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1

Modular Heat Exchanger With Integral Heat Pipe  

NASA Technical Reports Server (NTRS)

Modular heat exchanger with integral heat pipe transports heat from source to Stirling engine. Alternative to heat exchangers depending on integrities of thousands of brazed joints, contains only 40 brazed tubes.

Schreiber, Jeffrey G.

1992-01-01

2

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

3

Heat Integrate Heat Engines in Process Plants  

E-print Network

Technology Conference, Houston, TX, June 17-19, 1986 CONSTANT TEMPERATLRE HEAT SINK TMI I a. IDEAL HEAT PUMP ac I CONSTANT TEMPERATURE HEAT SOURCE Tc I Figure 3. A Reversed Heat Engine THE PINCH In this section we analyze the problem of heat... integration of ideal engines with a process. The fundamental concepts so developed apply equally to real machines which are discussed in subsequent sec tions. In [1] we saw how fundamentally important the pinch concept is in the design of Heat Exchanger...

Hindmarsh, E.; Boland, D.; Townsend, D. W.

4

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

5

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

6

Integration of heat pumps into industrial processes  

SciTech Connect

The Department of Energy and others have funded studies to assess the potential for energy savings using industrial heat pumps. The studies included classifications of heat pumps, economic evaluations, and placement of heat pumps in industrial processes. Pinch technology was used in the placement studies to determine the placement, size, and type of heat pumps for a given applications. There appears to be considerable scope for heat pumping in several industries, but, where maximum process energy savings are desired, it is important to consider heat pumping in the context of overall process integration. 19 refs., 15 figs.

Chappell, R.N. (USDOE, Washington, DC (USA)); Priebe, S.J. (EG and G Idaho, Inc., Idaho Falls, ID (USA))

1989-01-01

7

Thermoelectricity from wasted heat of integrated circuits  

NASA Astrophysics Data System (ADS)

We demonstrate that waste heat from integrated circuits especially computer microprocessors can be recycled as valuable electricity to power up a portion of the circuitry or other important accessories such as on-chip cooling modules, etc. This gives a positive spin to a negative effect of ever increasing heat dissipation associated with increased power consumption aligned with shrinking down trend of transistor dimension. This concept can also be used as an important vehicle for self-powered systems-on-chip. We provide theoretical analysis supported by simulation data followed by experimental verification of on-chip thermoelectricity generation from dissipated (otherwise wasted) heat of a microprocessor.

Fahad, Hossain; Hasan, Md.; Li, Guodong; Hussain, Muhammad

2013-06-01

8

Heat Integration and Heat Recovery at a Large Chemical Manufacturing Plant  

E-print Network

opportunities for heat recovery and heat integration were identified. A feasibility study and economic analysis were performed on the two opportunities, and both projects were implemented. The first project utilized the heat contained in a distillation process...

Togna, K .A.

2012-01-01

9

Value of electrical heat boilers and heat pumps for wind power integration  

E-print Network

that the CHP plants deliver heat to. In situations combining a large heat demand, low electricity demand will be covered by electricity production coming from heat demand driven electricity production from CHP plantsValue of electrical heat boilers and heat pumps for wind power integration Peter Meibom Juha

10

An Integrated Low Level Heat Recovery System  

E-print Network

A large amount of low level thermal energy is lost to air or water in a typical petroleum refinery. This paper discusses a complex integrated low level heat recovery system that is being engineered for installation in a large petroleum refinery...

Sierra, A. V., Jr.

1981-01-01

11

Characterization of an integrated micro heat pipe  

Microsoft Academic Search

The characterization of a micro heat pipe system, integrated with a local heater, temperature and capacitive microsensors is presented. Two liquid charging schemes based on a single hole, requiring vacuum environment, and a pair of holes, utilizing capillary forces are compared. Taking advantage of the great disparity between the dielectric constants of liquids and gases, capacitance sensors are used for

Man Lee; Man Wong; Yitshak Zohar

2003-01-01

12

Path-integral formulation of ion heating  

SciTech Connect

A description of the generation and evolution of ionospheric oxygen-ion conic distributions by electromagnetic ion-cyclotron-resonance heating is formulated in terms of a path integral. All of the relevant physics is contained in this path integral, which may be used to calculate measurable properties of the conic distribution. Although the presentation is applied to this specific ionospheric context, the treatment may be generalized to treat other diffusion problems of interest.

Crew, G.B.; Chang, T.

1986-11-01

13

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

14

Active heat transfer enhancement in integrated fan heat sinks  

E-print Network

Modern computer processors require significant cooling to achieve their full performance. The "efficiency" of heat sinks is also becoming more important: cooling of electronics consumes 1% of worldwide electricity use by ...

Staats, Wayne Lawrence

2012-01-01

15

Finite-time Thermodynamic Analysis of Controlled Heat Integration  

E-print Network

a heat pump to the system, such heat pumps operate between two temperatures and result in a modified HEN among many systems. Thus we treat an ideal version of the heat integration problem engineers faceFinite-time Thermodynamic Analysis of Controlled Heat Integration James D. Nulton1 and Peter

Salamon, Peter

16

Integrated heat exchange and heat storage system using low-temperature reactions  

Microsoft Academic Search

An integrated heat exchange and heat storage system using thermochemical reactions which comprises a first plurality of parallel adjacent tubes containing an element for storing and yielding heat; and a second plurality of tubes parallel to said first plurality of tubes and interposed therebetween and containing a fluid heat vehicle, the first and second plurality of tubes being disposed in

U. Buzzi; F. Farfaletti-casali; L. Nobel; F. Reiter

1982-01-01

17

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

18

Process Integration of Industrial Heat Pumps  

E-print Network

properly relative to the process pinch and the unit operations in the process. The shape of the grand composite curve, the type of heat ?pump drive, and the kind of heat pump cycle were examined to determine their effects on the placement of industrial... processes, 2) the "multiple pinch'" prob lem, and 3) a comparison of heat pump types and cycles. PINCH TECHNOLOGY i Although pinch technology is not a new cpn cept (2,3,4), it is just beginning to be wide1y understood and appreciated. Since the prope...

