be discussed. ^*This research was conducted under the auspices of the U.S. DOE, supported by funds provided by the University of California for discretionary research by Los Alamos National Laboratory.

Tuszewski, M.

1996-11-01

396

Low-cost process-heat recovery  

NASA Astrophysics Data System (ADS)

Heat recovery systems developed specifically for use with gas-fired ovens such as those used in restaurants and bakeries are found to be a viable energy saying option for reducing operating expenses. The objectives of the work are: to assess waste heat recovery potential, perform and economic analysis, design heat exchanger and system, develop an integrated computer program. The first three objectives were successfully met for flat plate and plate fin air to air heat recovery systems. An interactive computer program is developed for heat recovery systems using the FORTRAN language, and an economic analysis program is developed.

Theisen, P.; McCray, J.

1982-05-01

397

Chord integrated neutral particle diagnostic data analysis for neutral beam injection and ion cyclotron radio frequency heated plasma in a complex Large Helical Device geometry  

SciTech Connect

Energy and angle-resolved measurements of charge exchange neutral particle fluxes from the plasma provide information about T{sub i}, as well as non-Maxwellian substantially anisotropic ion distribution tails due to neutral beam injection (NBI) and ion cyclotron radio frequency (ICRF) heating. The measured chord integral neutral flux calculation scheme for the Large Helical Device magnetic surface geometry is given. Calculation results are shown for measurable atomic energy spectra corresponding to heating-induced fast ion distributions from simplified Fokker-Planck models. The behavior of calculated and experimental suprathermal particle distributions from NBI and ICRF heated plasma is discussed in the context of the experimental data interpretation.

Veshchev, E. A.; Goncharov, P. R.; Ozaki, T.; Sudo, S.; Lyon, J. F. [Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193 (Japan); National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)

2006-10-15

398

Chord integrated neutral particle diagnostic data analysis for neutral beam injection and ion cyclotron radio frequency heated plasma in a complex Large Helical Device geometry  

NASA Astrophysics Data System (ADS)

Energy and angle-resolved measurements of charge exchange neutral particle fluxes from the plasma provide information about Ti, as well as non-Maxwellian substantially anisotropic ion distribution tails due to neutral beam injection (NBI) and ion cyclotron radio frequency (ICRF) heating. The measured chord integral neutral flux calculation scheme for the Large Helical Device magnetic surface geometry is given. Calculation results are shown for measurable atomic energy spectra corresponding to heating-induced fast ion distributions from simplified Fokker-Planck models. The behavior of calculated and experimental suprathermal particle distributions from NBI and ICRF heated plasma is discussed in the context of the experimental data interpretation.

Veshchev, E. A.; Goncharov, P. R.; Ozaki, T.; Sudo, S.; Lyon, J. F.

2006-10-01

399

Integration of LHCD and IBW heating for high-performance discharges under steady-state operation in the HT7 tokamak  

Microsoft Academic Search

Significant progress in obtaining high-performance discharges under quasi-steady-states in the HT-7 superconducting tokamak has been realized since the last IAEA meeting. In relation to the previous experiments, various features of the non-inductive current driven, heating, profile control, MHD stabilization and edge physics are integrated and optimized to achieve steady-state high-performance discharges. Both on-axis and off-axis electron heating with global peaked

Baonian Wan; Jiangang Li

2003-01-01

400

Measurement of unsteady heat flux  

NASA Astrophysics Data System (ADS)

The authors examine the influence of the volume nature of absorption of radiative flux on the operation of a heat converter with a thin-film resistive sensor. It is shown that allowing for volume absorption leads to a change in the form of the transfer function: it becomes rational (in contrast with the case of surface absorption, where the transfer function is irrational), because the converter heat-sensitive element 'integrates' the incident flux. The influence of the inertial properties of thin layers of black coating on the response time of the converter is examined.

Bautin, A. V.; Poliakov, Iu. A.

1980-07-01

401

Utilization of heat pipes for transfer heat from the flue gas into the heat transfer medium  

NASA Astrophysics Data System (ADS)

The contribution is listed possible application of heat pipes in systems for obtaining heat from flue gas of small heat sources. It is also stated in the contribution design an experimental device on which to study the impact of fill (the quantity, type of load) at various temperature parameters (temperature heating and cooling) thermal power transferred to the heat pipe. Is listed measurement methodology using heat pipes designed experimental facility, measurement results and analysis of the results obtained.

Lenhard, Richard; Kaduchová, Katarína; Papu?ík, Štefan; Janda?ka, Jozef

2014-03-01

402

Air circuit with heating pump  

NASA Astrophysics Data System (ADS)

A pump which draws energy from exhaust air from a paper drying process to heat up the blow air was studied. The use of a heat pump instead of a steam heated exchanger can reduce primary energy consumption for blown air heating by more than half and the costs for air heating up to half. The amortization times for the heat pump extend from 5 to 10 years. Since in the pulp and paper industry, amortization times of less than two years are required for such relatively small investments, the heat pump so far is only used to heat blown air under highly favorable conditions. The rising energy prices shorten the heat pump amortization time. The 100% fuel price increase brought the heat pump with diesel engine drive already to very favorable amortization times of 2 to 5 years. A 20% increase will make the heat pump economically advantageous with an amortization time between 1 and 2 years.

Holik, H.; Bauder, H. J.; Brugger, H.; Reinhart, A.; Spott, K. H.