Priebe, S. J.; Chappell, R. N.

19

Targeting procedures for energy savings by heat integration across plants  

Microsoft Academic Search

Heat integration across plants can be accomplished either directly using process streams or indirectly using intermediate fluids. By applying pinch analysis to a system of two plants, it is first shown that the heat transfer leading effectively to energy savings occurs at temperature levels between the pinch points of both plants. In some cases, however, heat transfer in other regions

Hernán Rodera; Miguel J. Bagajewicz

1999-01-01

20

Energy savings in heat-integrated distillation columns  

Microsoft Academic Search

The heat-integrated distillation column (HIDiC) provides one of the most effective applications of heat-pump technologies to industrial processes. It reinforces a separation process and yields larger energy savings than other methods such as overhead-to-reboiler heat pumps, which involve moving heat between the hottest and coldest points in the distillation column. A simulation study of this column has been applied to

M. Nakaiwa; K. Huang; M. Owa; T. Akiya; T. Nakane; M. Sato; T. Takamatsu

1997-01-01

21

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

22

Initial characterization of a modular heat exchanger with an integral heat pipe  

NASA Technical Reports Server (NTRS)

As part of the Civil Space Technology Initiative (CSTI) Advanced Technology program, a conceptual design of the Stirling space engine (SSE) was generated. The overall goal of the CSTI high capacity power element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space missions. The free-piston Stirling engine (FPSE) was chosen as the growth option in the CSTI program. A major goal during the conceptual design of the SSE was to reduce the number of critical joints. One area of concern was the heat exchanger assemblies that typically have the majority of critical joints. The solution proposed in the SSE conceptual design used 40 modular heat exchangers. Each module has its own integral heat pipe to transport heat from the heat source to the engine. A demonstration of the modular concept was undertaken before committing to the detailed design of the SSE heat exchangers. An existing FPSE was modified as a test bed for modular heat exchanger evaluation. The engine incorporated three heat exchanger modules, each having a sodium filled heat pipe. The thermal loading of these modules was intended to be similar to the conditions projected for the SSE modules. The engine was assembled and tests are underway. The design and fabrication of the heat exchanger modules and the engine used for these tests were described. Evaluation of the individual heat pipes before installation in the engine is described. The initial test results with the modules in operation on the engine were presented. Future tests involving the engine were outlined.

Schreiber, Jeffrey G.

1989-01-01

23

Efficiency improvements by geothermal heat integration in a lignocellulosic biorefinery.  

PubMed

In an integrated geothermal biorefinery, low-grade geothermal heat is used as process heat to allow the co-products of biofuel production to become available for higher-value uses. In this paper we consider integrating geothermal heat into a biochemical lignocellulosic biorefinery so that the lignin-enriched residue can be used either as a feedstock for chemicals and materials or for on-site electricity generation. Depending on the relative economic value of these two uses, we can maximize revenue of a biorefinery by judicious distribution of the lignin-enriched residue between these two options. We quantify the performance improvement from integrating geothermal energy for an optimized system. We then use a thermodynamic argument to show that integrating geothermal heat into a biorefinery represents an improvement in overall resource utilization efficiency in all cases considered. Finally, possible future technologies for electricity generation are considered which could improve this efficiency further. PMID:20659793

Sohel, M Imroz; Jack, Michael

2010-12-01

24

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

25

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

26

Model of a thermal energy storage device integrated into a solar assisted heat pump system for space heating  

Microsoft Academic Search

Details about modelling a sensible heat thermal energy storage (TES) device integrated into a space heating system are given. The two main operating modes are described. Solar air heaters provide thermal energy for driving a vapor compression heat pump. The TES unit ensures a more efficient usage of the collected solar energy. The TES operation is modeled by using two

Viorel Badescu

2003-01-01

27

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

28

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

29

A closer look at integrally finned-tube heat exchangers  

SciTech Connect

Extensive research has been done on the mechanisms of heat transfer, yet much of the technology that has evolved from these endeavors is underutilized. For example, the integrally finned-tube heat exchanger has been used in refrigeration for evaporators, recuperators and condensers, as well as in refinery reboilers. However, the exchanger`s use in other applications, such as reboilers, gas coolers and condensers, has been relatively slow to catch on. Perhaps this is because of a lack of knowledge and appreciation of this type of shell-and-tube exchanger. Although many papers have been written about the successful use of integral fin tubes, no volume on them, along with a readable guide to the practical application and utilization of finned-tube exchangers, is in existence. This paper attempts to remedy this lack by summarizing the advantages and applications of this type of heat exchanger.

Pase, G.K. Sr. [Joseph Oat Corp., Camden, NJ (United States)

1996-02-01

30

THE DYNAMICS OF CHEMICAL REACTORS WITH HEAT INTEGRATION  

E-print Network

) and independently Schuman (1929) as the first to present a thermal analysis of packed beds. Van Heerden (1953,1967) and Pareja and Reilly (1969). The fixed bed reactor is discussed exten­ sively in the survey of Schmitz (1975 the stability of the heat integrated fixed bed reactor. Vakil et al. (1973), Wall­ mann et al. (1979), Foss et

Skogestad, Sigurd

31

Development of a Residential Ground-Source Integrated Heat Pump  

SciTech Connect

A residential-size ground-source integrated heat pump (GSIHP) system has been developed and is currently being field tested. The system is a nominal 2-ton (7 kW) cooling capacity, variable-speed unit, which is multi-functional, e.g. space cooling, space heating, dedicated water heating, and simultaneous space cooling and water heating. High-efficiency brushless permanent-magnet (BPM) motors are used for the compressor, indoor blower, and pumps to obtain the highest component performance and system control flexibility. Laboratory test data were used to calibrate a vapor-compression simulation model (HPDM) for each of the four primary modes of operation. The model was used to optimize the internal control options and to simulate the selected internal control strategies, such as controlling to a constant air supply temperature in the space heating mode and a fixed water temperature rise in water heating modes. Equipment performance maps were generated for each operation mode as functions of all independent variables for use in TRNSYS annual energy simulations. These were performed for the GSIHP installed in a well-insulated 2600 ft2(242 m2) house and connected to a vertical ground loop heat exchanger(GLHE). We selected a 13 SEER (3.8 CSPF )/7.7 HSPF (2.3 HSPF, W/W) ASHP unit with 0.90 Energy Factor (EF) resistance water heater as the baseline for energy savings comparisons. The annual energy simulations were conducted over five US climate zones. In addition, appropriate ground loop sizes were determined for each location to meet 10-year minimum and maximum design entering water temperatures (EWTs) to the equipment. The prototype GSIHP system was predicted to use 52 to 59% less energy than the baseline system while meeting total annual space conditioning and water heating loads.

Rice, C Keith [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Hern, Shawn [ClimateMaster, Inc.] [ClimateMaster, Inc.; McDowell, Tim [Thermal Energy System Specialists, LLC] [Thermal Energy System Specialists, LLC; Munk, Jeffrey D [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL

2013-01-01

32

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

33

Heat pipe array heat exchanger  

DOEpatents

A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

Reimann, Robert C. (Lafayette, NY)

1987-08-25

34

Heat assisted magnetic recording performance and integration challenges  

NASA Astrophysics Data System (ADS)

Recent recording areal density and integrated drive performance demonstrations using Heat Assisted Magnetic Recording (HAMR) suggest that it is a viable technology to succeed conventional magnetic recording. However challenges still remain for the near field transducer, in particular reliability and sufficient thermal confinement. We explore a new NFT design, Near field Transducer Gap (NTG), which offers the potential to mitigate some of the issues in track confinement and thermal profile compared to earlier published studies [4]. The design offers efficiency improvements, and the potential to reduce unwanted background light and heating that can lead to erasure in the writing track, and neighbors.

Rea, Chris; Scholz, Werner; Cao, Lina; Peng, Chubing; Blaber, Martin; Hohfeld, Julius; Chen, Weibin; Olson, Heidi; Benakli, Mourad; Zhou, Hua; Lu, Pu-Ling; Gokemeijer, Nils; Seigler, Mike; Gao, Kaizhong; Wu, Alexander; Thiele, Jan-Ulrich; Ju, Ganping; Gage, Edward

2014-09-01

35

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

36

Site-wide process integration for low grade heat recovery  

Microsoft Academic Search

Large quantities of unrecovered low-grade heat are wasted across the process industry. Wide range of technologies and design options for recovering low grade heat are available, including heat pumps, organic Rankine cycle (ORC), energy recovery from gas turbine exhaust, absorption refrigeration, and boiler feed water heating. However, it is not straightforward to identify the most appropriate technology to be implemented,

Ankur Kapil; Igor Bulatov; Robin Smith; Jin-Kuk Kim

2011-01-01

37

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.

38

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

39

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

40

Final design and testing of a low-pressure drop heat exchanger with integral heat pipe  

NASA Astrophysics Data System (ADS)

The paper describes the design of a heat pipe heat exchanger (HPHX) compatible with capillary pumped loop (CPL) thermal control systems and the results of performance tests conducted at a CPL test facility. Steady-state tests evaluated HPHX performance parametrically as a function of condenser saturation temperature, heat exchanger temperature difference, and heat exchanger heat load. Transient tests evaluated HPHX performance as a function of normally occurring thermal control system transient events, such as heat load changes, heat sink temperature changes, and thermal control system setpoint change. An HPHX compatible with a CPL thermal control system was successfully tested. The selected condenser flow passage geometry with helix angle was proven to be a very effective condenser design. The observed condensation performance was much better than predicted due to the dramatic effect of flow turbulence on condensation effectiveness.

Fredley, J. E.; Warren, P. H.

1990-01-01

41

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

42

Water and Space Heating Heat Pumps  

E-print Network

system is an integrated air conditioning, heating and domestic hot water heating system. This system provides demand hot water heating. It has the best savings and good payback with high recovery capacity. Also, the free cooling provided during water...

Kessler, A. F.

1985-01-01

43

Air-side thermal hydraulic performance of an integrated fin and micro-channel heat exchanger  

Microsoft Academic Search

An integrated fin and micro-channel heat exchanger has been proposed. For 11 heat exchanger samples with different flow depth, fin height, fin pitch and fin thickness, a series of tests were conducted to determine their effect on the air-side thermal hydraulic performance. The heat transfer coefficient and pressure drop for heat exchangers with different geometrical configurations were reported in terms

Jiong Li; Shuangfeng Wang; Weijun Zhang

2011-01-01

44

Use of Integrated Decay Heat Limits to Facilitate Spent Nuclear Fuel Loading to Yucca Mountain  

Microsoft Academic Search

As an alternative to the use of the linear loading or areal power density (APD) concept, using integrated decay heat limits based on the use of mountain-scale heat transfer analysis is considered to represent the thermal impact from the deposited spent nuclear fuel (SNF) to the Yucca Mountain repository. Two different integrated decay heat limits were derived to represent both

Jun Li; Man-Sung Yim; David McNelis; Steven Piet

2007-01-01

45

Heat-Exchanger/Heat-Pipe Interface  

NASA Technical Reports Server (NTRS)

Monolithic assembly reliable and light in weight. Heat exchanger and evaporator ends of heat pipes integrated in monolithic halves welded together. Interface assembly connects heat exchanger of furnace, reactor, or other power source with heat pipes carrying heat to radiator or power-consuming system. One of several concepts proposed for nuclear power supplies aboard spacecraft, interface useful on Earth in solar thermal power systems, heat engines, and lightweight cooling systems.

Snyder, H. J.; Van Hagan, T. H.