1980-12-01

403

Moist Heat or Dry Heat for Delayed Onset Muscle Soreness  

PubMed Central

Background Heat is commonly used in physical therapy following exercise induced delayed onset muscle soreness (DOMS). Most heat modalities used in a clinical setting for DOMS are only applied for 5 to 20 minutes. This minimal heat exposure causes little, if any, change in deep tissue temperature. For this reason, long duration dry chemical heat packs are used at home to slowly and safely warm tissue and reduce potential heat damage while reducing pain associated from DOMS. Clinically, it has been shown that moist heat penetrates deep tissue faster than dry heat. Therefore, in home use chemical moist heat may be more efficacious than dry heat to provide pain relief and reduce tissue damage following exercise DOMS. However, chemical moist heat only lasts for 2 hours compared to the 8 hours duration of chemical dry heat packs. The purpose of this study was to compare the beneficial effect of dry heat versus moist heat on 100 young subjects after exercise induce DOMS. Methods One hundred subjects exercised for 15 minutes accomplishing squats. Before and for 3 days after, strength, muscle soreness, tissue resistance, and the force to passively move the knee were recorded. Heat and moist heat were applied in different groups either immediately after exercise or 24 hours later. Results The research results of this study showed that immediate application of heat, either dry (8 hours application) or moist (2 hours application), had a similar preservation of quadriceps muscle strength and muscle activity. Results also revealed that the greatest pain reduction was shown after immediate application of moist heat. Never the less, immediate application of dry heat had a similar effect but to a lesser extent. Conclusion It should be noted that moist heat had not only similar benefits of dry heat but in some cases enhanced benefits, and with only 25% of the time of application of the dry heat.

Petrofsky, Jerrold; Berk, Lee; Bains, Gurinder; Khowailed, Iman Akef; Hui, Timothy; Granado, Michael; Laymon, Mike; Lee, Haneul

2013-01-01

404

Heat-pump-centered Integrated Community Energy Systems: systems development, Consolidated Natural Gas Service Company. Final report  

SciTech Connect

The Heat-Actuated Heat Pump Centered Integrated Community Energy System (HAHP-ICES) utilizes a gas-fired, engine-driven, heat pump and commercial buildings, and offers several advantages over the more conventional equipment it is intended to supplant. The general non-site-specific application assumes a hypothetical community of one 59,000 ft/sup 2/ office building and five 24-unit, low-rise apartment buildings located in a region with a climate similar to Chicago. This community serves as a starting point - the base case - upon which various sensitivity analyses are performed and through which the performance characteristics of the HAHP are explored. The results of these analyses provided the selection criteria for the site-specific application of the HAHP-ICES concept to a real-world community. The site-specific community consists of 42 townhouses; five 120-unit, low-rise apartment buildings; five 104-unit high-rise apartment buildings; one 124,000 ft/sup 2/ office building; and a single 135,000 ft/sup 2/ retail building located in Monroeville, Pa. The base-case analyses confirmed that the HAHP-ICES has significant potentials for reducing the primary energy consumption and pollutant emissions associated with space conditioning when compared with a conventional system. Primary energy consumption was reduced by 30%, while emission reductions ranged from 39 to 77%. The results of the site-specific analysis indicate that reductions in energy consumption of between 15 and 22% are possible when a HAHP-ICES is selected as opposed to conventional HVAC equipment.

Baker, N.R.; Donakowski, T.D.; Foster, R.B.; Sala, D.L.; Tison, R.R.; Whaley, T.P.; Yudow, B.D.; Swenson, P.F.

1980-01-01

405

Passive thermosyphon solar heating and cooling module with supplementary heating  

NASA Technical Reports Server (NTRS)

A collection of three quarterly reports from Sigma Research, Inc., covering progress and status from January through September 1977 are presented. Three heat exchangers are developed for use in a solar heating and cooling system for installation into single-family dwellings. Each exchanger consists of one heating and cooling module and one submerged electric water heating element.

1977-01-01

406

Heat-transfer coefficients in agitated vessels. Latent heat models  

Microsoft Academic Search

Latent heat models were developed to calculate heat-transfer coefficients in agitated vessels for two cases: (1) heating with a condensable fluid flowing through coils and jackets; (2) vacuum reflux cooling with an overhead condenser. In either case the mathematical treatment, based on macroscopic balances, requires no iterative schemes. In addition to providing heat-transfer coefficients, the models predict flow rates of

Enio Kumpinsky

1996-01-01

407

Heat exchanger device and method for heat removal or transfer  

DOEpatents

Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

Koplow, Jeffrey P

2013-12-10

408

The heat pipe - A simple, versatile, efficient heat transfer tool  

NASA Technical Reports Server (NTRS)

Heat pipe transports large quantities of heat from source to sink with only small temperature drop. Thermal energy is transferred to and from heat pipe by any combination of conduction, convection, or radiation heat transfer. Pipes transport energy from open flames, nuclear sources, and electronic equipment.

Schwartz, J.

1971-01-01

409

Economic Analysis of Heating Systems using Geothermal Heat Pump  

Microsoft Academic Search

This paper presents profitability evaluation of geothermal heat pumps as an alternative, non-polluting solution for heating of modern buildings and well-insulated houses. The investment into geothermal heat pump is much higher than for heating stations with fossil fuels, more than four times as for earth gas and more than three times than for light fuel oil, but the operating costs

E. TORHAC; L. C. LIPUS; J. KROPE; D. GORICANEC; A. SALJNIKOV; R. STIPIC; Ð. KOZIC

410

Heat exchanger device and method for heat removal or transfer  

DOEpatents

Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

Koplow, Jeffrey P. (San Ramon, CA)

2012-07-24

411

Integrating heat treatment, biocontrol and sodium bicarbonate to reduce postharvest decay of apple caused by Colletotrichum acutatum and Penicillium expansum  

Microsoft Academic Search

‘Golden Delicious’ apples were wound inoculated with conidial suspensions of either Colletotrichum acutatum or Penicillium expansum, then treated with heat (38°C) for 4 days, sodium bicarbonate, and\\/or one of two heat tolerant biocontrol agents (yeasts). Following four months storage at 0°C, the apples were left at room temperature for two weeks. Populations of antagonists were stable throughout the experiment and

William S. Conway; Britta Leverentz; Wojciech J. Janisiewicz; Amy B. Blodgett; Robert A. Saftner; Mary J. Camp