1987-01-01

46

Ground Source Integrated Heat Pump (GS-IHP) Development  

SciTech Connect

Between October 2008 and May 2013 ORNL and ClimateMaster, Inc. (CM) engaged in a Cooperative Research and Development Agreement (CRADA) to develop a groundsource integrated heat pump (GS-IHP) system for the US residential market. A initial prototype was designed and fabricated, lab-tested, and modeled in TRNSYS (SOLAR Energy Laboratory, et al, 2010) to predict annual performance relative to 1) a baseline suite of equipment meeting minimum efficiency standards in effect in 2006 (combination of air-source heat pump (ASHP) and resistance water heater) and 2) a state-of-the-art (SOA) two-capacity ground-source heat pump with desuperheater water heater (WH) option (GSHPwDS). Predicted total annual energy savings, while providing space conditioning and water heating for a 2600 ft{sup 2} (242 m{sup 2}) house at 5 U.S. locations, ranged from 52 to 59%, averaging 55%, relative to the minimum efficiency suite. Predicted energy use for water heating was reduced 68 to 78% relative to resistance WH. Predicted total annual savings for the GSHPwDS relative to the same baseline averaged 22.6% with water heating energy use reduced by 10 to 30% from desuperheater contributions. The 1st generation (or alpha) prototype design for the GS-IHP was finalized in 2010 and field test samples were fabricated for testing by CM and by ORNL. Two of the alpha units were installed in 3700 ft{sup 2} (345 m{sup 2}) houses at the ZEBRAlliance site in Oak Ridge and field tested during 2011. Based on the steady-state performance demonstrated by the GS-IHPs it was projected that it would achieve >52% energy savings relative to the minimum efficiency suite at this specific site. A number of operational issues with the alpha units were identified indicating design changes needed to the system before market introduction could be accomplished. These were communicated to CM throughout the field test period. Based on the alpha unit test results and the diagnostic information coming from the field test experience, CM developed a 2nd generation (or beta) prototype in 2012. Field test verification units were fabricated and installed at the ZEBRAlliance site in Oak Ridge in May 2012 and at several sites near CM headquarters in Oklahoma. Field testing of the units continued through February 2013. Annual performance analyses of the beta unit (prototype 2) with vertical well ground heat exchangers (GHX) in 5 U.S. locations predict annual energy savings of 57% to 61%, averaging 59% relative to the minimum efficiency suite and 38% to 56%, averaging 46% relative to the SOA GSHPwDS. Based on the steady-state performance demonstrated by the test units it was projected that the 2nd generation units would achieve ~58% energy savings relative to the minimum efficiency suite at the Zebra Alliance site with horizontal GHX. A new product based on the beta unit design was announced by CM in 2012 – the Trilogy 40® Q-mode™ (http://cmdealernet.com/trilogy_40.html). The unit was formally introduced in a March 2012 press release (see Appendix A) and was available for order beginning in December 2012.

Baxter, V. D. [ORNL; Rice, K. [ORNL; Murphy, R. [ORNL; Munk, J. [ORNL; Ally, Moonis [ORNL; Shen, Bo [ORNL; Craddick, William [ORNL; Hearn, Shawn A. [ClimateMaster, Inc.

2013-05-24

47

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

48

Novel integral method for the convection-diffusion heat equation  

SciTech Connect

Motivated by the desire to implement accurate and efficient nodal methods into thermal-hydraulics production codes, a nodal integral method (NIM) has been developed for the linear steady-state convection-diffusion heat equation and solved iteratively. Current NIMs for convection-diffusion problems employ direct solvers such as Newton-Raphson, rather then iterative schemes, which make them less suitable for use in large-scale production codes that use iterations between momentum and energy modules. The NIM developed here, for a given velocity field, solves the energy equation iteratively, making it possible to implement it as a module in production codes. The simple iterative scheme for the NIM described here converges very well and the method has a 0(h[sup 2]) error.

Michael, E.P.E.; Dorning, J.J.; Rizwan-uddin (Univ. of Virginia, Charlottesville, VA (United States)); Gelbard, E.M. (Argonne National Lab., IL (United States))

1993-01-01

49

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 integrated thermal protection systems and heat resistant structures for reentry vehicles. Due to changes within NASA's Exploration Initiative, this task was cancelled early. This presentation provides an overview of the work that was accomplished prior to cancellation. The Snecma team chose an Apollo-type capsule as the reference vehicle for the work. They began with the design of a ceramic aft heatshield (CAS) utilizing C/SiC panels as the capsule heatshield, a C/SiC deployable decelerator and several ablators. They additionally developed a health monitoring system, high temperature structures testing, and the insulation characterization. Though the task was pre-maturely cancelled, a significant quantity of work was accomplished.

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

2006-01-01

50

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

51

Heat Illness  

MedlinePLUS

... dangerous levels and you can develop a heat illness. Most heat illnesses occur from staying out in ... Heat-related illnesses include Heatstroke - a life-threatening illness in which body temperature may rise above 106° ...

52

Integration of absorption heat pumps in a Kraft pulp process for enhanced energy efficiency  

Microsoft Academic Search

A preliminary feasibility study of the implementation of various absorption heat pump configurations in a Kraft pulping process has been performed. Three different cases were considered: (i) integration of a double lift heat transformer into the heat recovery circuit of the wood chips digesters to produce low pressure steam equivalent to 25% of the steam demand of the chemical pulping

Andrea Costa; Bahador Bakhtiari; Sebastian Schuster; Jean Paris

2009-01-01

53

System design optimization for large building integrated solar heating systems for domestic hot water  

Microsoft Academic Search

Performance and economy for building integrated solar domestic hot water (DHW) heating systems have been calculated as a function of installed solar collector area per housing unit, and benefits from having a high summer solar fraction are calculated and discussed. A presentation of new Danish solar heating DHW demonstration projects, where a high solar fraction is combined with heat loss

P PEDERSEN

1993-01-01

54

Heat integration retrofit analysis of a heat exchanger network of a fluid catalytic cracking plant  

Microsoft Academic Search

The impact of a process system on environmental pollution has both a local and global effect. The performance of the heat exchanger network (HEN) in a plant is an important aspect of energy conservation. Pinch technology and its recent extensions offer an effective and practical method for designing the HEN for new and retrofit projects.The fluid catalytic cracking (FCC) is

Badr Abdullah Al-Riyami; Jiri Klemeš; Simon Perry

2001-01-01

55

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

56

Heat shock genes - integrating cell survival and death.  