2004-01-01

412

Enceladus' Enigmatic Heat Flow  

NASA Astrophysics Data System (ADS)

Accurate knowledge of Enceladus' heat flow is important because it provides a vital constraint on Enceladus' tidal dissipation mechanisms, orbital evolution, and the physical processes that generate the plumes. In 2011 we published an estimate of the current heat flow from Enceladus' active south polar terrain: 15.8 +/- 3.1 GW (Howett et al., 2011). This value was calculated by first estimating by modeling, and then removing, the passive component from 17 to 1000 micron observations made of the entire south polar terrain by Cassini's Composite Infrared Spectrometer (CIRS). The heat flow was then directly calculated from the residual, assumed endogenic, component. The derived heat flow of 15.8 GW was surprisingly high, about 10 times greater than that predicted by steady-state tidal heating (Meyer and Wisdom, 2007). CIRS has also returned high spatial resolution observations of Enceladus' active south polar terrain. Two separate observations are used: 9 to 16 micron observations taken over nearly the complete south polar terrain and a single 17 to 1000 micron scan over Damascus, Baghdad and Cairo. The shorter wavelength observations are only sensitive to high temperature emission (>70 K), and so longer wavelength observations are required (despite their limited spatial coverage) to estimate the low temperature emission from the stripes. Analysis of these higher resolution observations tells a different story of Enceladus' endogenic heat flow: the preliminary estimate of the heat flow from the active tiger stripes using these observations is 4.2 GW. An additional 0.5 GW must be added to this number to account for the latent heat release by the plumes (Ingersoll and Pankine 2009), giving a total preliminary estimate of 4.9 GW. The discrepancy in these two numbers is significant and we are currently investigating the cause. One possible reason is that there is significantly higher endogenic emission from the regions between the tiger stripes than we currently estimate (based on the comparison of the single long-wavelength scan across the fractures). It is also possible that the earlier modeling efforts underestimated Enceladus' passive emission, resulting in an overestimation of Enceladus' heat flow.

Howett, C.; Spencer, J. R.; Spencer, D.; Verbiscer, A.; Hurford, T.; Segura, M.

2013-12-01

413

High heat flux heat pipe mechanism for cooling of electronics  

Microsoft Academic Search

This paper discusses an advanced heat pipe mechanism that has the potential of achieving heat flux capabilities over 250 W\\/cm2. The mechanism utilizes thermally driven pulsating two-phase flow to achieve high heat flux capability and heat transfer coefficient. A simplified hydrodynamic model in was developed to guide the proof-of-concept heat pipe design. A more detailed numerical model was also developed

Z. Jon Zuo; M. T. North; K. L. Wert

2001-01-01

414

Solar heating system  

SciTech Connect

A solar heating system for a structure in which a matrix of beverage containers of the convenient opening variety is mounted on a generally flat support member. The beverage containers extend through holes in the support member formed from alternating polygons of a generally checkerboard surface design. A resilient plug seals the opening at one end of each container and a pair of collector tubes extend through the plug into the interior of each container. The collector tubes of adjacent containers are connected together such that all containers are connected in a series relationship. Those surface areas of the support member not occupied by the containers are contoured and have an outer surface appropriate to reflect heat and light toward the containers which themselves have a coating of a heat and light conductive substance. Fluid is pumped from a reservoir and through the containers under sunny conditions or may be diverted from the matrix during cloudy conditions or at night. In the latter events, an insulated canopy may be extended to cover the matrix. The amount of heat taken from the system to heat the structure may also be appropriately controlled.

Root, E.J.

1980-03-11

415

Conquer heat exchanger fouling  

SciTech Connect

Fouling plays a dominant role in heat exchanger performance. It is extremely important to choose the most appropriate type of heat exchanger for a particular application and adopt proper values for fouling resistance. A design practice for shell-and-tube heat exchangers that will limit fouling to a minimum and thus ensure trouble-free operation is essential. Due to the availability of specialized software, the thermal design of heat exchangers has become precise and scientific. The results occasionally have to be tempered with practical experience and engineering judgment, but generally these computer programs are very reliable and authentic. However, the above is true only for determining heat-transfer coefficients and pressure drop. One important area that cannot possibly be addressed by design software is fouling. While a proper selection of fouling resistance is extremely difficult due to the numerous factors involved, a sound design practice will minimize any errors. However, it is important to first understand the phenomenon of fouling. The paper describes what fouling is, types of fouling, factors affecting fouling, providing a fouling allowance, selecting a fouling resistance, and overcoming fouling through better design.

Mukherjee, R. [Engineers India Ltd., New Delhi (India)

1996-01-01

416

Environmental heating system  

SciTech Connect

A heating system for heating a building includes a solar energy collector. The collector is constructed from a plurality of glass panels. A first group of glass panels are mounted in an inverted pyramid with mirror surfaces to reflect solar energy to the base of the pyramid. A second group of transparent panels form an upright pyramid which is joined with the first pyramid at the base. A collector coil containing a circulating liquid is mounted at the junction of the bases of the two pyramids to collect solar energy which passes through the transparent upper pyramid and which is also reflected from the inverted pyramid. Water or other fluid is circulated through the collector coil and stored in an insulated storage tank. Thermostatic control is used to control the circulation of the heating fluid in accordance with the temperature. The heating fluid is pumped from the storage tank to various use devices such as baseboard radiators, water heaters and other devices which require heat.

Komula, R.W.

1984-01-31

417

Episodic Coronal Loop Heating  

NASA Astrophysics Data System (ADS)

Coronal loop temperatures are known to be of a few millions degrees but the nature of the energy source remains as a longstanding fundamental problem for solar (and stellar) physics. Observations of solar atmospheric plasma show clear evidence of frequent very localised heating events, which may be statistically responsible for heating of the solar upper atmosphere. One heating theory indicates that these micro-scale events are driven by localized magnetic field reconnection. In this paper, we present the results of numerical calculations that describe the response of the coronal plasma to small-scale heating pulses in a magnetic loop. In particular, we study the effects of energy input pulses injected randomly near the two footpoints of a semi-circular loop. We have found that increasing the elapsing time between successive pulses, the overall loop temperature decreases. When a critical elapsing time is reached the loop can no longer be maintained at typical coronal temperatures. These features have some support from SOHO-CDS observations of coronal loops which seem to undergo strong variability especially in active regions of the solar atmosphere (Kjeldseth-Moe &Brekke, 1998). We also have found that successive random pulses can statistically maintain the average plasma temperature at typical coronal values. Due to the randomness of the heat injections, the resulting temperature profiles show thermal bumps that could be connected to intermittent behaviour in the transition region and the low corona.

Mendoza-Briceño, C. A.; Erdélyi, R.

2004-01-01

418

Heat exchanger-accumulator  

DOEpatents

What is disclosed is a heat exchanger-accumulator for vaporizing a refrigerant or the like, characterized by an upright pressure vessel having a top, bottom and side walls; an inlet conduit eccentrically and sealingly penetrating through the top; a tubular overflow chamber disposed within the vessel and sealingly connected with the bottom so as to define an annular outer volumetric chamber for receiving refrigerant; a heat transfer coil disposed in the outer volumetric chamber for vaporizing the liquid refrigerant that accumulates there; the heat transfer coil defining a passageway for circulating an externally supplied heat exchange fluid; transferring heat efficiently from the fluid; and freely allowing vaporized refrigerant to escape upwardly from the liquid refrigerant; and a refrigerant discharge conduit penetrating sealingly through the top and traversing substantially the length of the pressurized vessel downwardly and upwardly such that its inlet is near the top of the pressurized vessel so as to provide a means for transporting refrigerant vapor from the vessel. The refrigerant discharge conduit has metering orifices, or passageways, penetrating laterally through its walls near the bottom, communicating respectively interiorly and exteriorly of the overflow chamber for controllably carrying small amounts of liquid refrigerant and oil to the effluent stream of refrigerant gas.

Ecker, Amir L. (Dallas, TX)

1980-01-01

419

Metal hydride heat pump  

NASA Astrophysics Data System (ADS)

The materials, design features, and projected performance of a metal hydride heat pump are explored. Two alloys with hydrogen absorption/desorption (endothermic) properties are included, with the hydrogen being driven back and forth between the two and not consumed. Heat rejected by absorption is rejected by the cold side to the air. When the cold side is full, the pressure differential is reversed and the hydrogen returns to the warm section. Heat in a coolant is used at the cold side to initiate dissociation from the hydride. A test unit providing 3.5.7 kWt of cooling capacity with a source temperature of 200 F and a refrigerated cycle of 40-50 F was built using LaNi5 for the warm side and MMNi4.5FeO.85 on the cold side. Full power was reached in 3-6 min and performance coefficients near .5 were attained. Waste heat, solar and fossil fuel heat sources were identified as viable power supply candidates for refrigeration units requiring 0.5-10.0 tons of capacity.

Rohy, D. A.; Argabright, T. A.; Wade, G. W.

420

Fault-Tolerant Heat Exchanger  

NASA Technical Reports Server (NTRS)

A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

Izenson, Michael G.; Crowley, Christopher J.

2005-01-01

421

Liquid/liquid heat exchanger  

NASA Technical Reports Server (NTRS)

Conceptual design for heat exchanger, utilizing two immiscible liquids with dissimilar specific gravities in direct contact, is more efficient mechanism of heat transfer than conventional heat exchangers with walls or membranes. Concept could be adapted for collection of heat from solar or geothermal sources.

Miller, C. G.

1980-01-01

422

Physical principles of heat pipes  

Microsoft Academic Search

Heat pipes are used whenever high rates of heat transfer or the control or conversion of heat flows are required. This book covers the physical principles of operation of heat pipes and choice of working fluid related to temperature range. The authors demonstrate how performance is limited by capillary pumping action in the wick together with impedance to liquid and

M. N. Ivanovskii; V. P. Sorokin; I. V. Yagodkin

1982-01-01

423

Experiments Demonstrate Geothermal Heating Process  

ERIC Educational Resources Information Center

When engineers design heat-pump-based geothermal heating systems for homes and other buildings, they can use coil loops buried around the perimeter of the structure to gather low-grade heat from the earth. As an alternative approach, they can drill well casings and store the summer's heat deep in the earth, then bring it back in the winter to warm…

Roman, Harry T.

2012-01-01

424

Deployable heat-pipe radiator  

NASA Technical Reports Server (NTRS)

Loop temperatures are controlled effectively under varying load conditions. Radiator has four separate pieces of hardware: heat-pipe panel, flexible heat-pipe leader, heat exchanger, fluid header. Single-fluid transport capacities of about 850 watts, corresponding to 51,000 watt-inches, have been achieved in 90 degree bend orientation of heat-pipe header.

Edelstein, F.

1978-01-01

425

Solar water heating in Pennsylvania  

Microsoft Academic Search

The most common application of solar energy in Pennsylvania is to heat water. Thousands of solar water heaters have been installed across the state. Solar water heating systems are an excellent application of solar energy because hot water is needed year-round. Water heating is usually the second highest energy need, after space heating, in homes. For a family of four,

M. B. Sheffer; Lau A. S

2009-01-01

426

Heat transfer in turbulent flow  

Microsoft Academic Search

The present volume on heat transfer in turbulent flow discusses heat transfer through a pressure-driven 3D boundary layer, the effects of simulated combustor turbulence on boundary layer heat transfer, an experiment on spatial and temporal turbulent structures of a natural convection boundary layer, and the influence of high mainstream turbulence on leading edge heat transfer. Attention is given to turbulent

R. S. Amano; M. E. Crawford; N. K. Anand

1990-01-01

427

Heat illness. I. Epidemiology.  