PubMed

Heat shock induced gene expression and other cellular responses help limit the damage caused by stress and thus facilitate cellular recovery. Cellular damage also triggers apoptotic cell death through several pathways. This paper briefly reviews interactions of the major heat shock proteins with components of the apoptotic pathways. Hsp90, which acts as a chaperone for unstable signal transducers to keep them poised for activation, interacts with RIP and Akt and promotes NF-kappa B mediated inhibition of apoptosis; in addition it also blocks some steps in the apoptotic pathways. Hsp70 is mostly anti-apoptotic and acts at several levels like inhibition of translocation of Bax into mitochondria, release of cytochrome c from mitochondria,formation of apoptosome and inhibition of activation of initiator caspases. Hsp70 also modulates JNK,NF-kappa B and Akt signaling pathways in the apoptotic cascade. In contrast, Hsp60 has both anti-and pro-apoptotic roles. Cytosolic Hsp60 prevents translocation of the pro-apoptotic protein Bax into mitochondria and thus promotes cell survival but it also promotes maturation of procaspase-3,essential for caspase mediated cell death. Our recent in vivo studies show that RNAi for the Hsp60D in Drosophila melanogaster prevents induced apoptosis. Hsp27 exerts its anti-apoptotic influence by inhibiting cytochrome c and TNF-mediated cell death. alpha beta crystallin suppresses caspase-8 and cytochrome c mediated activation of caspase-3. Studies in our laboratory also reveal that absence or reduced levels of the developmentally active as well as stress induced non-coding hsr omega transcripts, which are known to sequester diverse hnRNPs and related nuclear RNA-binding proteins,block induced apoptosis in Drosophila. Modulation of the apoptotic pathways by Hsps reflects their roles as "weak links" between various "hubs" in cellular networks. On the other hand, non-coding RNAs, by virtue of their potential to bind with multiple proteins,can act as "hubs" in these networks. In view of the integrative nature of living systems, it is not surprising that stress-induced genes,generally believed to primarily function in cell survival pathways, inhibit or even promote cell death pathways at multiple levels to ensure homeostasis at cell and/or organism level. The heat shock genes obviously do much more than merely help cells survive stress. PMID:17536179

Arya, Richa; Mallik, Moushami; Lakhotia, Subhash C

2007-04-01

57

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

58

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 chal- lenging: (i) The extreme anisotropy between the parallel (i.e., along the magnetic field), , and the perpendicular, , conductivities ( / may exceed 1010 in fusion plasmas); (ii) Magnetic field lines chaos which in general complicates (and may preclude) the construction of magnetic field line coordinates; and (iii) Nonlocal parallel transport in the limit of small collisionality. 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 geom- etry. 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 chain), 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 closures, is non-diffusive, thus casting doubts on the appropriateness of the applicability of quasilinear diffusion descriptions. General conditions for the existence of non-diffusive, multivalued flux-gradient relations in the temperature evolution are derived.

Del-Castillo-Negrete, Diego B [ORNL; Chacon, Luis [ORNL

2012-01-01

59

Heating Safety  

MedlinePLUS

... for heating. • Have a qualified professional install stationary space heating equipment, water heaters or central heating equipment according to the local codes and manufacturer’s instructions. • Maintain heating ... • For fuel burning space heaters, always use the proper fuel as specified ...

60

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

61

Seminario de Matemtica Aplicada "Improving the accuracy of heat balance integral methods  

E-print Network

Seminario de Matemática Aplicada "Improving the accuracy of heat balance integral methods (HBIMs and refined heat balance integral methods applied to a variety of phase change problems. These include to test the accuracy of the approximate solutions. We give an overview of the development of this method

Tradacete, Pedro

62

Integration and Optimization of Trigeneration Systems with Solar Energy, Biofuels, Process Heat and Fossil Fuels  

E-print Network

at developing a systematic approach to integrate solar energy into industrial processes to drive thermal energy transfer systems producing power, cool, and heat. Solar energy is needed to be integrated with other different energy sources (biofuels, fossil fuels...

Tora, Eman

2012-02-14

63

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

64

Design and development of integral heat pipe/thermal energy storage devices. [used with spacecraft cryocoolers  

NASA Technical Reports Server (NTRS)

The major design and performance test subtasks in the development of small (200 to 1,000 whr) integral heat pipe/thermal energy storage devices for use with thermally driven spacecraft cryo-coolers are described. The design of the integral heat pipe/thermal energy storage device was based on a quasi steady resistance heat transfer, lumped capacitance model. Design considerations for the heat pipe and thermal storage annuli are presented. The thermomechanical stress and insulation system design for the device are reviewed. Experimental correlations are described, as are the plans for the further development of the concept.

Mahefkey, E. T.; Richter, R.

1981-01-01

65

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

66

Integrated exhaust and electrically heated particulate filter regeneration systems  

DOEpatents

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

67

Designer heating  

Microsoft Academic Search

This article discusses the use of hydronic radiant heat as wall units and as systems installed in floors. Described are radiators made in Europe that are said to be superior to convective hydronic heat (the heating principal traditional baseboard units use). The new panel radiators are stocked by only a few US distributors and may cost 20 to 90 percent

1989-01-01

68

Heat hugger  

Microsoft Academic Search

A fireplace insert is disclosed which will efficiently heat the interior of a structure, enable control of fuel burn rate and temperature of heated air directed into the interior structure, and facilitate circulation of the heated air through the interior rooms of the structure via pressure differential created by the forced-air flow through the insert. The unit includes an airtight

Ruegg

1981-01-01

69

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

70

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

71

Hot-Spot Detection in Integrated Circuits by Substrate Heat-Flux Sensing  

Microsoft Academic Search

This letter presents a novel approach to detect hot spots (HSs) in active integrated circuits (ICs) and devices. It is based on sensing the HS heat flux within the chip substrate with a probe-laser beam. As the beam passes through the die, it experiences a deflection directly proportional to the heat flux found along its trajectory (internal infrared laser deflection

X. Perpina; J. Altet; X. Jorda; M. Vellvehi; J. Millan; N. Mestres

2008-01-01

72

A Novel Integrated Frozen Soil Thermal Energy Storage and Ground-Source Heat Pump System  

E-print Network

In this paper, a novel integrated frozen soil thermal energy storage and ground-source heat pump (IFSTS&GSHP) system in which the GHE can act as both cold thermal energy storage device and heat exchanger for GSHP is first presented. The IFSTS...

Jiang, Y.; Yao, Y.; Rong, L.; Ma, Z.

2006-01-01

73

Nonballistic heat conduction in an integrable random-exchange Ising chain studied with quantum master equations  

E-print Network

Nonballistic heat conduction in an integrable random-exchange Ising chain studied with quantum numerically investigate the heat conduction in a random-exchange Ising spin chain by using the quantum master equation. The chain is subject to a uniform transverse field h, while the exchange couplings Qn between

Li, Baowen

74

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

75

Preliminary analysis of heat pipe heat exchangers for heat recovery  

Microsoft Academic Search

A preliminary analysis of fin tube heat pipe heat exchangers for air-to-air heat recovery was conducted. The analysis uses conventional heat exchanger design techniques and a new heat pipe design technique which includes probabilistic design of artery wick heat pipes. The heat transfer capability of the heat pipes may be matched with that of the finned tubes in order to

J. O. Amode; K. T. Feldman

1975-01-01

76

Optimal Operation System of the Integrated District Heating System with Multiple Regional Branches  

NASA Astrophysics Data System (ADS)

This paper presents an optimal production and distribution management for structural and operational optimization of the integrated district heating system (DHS) with multiple regional branches. A DHS consists of energy suppliers and consumers, district heating pipelines network and heat storage facilities in the covered region. In the optimal management system, production of heat and electric power, regional heat demand, electric power bidding and sales, transport and storage of heat at each regional DHS are taken into account. The optimal management system is formulated as a mixed integer linear programming (MILP) where the objectives is to minimize the overall cost of the integrated DHS while satisfying the operation constraints of heat units and networks as well as fulfilling heating demands from consumers. Piecewise linear formulation of the production cost function and stairwise formulation of the start-up cost function are used to compute nonlinear cost function approximately. Evaluation of the total overall cost is based on weekly operations at each district heat branches. Numerical simulations show the increase of energy efficiency due to the introduction of the present optimal management system.

Kim, Ui Sik; Park, Tae Chang; Kim, Lae-Hyun; Yeo, Yeong Koo

77

Integrated thermal-fluidic I\\/O interconnects for an on-chip microchannel heat sink  

Microsoft Academic Search

Power dissipation in microprocessors will reach a level that necessitates chip-level liquid cooling in the near future. An on-chip microfluidic heat sink can reduce the thermal interfaces between an IC chip and the convective cooling medium. Through wafer-level processing, integrated thermal-fluidic I\\/O interconnects enable on-chip microfluidic heat sinks with ultrasmall form factor at low-cost. This letter describes wafer-level integration of

Bing Dang; Muhannad S. Bakir; James D. Meindl

2006-01-01

78

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

79

Designer heating  

SciTech Connect

This article discusses the use of hydronic radiant heat as wall units and as systems installed in floors. Described are radiators made in Europe that are said to be superior to convective hydronic heat (the heating principal traditional baseboard units use). The new panel radiators are stocked by only a few US distributors and may cost 20 to 90 percent more than for American-style units of equal heating capacity. Because of their attractiveness and custom sizes the units may be mounted on open walls. Also described are advances in radiant floor heating. New systems have improved plastic tubing, more installation options, smarter controls and better edge insulation. The disadvantage in radiant floor heating is that floors may not be covered by heavy carpets or rugs.

Flower, R.G.

1989-03-01

80

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

81

Fundamentals of solar heating  

SciTech Connect

Economic aspects of solar heating are covered, including simple payback methods and life-cycle costing. Basic thermodynamic principles are reviewed. Insolation is introduced. Kinds of heat losses and methods of calculating heating loads are discussed. Flat-plate collector design is covered, including thermal analysis, performance, and sizing. Heat storage is briefly discussed. The basic theory and design of heat distribution systems are described. Integration of the collector and storage into an active solar system is discussed, and some applications are presented. Solar swimming pool heating is covered. The SOLRAD program that is used in the study of collector orientation is listed. (LEW)

Schubert, R.C.; Ryan, L.D.

1981-01-01

82

PCB-Integrated Heat Exchanger for Cooling Electronics Using Microchannels Fabricated With the Direct-Write Method  

Microsoft Academic Search

The electronic industry has a growing need for efficient heat dissipation mechanisms such as micro heat exchanger systems. This active cooling approach requires the integration of microfluidic components near the main heat sources of the electronic devices. Despite the investigation of several micro-cooling configurations, their commercial utilization by the electronic industry is rather limited due to complex fabrication and integration

Ramzi Bey Oueslati; Daniel Therriault; Sylvain Martel

2008-01-01

83

Heat Transfer  

Microsoft Academic Search

\\u000a We are now stepping into the traditional physical chemistry area known as thermodynamics. Thermodynamics is concerned with a change of the total energy of a system. A system is a body which performs work (–w) or gives away heat (?q); the same body can also receive work (+w) or heat (+q). Notice the sign: when you carry out work or

Predrag-Peter Ilich

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

The DOE Heat-Pump-Centered Integrated Community Energy Systems Project  

NASA Astrophysics Data System (ADS)

The Heat-Pump-Centered Integrated Community Energy Systems Project seeks to conserve energy by developing heat pump systems for district heating and cooling. Seven contractor teams were involved in concept development and subsequent application feasibility studies. A technical and economic assessment of the systems developed was performed based on the results of these and two related studies. The assessment concludes that district heating and cooling with heat pumps can conserve energy resources, and particularly nonrenewable fuels, in an environmentally and economically attractive way. The application potential is believed to be broad, and the energy savings of widespread implementation would be substantial. No one system is universally applicable, but many options exists. Market forces are already promoting many of the required technologies, but further research, development, and demonstration could accelerate implementation.