PubMed

Reliable information on the epidemiology of heat illness has come, until recently, mainly from the armed forces and, to a lesser extent, from some industries and civil communities. Data from the records of the British Army, Royal Navy, Royal Air Force, Indian Armed Forces, U.S. Army and forces engaged in the Arab-Israeli wars, from the South African gold mining corporations and Persian Gulf oil tankers, and from civilian communities, mainly in the U.S.A., are reviewed and discussed with particular reference to the classification of heat illness and definition of the terms used, and the effects on acclimatized and non-acclimatized personnel and on other sections of the civilian communities most at risk, i.e. the old and very young. This section concludes with an outline of the classification of acute heat illnesses from 1899 to the eighth revision of the WHO International Classification of Diseases in 1967. PMID:320723

Ellis, F P

1976-01-01

428

Shape memory heat engines  

NASA Astrophysics Data System (ADS)

The mechanical shape memory effect associated with a thermoelastic martensitic transformation can be used to convert heat directly into mechanical work. Laboratory simulation of two types of heat engine cycles (Stirling and Ericsson) has been performed to measure the amount of work available/cycle in a Ni-45 at. pct Ti alloy. Tensile deformations at ambient temperature induced martensite, while a subsequent increase in temperature caused a reversion to the parent phase during which a load was carried through the strain recovery (i.e., work was accomplished). The amount of heat necessary to carry the engines through a cycle was estimated from calorimeter measurements and the work performed/cycle. The measured efficiency of the system tested reached a maximum of 1.4 percent, which was well below the theoretical (Carnot) maximum efficiency of 35.6 percent.

Salzbrenner, R.

1984-06-01

429

Solar heat collector assembly  

SciTech Connect

A solar heat collector assembly includes a cylindrical transparent tube having an open end portion hermetically sealed by the use of a sealant and being held in vacuum state and a heat-collecting pipe secured in the transparent tube with its end portion extending outside the transparent tube through the sealant. The sealant of a transparent material, for example, is bowl-shaped and the heat-collecting pipe is secured to pass through the center of the bowl-shaped sealant. The pipe and the sealant are bonded together through the use of a proper adhesive metal material. The outer periphery of the sealant is further bonded to the open end portion of the transparent tube. The adhesive metal material is typically 426 alloy.

Tonomura, T.; Katto, A.; Shimada, M.; Takeishi, K.

1983-11-08

430

Induction heating coupler  

NASA Technical Reports Server (NTRS)

An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardely beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to magnetic flux passing between the two ends of the pole piece.

Fox, Robert L. (inventor); Copeland, Carl E. (inventor); Swaim, Robert J. (inventor); Coultrip, Robert H. (inventor); Johnston, David F. (inventor); Phillips, W. Morris (inventor); Johnson, Samuel D. (inventor); Dinkins, James R. (inventor); Buckley, John D. (inventor)

1994-01-01

431

Laser-heated thruster  

NASA Technical Reports Server (NTRS)

The development of computer codes for the thrust chamber of a rocket of which the propellant gas is heated by a CW laser beam was investigated. The following results are presented: (1) simplified models of laser heated thrusters for approximate parametric studies and performance mapping; (3) computer programs for thrust chamber design; and (3) shock tube experiment to measure absorption coefficients. Two thrust chamber design programs are outlined: (1) for seeded hydrogen, with both low temperature and high temperature seeds, which absorbs the laser radiation continuously, starting at the inlet gas temperature; and (2) for hydrogen seeded with cesium, in which a laser supported combustion wave stands near the gas inlet, and heats the gas up to a temperature at which the gas can absorb the laser energy.

Kemp, N. H.; Krech, R. H.

1980-01-01

432

Microgravity condensing heat exchanger  

NASA Technical Reports Server (NTRS)

A heat exchanger having a plurality of heat exchanging aluminum fins with hydrophilic condensing surfaces which are stacked and clamped between two cold plates. The cold plates are aligned radially along a plane extending through the axis of a cylindrical duct and hold the stacked and clamped portions of the heat exchanging fins along the axis of the cylindrical duct. The fins extend outwardly from the clamped portions along approximately radial planes. The spacing between fins is symmetric about the cold plates, and are somewhat more closely spaced as the angle they make with the cold plates approaches 90.degree.. Passageways extend through the fins between vertex spaces which provide capillary storage and communicate with passageways formed in the stacked and clamped portions of the fins, which communicate with water drains connected to a pump externally to the duct. Water with no entrained air is drawn from the capillary spaces.

Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor); North, Andrew (Inventor); Weislogel, Mark M. (Inventor)

2011-01-01

433

Direct heating surface combustor  

NASA Technical Reports Server (NTRS)

The combustor utilizes a non-adiabatic flame to provide low-emission combustion for gas turbines. A fuel-air mixture is directed through a porous wall, the other side of which serves as a combustion surface. A radiant heat sink disposed adjacent to and spaced from the combustion surface controls the combustor flame temperature in order to prevent the formation of oxides of nitrogen. A secondary air flow cools the heat sink. Additionally, up to 100% of secondary air flow is mixed with the combustion products at the direct heating surface combustor to dilute such products thereby reducing exit temperature. However, if less than 100% secondary air is mixed to the combustor, the remainder may be added to the combustion products further downstream.

Beremand, D. G.; Shire, L. I.; Mroz, T. S. (inventors)

1978-01-01

434

Serpentine heat exchanger  

SciTech Connect

This patent describes a furnace having a burner means for providing hot products of combustion, and an air flow means for circulating conditioned air, a heat exchanger for transferring heat from products of combustion to conditioned air. The heat exchanger comprises first and second matched clamshell plates assembled together. The plates connected at their respective edges by a sealing means for providing a seal thereat, each the plate having an internal surface defining a depression. The depressions together defining a serpentine passageway, an entrance and exhaust ported formed in the passageway. The surfaces including elongated ribs for obstructing fluid flow adjacent the exhaust portal and for directing fluid flow to under-utilized portions in the passageway.

Tomlinson, R.S.

1991-01-08

435

Externally heated thermal battery  

NASA Astrophysics Data System (ADS)

A thermal battery activated by external heat comprising an anode (e.g., composed of a lithium-aluminum alloy), a cathode (e.g., composed of iron disulfide), and an electrolyte (e.g., a lithium chloride-potassium chloride eutectic) with the electrolyte inactive at ambient temperature but activated by melting at a predetermined temperature when exposed to external heating is presented. The battery can be used as a sensor or to ignite pyrotechnic and power electronic devices in a system for reducing the hazard of ordnance exposed to detrimental heating. A particular application is the use of the battery to activate a squib to function in conjunction with one or more other components to vent an ordnance case in order to prevent its explosion in a fire.

Pracchia, Louis; Vetter, Ronald F.; Rosenlof, Darwin

1991-04-01

436

3D CFD Electrochemical and Heat Transfer Model of an Integrated-Planar Solid Oxide Electrolysis Cells  

SciTech Connect

A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis cell performance and steam electrolysis in a new novel integrated planar porous-tube supported solid oxide electrolysis cell (SOEC). The model is of several integrated planar cells attached to a ceramic support tube. This design is being evaluated with modeling at the Idaho National Laboratory. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Mean per-cell area-specific-resistance (ASR) values decrease with increasing current density. Predicted mean outlet hydrogen and steam concentrations vary linearly with current density, as expected. Effects of variations in operating temperature, gas flow rate, cathode and anode exchange current density, and contact resistance from the base case are presented. Contour plots of local electrolyte temperature, current density, and Nernst potential indicated the effects of heat transfer, reaction cooling/heating, and change in local gas composition. Results are discussed for using this design in the electrolysis mode. Discussion of thermal neutral voltage, enthalpy of reaction, hydrogen production, cell thermal efficiency, cell electrical efficiency, and Gibbs free energy are discussed and reported herein.

Grant Hawkes; James E. O'Brien

2008-10-01

437

Heat flow in Oklahoma  

SciTech Connect

Oklahoma is one area in which terrestrial heat flow data are sparse. The thermal state of the southern mid-continent, however, is a key to understanding several important geologic problems. These include thermal anomalies associated with Paleozoic fluid migrations and the formation of Mississippi Valley-type lead-zinc deposits, the thermal evolution of the Arkoma and Anadarko sedimentary basins, and the history of hydrocarbon generation and overpressuring in the Anadarko Basin. In the late 1920s, the American Petroleum Institute made a set of equilibrium temperature logs in idle oil wells. These temperature data are generally regarded as being high quality, accurate estimates of rock temperature and they cover the entire central part of Oklahoma. Average thermal gradients in the API survey range from 14 to 43 [sup 0]C/km (average 31.2 [sup 0]C/km) over depth intervals that extend from the surface to a an average depth of 961 m. Geothermal gradients decrease from NNE to SSW. The observed change in thermal gradients could be due to a number of factors. The change in thermal gradients could simply reflect changes in lithology and thermal conductivity. Alternatively, the variation in thermal gradients could be indicative of a change in heat flow related perhaps to variations in the concentration of radioactive heat-producing elements in the crust or heat transport by one or more regional groundwater flow systems. We are proceeding to reduce ambiguity in interpretation by estimating heat flow from thermal conductivity measurements on drill cuttings and heat production from available gamma-ray logs which penetrate basement rocks.

Cranganu, C.; Deming, D. (Univ. of Oklahoma, Norman, OK (United States))

1996-01-01

438

Precision Heating Process  

NASA Technical Reports Server (NTRS)

A heat sealing process was developed by SEBRA based on technology that originated in work with NASA's Jet Propulsion Laboratory. The project involved connecting and transferring blood and fluids between sterile plastic containers while maintaining a closed system. SEBRA markets the PIRF Process to manufacturers of medical catheters. It is a precisely controlled method of heating thermoplastic materials in a mold to form or weld catheters and other products. The process offers advantages in fast, precise welding or shape forming of catheters as well as applications in a variety of other industries.

1992-01-01

439

Solar heat collector assembly  

SciTech Connect

A solar heat collector assembly includes a cylindrical transparent tube having an open end portion hermetically sealed by the use of a sealant and being held in vacuum state and a heat-collecting pipe secured in the transparent tube with its end portion extending outside the transparent tube through the sealant. The sealant is made of a thermally-nonconducting and anti-corrosion material with a softening point higher than that of the transparent tube. Especially, the sealant is made of ceramics or crystallized glass.

Shimada, M.; Katto, A.

1983-10-18

440

Heat exchanger panel  

NASA Technical Reports Server (NTRS)

The present invention relates to a heat exchanger panel which has broad utility in high temperature environments. The heat exchanger panel has a first panel, a second panel, and at least one fluid containment device positioned intermediate the first and second panels. At least one of the first panel and the second panel have at least one feature on an interior surface to accommodate the at least one fluid containment device. In a preferred embodiment, each of the first and second panels is formed from a high conductivity, high temperature composite material. Also, in a preferred embodiment, the first and second panels are joined together by one or more composite fasteners.

Warburton, Robert E. (Inventor); Cuva, William J. (Inventor)

2005-01-01

441

Heat Shields for Aerobrakes  

NASA Technical Reports Server (NTRS)

Performances of three types of heat protectors predicted. Estimates of expected performances of heat shields for conical drag brake presented in paper. Drag brakes, or aerobrakes, being considered as devices for slowing space vehicles when they return to Space Shuttle altitudes from higher satellite altitudes after supply missions. Aerobrakes add less weight than do retro-rockets for same purpose and consume no fuel. Paper provides general information on sensitivity of performance to thermal and physical properties of materials used in aerobrakes. Information useful to both designers of brakes and developers of materials for brake fabrication on aerospace structures.

Pitts, W. C.; Murbach, M. S.