Calm, J. M.

1982-03-01

86

Enhancing flow boiling heat transfer in microchannels for thermal management with monolithically-integrated silicon nanowires.  

PubMed

Thermal management has become a critical issue for high heat flux electronics and energy systems. Integrated two-phase microchannel liquid-cooling technology has been envisioned as a promising solution, but with great challenges in flow instability. In this work, silicon nanowires were synthesized in situ in parallel silicon microchannel arrays for the first time to suppress the flow instability and to augment flow boiling heat transfer. Significant enhancement in flow boiling heat transfer performance was demonstrated for the nanowire-coated microchannel heat sink, such as an early onset of nucleate boiling, a delayed onset of flow oscillation, suppressed oscillating amplitudes of temperature and pressure drop, and an increased heat transfer coefficient. PMID:22694316

Li, D; Wu, G S; Wang, W; Wang, Y D; Liu, Dong; Zhang, D C; Chen, Y F; Peterson, G P; Yang, Ronggui

2012-07-11

87

Innovative heat removal structure for power devices -the drift region integrated microchannel cooler  

E-print Network

devices and modules. This is due to the large heat exchange surface, the high heat transfer coefficient the heat transfer coefficient and the ratio surface/volume of the heat exchanger, the resulting significant

Boyer, Edmond

88

Investigation of a radiantly heated and cooled office with an integrated desiccant ventilation unit  

E-print Network

and cooling has been supplied in several forms, including floor heating, ceiling heating and cooling, radiant panels and façade heating and cooling. Among them, façade heating and cooling is the most recently developed system. This dissertation provides a...

Gong, Xiangyang

2009-05-15

89

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

90

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

91

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

92

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

93

Experiments and modelling of an integrated preferential oxidation–heat exchanger microdevice  

Microsoft Academic Search

Microreactor technology creates opportunities for the development of miniature chemical devices, in which several unit operations are integrated. We describe in this paper the design, experimental, and modelling work concerning a microdevice for the preferential oxidation of carbon monoxide in hydrogen-rich reformate gas. The microdevice consists of two heat exchangers and one reactor, all integrated in a single stack of

E. R. Delsman; G. J. Kramer; P. D. Cobden; Ch. Hofmann; V. Cominos; J. C. Schouten

2004-01-01

94

An integrated safe shutdown heat removal system for light water reactors  

Microsoft Academic Search

A design concept is introduced for an integrated safe shutdown heat removal system (ISSS) for light water reactors that is independent of all components and systems outside the primary containment, other than elements of the ISSS itself, which includes an integral stored water supply. A principle theme is to obtain simple, reliable, and highly protected means for water makeup and

J. C. Ebersole; D. Okrent

1976-01-01

95

Heat pipe array heat exchanger  

Microsoft Academic Search

A heat exchanger is described for transferring heat between a first fluid and a second fluid in an absorption refrigeration system comprising: a first shell having an inlet for receiving the first fluid at a first elevated temperature and an outlet for discharging the first fluid at a first reduced temperature with the shell defining a free flow path for

Reimann

1987-01-01

96

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

97

Heat pipe heat exchanger for heat recovery in air conditioning  

Microsoft Academic Search

The heat pipe heat exchangers are used in heat recovery applications to cool the incoming fresh air in air conditioning applications. Two streams of fresh and return air have been connected with heat pipe heat exchanger to investigate the thermal performance and effectiveness of heat recovery system. Ratios of mass flow rate between return and fresh air of 1, 1.5

Mostafa A. Abd El-Baky; Mousa M. Mohamed

2007-01-01

98

Corrosive resistant heat exchanger  

DOEpatents

A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

Richlen, Scott L. (Annandale, VA)

1989-01-01

99

Measurements of the Influence of Integral Length Scale on Stagnation Region Heat Transfer  

NASA Technical Reports Server (NTRS)

The purpose was twofold: first, to determine if a length scale existed that would cause the greatest augmentation in stagnation region heat transfer for a given turbulence intensity and second, to develop a prediction tool for stagnation heat transfer in the presence of free stream turbulence. Toward this end, a model with a circular leading edge was fabricated with heat transfer gages in the stagnation region. The model was qualified in a low turbulence wind tunnel by comparing measurements with Frossling's solution for stagnation region heat transfer in a laminar free stream. Five turbulence generating grids were fabricated; four were square mesh, biplane grids made from square bars. Each had identical mesh to bar width ratio but different bar widths. The fifth grid was an array of fine parallel wires that were perpendicular to the axis of the cylindrical leading edge. Turbulence intensity and integral length scale were measured as a function of distance from the grids. Stagnation region heat transfer was measured at various distances downstream of each grid. Data were taken at cylinder Reynolds numbers ranging from 42,000 to 193,000. Turbulence intensities were in the range 1.1 to 15.9 percent while the ratio of integral length scale to cylinder diameter ranged from 0.05 to 0.30. Stagnation region heat transfer augmentation increased with decreasing length scale. An optimum scale was not found. A correlation was developed that fit heat transfer data for the square bar grids to within +4 percent. The data from the array of wires were not predicted by the correlation; augmentation was higher for this case indicating that the degree of isotropy in the turbulent flow field has a large effect on stagnation heat transfer. The data of other researchers are also compared with the correlation.

Vanfossen, G. James; Ching, Chang Y.