1987-01-01

442

Acoustical heat pumping engine  

DOEpatents

The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium. 2 figs.

Wheatley, J.C.; Swift, G.W.; Migliori, A.

1983-08-16

443

Fully balanced heat interferometer  

NASA Astrophysics Data System (ADS)

A tunable and balanced heat interferometer is proposed and analyzed. The device consists of two superconductors linked together to form a double-loop interrupted by three parallel-coupled Josephson junctions. Both superconductors are held at different temperatures, allowing the heat currents flowing through the structure to interfere. We demonstrate that thermal transport is coherently modulated through the application of a magnetic flux. Furthermore, such modulation can be tailored at will or even suppressed through the application of an extra control flux. Such a device allows for a versatile operation appearing as an attractive key to the onset of low-temperature coherent caloritronic circuits.

Martínez-Pérez, M. J.; Giazotto, F.

2013-03-01

444

Optical heat flux gauge  

DOEpatents

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MacArthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

445

Optical heat flux gauge  

DOEpatents

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MaCarthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

446

Optical heat flux gauge  

DOEpatents

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator wherein each thermographic layer comprises a plurality of respective thermographic phosphors. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MacArthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

447

Heat distribution ceramic processing method  

DOEpatents

A multi-layered heat distributor system is provided for use in a microwave process. The multi-layered heat distributors includes a first inner layer of a high thermal conductivity heat distributor material, a middle insulating layer and an optional third insulating outer layer. The multi-layered heat distributor system is placed around the ceramic composition or article to be processed and located in a microwave heating system. Sufficient microwave energy is applied to provide a high density, unflawed ceramic product.

Tiegs, Terry N. (Lenoir City, TN); Kiggans, Jr., James O. (Oak Ridge, TN)

2001-01-01

448

Shedding More Light and Less Heat on the Results of School Integration. The Georgia Experience.  

ERIC Educational Resources Information Center

One hundred and eighty-eight Georgia school system superintendents were polled in the Spring of 1976 as to their perceptions and experiences concerning the effects of school integration. This paper presents the results of this investigation. Three broad areas were selected for analysis: (1) integration outcomes affecting the public schools, (2)…

Christison, Milton; Sida, Donald

449

On-Line Monitoring and Diagnostics of the Integrity of Nuclear Plant Steam Generators and Heat Exchangers.  

SciTech Connect

The overall purpose of this Nuclear Engineering Education Research (NEER) project was to integrate new, innovative, and existing technologies to develop a fault diagnostics and characterization system for nuclear plant steam generators (SG) and heat exchangers (HX). Issues related to system level degradation of SG and HX tubing, including tube fouling, performance under reduced heat transfer area, and the damage caused by stress corrosion cracking, are the important factors that influence overall plant operation, maintenance, and economic viability of nuclear power systems. The research at The University of Tennessee focused on the development of techniques for monitoring process and structural integrity of steam generators and heat exchangers. The objectives of the project were accomplished by the completion of the following tasks. All the objectives were accomplished during the project period. This report summarizes the research and development activities, results, and accomplishments during June 2001-September 2004. (1) Development and testing of a high-fidelity nodal model of a U-tube steam generator (UTSG) to simulate the effects of fouling and to generate a database representing normal and degraded process conditions. Application of the group method of data handling (GMDH) method for process variable prediction. (2) Development of a laboratory test module to simulate particulate fouling of HX tubes and its effect on overall thermal resistance. Application of the GMDH technique to predict HX fluid temperatures, and to compare with the calculated thermal resistance. (3) Development of a hybrid modeling technique for process diagnosis and its evaluation using laboratory heat exchanger test data. (4) Development and testing of a sensor suite using piezo-electric devices for monitoring structural integrity of both flat plates (beams) and tubing. Experiments were performed in air, and in water with and without bubbly flow. (5) Development of advanced signal processing methods using wavelet transforms and image processing techniques for isolating flaw types. (6) Development and implementation of a new nonlinear and non-stationary signal processing method, called the Hilbert-Huang transform (HHT), for flaw detection and location. This is a more robust and adaptive approach compared to the wavelet transform. (7) Implementation of a moving-window technique in the time domain for detecting and quantifying flaw types in tubular structures. A window zooming technique was also developed for flaw location in tubes. (8) Theoretical study of elastic wave propagation (longitudinal and shear waves) in metallic flat plates and tubing with and without flaws. (9) Simulation of the Lamb wave propagation using the finite-element code ABAQUS. This enabled the verification of the experimental results. The research tasks included both analytical research and experimental studies. The experimental results helped to enhance the robustness of fault monitoring methods and to provide a systematic verification of the analytical results. The results of this research were disseminated in scientific meetings. A journal manuscript was submitted for publication. The new findings of this research have potential applications in aerospace and civil structures. The report contains a complete bibliography that was developed during the course of the project.

Belle R. Upadhyaya; J. Wesley Hines

2004-09-27

450

Silicon heat pipes for cooling electronics  

SciTech Connect

The increasing power density of integrated circuits (ICs) is creating the need for improvements in systems for transferring heat away from the chip. In earlier investigations, diamond films were used to conduct heat from ICs and spread the energy across a heat sink. The authors` investigation has indicated that a 635 {mu}m (25 mil) thick silicon substrate with embedded heat pipes could perform this task better than a diamond film. From their study, it appears that the development of a heat-pipe heat-spreading system is both technically and commercially feasible. The major challenge for this heat-spreading system is to develop an effective wick structure to transport liquid to the heated area beneath the chip. This paper discusses the crucial design parameters for this heat-pipe system, such as the required wick properties, the material compatibility issues, and the thermal characteristics of the system. The paper also provides results from some recent experimental activities at Sandia to develop these heat-pipe heat spreader systems.

Adkins, D.R.; Shen, D.S.; Palmer, D.W.; Tuck, M.R.

1994-12-31

451

Radiative heat transfer in porous uranium dioxide  

SciTech Connect

Due to low thermal conductivity and high emissivity of UO{sub 2}, it has been suggested that radiative heat transfer may play a significant role in heat transfer through pores of UO{sub 2} fuel. This possibility was computationally investigated and contribution of radiative heat transfer within pores to overall heat transport in porous UO{sub 2} quantified. A repeating unit cell was developed to model approximately a porous UO{sub 2} fuel system, and the heat transfer through unit cells representing a wide variety of fuel conditions was calculated using a finite element computer program. Conduction through solid fuel matrix as wekk as pore gas, and radiative exchange at pore surface was incorporated. A variety of pore compositions were investigated: porosity, pore size, shape and orientation, temperature, and temperature gradient. Calculations were made in which pore surface radiation was both modeled and neglected. The difference between yielding the integral contribution of radiative heat transfer mechanism to overall heat transport. Results indicate that radiative component of heat transfer within pores is small for conditions representative of light water reactor fuel, typically less than 1% of total heat transport. It is much larger, however, for conditions present in liquid metal fast breeder reactor fuel; during restructuring of this fuel type early in life, the radiative heat transfer mode was shown to contribute as much as 10-20% of total heat transport in hottest regions of fuel.

Hayes, S.L. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States)

1992-12-01

452

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

NASA Technical Reports Server (NTRS)

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.

1979-01-01

453

Evaluation of the Vuilleumier heat pump for heating applications  

NASA Astrophysics Data System (ADS)

The feasibility and limitations of a Vuilleumier heat pump used for heating houses are discussed. Mathematical models of an idealized pump are used to analyze heat transfer problems at hot, intermediate, and cold operating temperatures. Solid gas heat transfer at low and intermediate temperatures poses most problems. The performance coefficient is limited (the ratio of the heat rejected at the intermediate temperature to the heat supplied at the high temperature) to 1.9. The pressure level must be dropped to comply with safety regulations.

Nykyri, M.; Hiismaeki, P.

1981-08-01

454

Heat Flux Sensor Testing  

Microsoft Academic Search

This viewgraph presentation provides information on the following objectives: Developing secondary calibration capabilities for MSFC's (Marshall Space Flight Center) Hot Gas Facility (HGF), a Mach 4 Aerothermal Wind Tunnel; Evaluating ASTM (American Society for Testing and Materials) slug\\/ thinskin calorimeters against current HGF heat flux sensors; Providing verification of baselined AEDC (Arnold Engineering Development Center) \\/ Medtherm gage calibrations; Addressing

D. W. Clark

2002-01-01

455

Solid state heat engine  

Microsoft Academic Search

A compact solid state turbine heat engine can be devised by pairing the nitinol elements. Each element is characterized by being in thermal contact with at least one hot water and one cold water bath and mechanically coupled to at least one driven pulley and driver pulley. A second nitinol element is similarly configured with a driver pulley, driven pulley,

Cory

1981-01-01

456

Solar heating and you  

SciTech Connect

This fact sheet for use with primary school classes describes what solar collectors are and how they work, passive solar rooms, flat-plate collectors, and why one should use solar heating systems. Making a solar air heater is described step-by-step with illustrations. A resource list for both students and teachers is provided for further information.

NONE

1994-08-01

457

Ceramic Heat Pipe Wick.  

National Technical Information Service (NTIS)

A wick for use in a capillary loop pump heat pipe is disclosed. The wick material is an essentially uniformly porous, permeable, open-cell, silicon dioxide/aluminum oxide inorganic ceramic foam having a silica fiber ratio, by weight, of about 78 to 22, re...

B. Seidenberg T. Swanson

1989-01-01

458

Electricity from waste heat  

NASA Astrophysics Data System (ADS)

In industry and in ships, large amounts of waste heat with quite a high release temperature are produced: examples are combustion gases and the exhaust gases of ceramic kilns. Very often they cannot be used for heating purposes because of long transport distances or because there is no local district heating network. Thus, a practical solution would be to convert this waste heat into electric power. This conversion may be carried out using an ORC-plant (Organic Rankine Cycle). There are probably some twenty ORC-plants in commercial use in the world. They are, however, usually based on conventional power plant technology, and are rather expensive, complicated and may have significant maintenance expenses. In order to obviate these problems, a project was started at Lappeenranta University of Technology at the beginning of 1981 to develop a high-speed, hermetic turbogenerator as the prime mover of the ORC. With this new technology the whole ORC-plant is quite simple, with only one moving part in the power system. It is expected to require very little maintenance, and the calculations made give for it significantly lower specific price than for the conventional technology ORC-plant. Two complete prototypes of the new technology ORC-plant have been built, one to the laboratory, other to industrial use. The nominal output of both is 100 kW electricity. Calculated amortization times for the new ORC-plant range from 2.1 to 6.

Larjola, Jaakko; Lindgren, Olli; Vakkilainen, Esa

459

Fuel injection heating system  

Microsoft Academic Search

This patent describes heating system and apparatus for a fuel injector of an internal combustion engine of a vehicle. It comprises a fuel injector including a hollow housing with a fuel inlet and a fuel outlet; an electric fuel pump for delivering fuel to the inlet of the injector; the fuel injector having a valve member therein cooperative with the

Asmus

1989-01-01

460

Flexible Heat Pipe  

NASA Technical Reports Server (NTRS)

Narrow Tube carries 10 watts or more to moving parts. Heat pipe 12 inches long and diameter of 0.312 inch (7.92mm). Bent to minimum radius of 2.5 blocks. Flexible section made of 321 stainless steel tubing (Cajon Flexible Tubing or equivalent). Evaporator and condenser made of oxygen free copper. Working fluid methanol.

Bienert, W. B.; Wolf, D. A.

1985-01-01

461

Szilard's heat engine  

NASA Astrophysics Data System (ADS)

Szilard presented the first concrete embodyment of a Maxwell demon. We present a detailed kinematic analysis of his