1994-01-01

100

Simulation of Power Delivery Networks with Joule Heating Effects for 3D Integration Jianyong Xie and Madhavan Swaminathan  

E-print Network

Simulation of Power Delivery Networks with Joule Heating Effects for 3D Integration Jianyong Xie Joule heating and convection effects. The finite volume formulations of DC voltage drop equation temperature distribution with convection and Joule heating effects. The simulation results show that even

Swaminathan, Madhavan

101

The integration of water loop heat pump and building structural thermal storage systems  

SciTech Connect

Many commercial buildings need heat in one part and, at the same time, cooling in another part. Even more common is the need for heating during one part of the day and cooling during another in the same spaces. If that energy could be shifted or stored for later use, significant energy might be saved. If a building's heating and cooling subsystems could be integrated with the building's structural mass and used to collect, store, and deliver energy, the energy might be save cost-effectively. To explore this opportunity, researchers at the Pacific Northwest Laboratory (PNL) examined the thermal interactions between the heating, ventilating, and air-conditioning (HVAC) system and the structure of a commercial building. Computer models were developed to simulate the interactions in an existing building located in Seattle, Washington, to determine how these building subsystems could be integrated to improve energy efficiency. The HVAC subsystems in the existing building were modeled. These subsystems consist of decentralized water-source heat pumps (WSHP) in a closed water loop, connected to cooling towers for heat rejection during cooling mode and boilers to augment heating. An initial base case'' computer model of the Seattle building, as-built, was developed. Metered data available for the building were used to calibrate this model to ensure that the analysis would provide information that closely reflected the operation of a real building. The HVAC system and building structure were integrated in the model using the concrete floor slabs as thermal storage media. The slabs may be actively charged during off-peak periods with the chilled water in the loop and then either actively or passively discharged into the conditioned space during peak periods. 21 refs., 37 figs., 17 tabs.

Marseille, T.J.; Schliesing, J.S.

1991-10-01

102

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

103

Design Approach and Performance Analysis of a Small Integrated Heat Pump (IHP) for Net Zero Energy Homes (NEH)  

Microsoft Academic Search

This paper describes the design and performance analysis of a variable-capacity heat pump system developed for a small (1800ft2 (167 m2)) prototype net ZEH with an average design cooling load of 1.25 tons (4.4 kW) in five selected US climates. The heat pump integrates space heating and cooling, water heating, ventilation, and humidity control (humidification and dehumidification) functions into a

C. Keith Rice; Richard W. Murphy; Van D. Baxter

2008-01-01

104

An efficient way to use medium-or-low temperature solar heat for power generation – integration into conventional power plant  

Microsoft Academic Search

This paper demonstrates that the medium-or-low temperature solar heat can be used to generate power efficiently by integrating into conventional coal-fired power plants. In so-called solar aided power generation (SAPG) technology, medium-or-low temperature solar heat is used to replace parts of bled-off steams in regenerative Rankine cycle to pre-heat feedwater. Thermal oil can be used as solar heat carrier and

Yongping Yang; Qin Yan; Rongrong Zhai; Abbas Kouzani; Eric Hu

2011-01-01

105

THE DYNAMICS OF CHEMICAL REACTORS WITH HEAT INTEGRATION  

E-print Network

1929 as the rst to present a thermal analysis of packed beds. Van Heerden 1953 and Aris and Amundson. The xed bed reactor is discussed exten- sively in the survey of Schmitz 1975 and in the further survey integrated xed bed reactor. Vakil et al. 1973, Wall- mann et al. 1979, Foss et al. 1980 and Wallman and Foss

Skogestad, Sigurd

106

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

107

Integrated modelling of process heat transfer with combustion and fouling  

Microsoft Academic Search

This paper provides a summary of the main project topics which contribute to a major study aimed at integrating fouling and combustion activities. Brief outlines of the aims of the 14 main activities are provided along with examples of results from work on time-dependent fouling, industrial measurements, particle deposition tests, engineering combustion modelling, CFB modelling, sonic control and optimisation tests.

J. D. Isdale; P. Mercier; J. M. Grillot; A. Mulholland; J. Gomatam

1997-01-01

108

Heat generation from electronics increases with the advent of high-density integrated circuit technology. To  

E-print Network

film coating, heat exchangers, combustors, fuel processors, and biomedical and biochemical analysis of a representative microchannel heat exchanger is presented in Fig. 1. Heat flux (q) is applied from the vertical

Boyer, Edmond

109

Integrated thermal engineering analyses with heat transfer at periphery of planar solid oxide fuel cell  

NASA Astrophysics Data System (ADS)

This paper focuses on the thermal engineering design and analysis of solid oxide fuel cell (SOFC) units, with emphasis on cell performance and component design. In engineering practice, insulation materials would be deployed as the enclosure of an SOFC stack to reduce the heat loss to the environment. In this work, a computational methodology has been implemented to characterize the thermal engineering performance of a planar SOFC. The present calculation procedure integrates the steady-sate electrochemical reactions of the SOFC with finite-element models for thermo-mechanical analyses of the interconnect through iteration processes, so that a unified temperature distribution with heat loss effect can be obtained. Present results show that the convergent rate of the adopted methodology is quite efficient, and that the temperature patterns are compatible with those reported in the literature. Furthermore, this work has also developed a bulk heat-transfer model for simplified design analysis. The concept of total heat resistance is employed to facilitate the one-dimensional (1D) analyses and to determine the predominant parameters that affect heat-transfer behaviour. Moreover, some accommodation factors have been deduced to correlate the 1D results of lateral heat transfer with those of two-dimensional (2D) finite-element analyses, as this will be beneficial for rapid prototyping processes.

Chyou, Yau-Pin; Chung, Tsang-Dong; Chen, Jong-Sheng; Shie, Ri-Fong

110

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

111

Evaporative heat transfer in mesoscale heat exchangers  

Microsoft Academic Search

An application for an integrated array of small (mesoscale) cooling devices is introduced and a survey of related research is provided. A test apparatus appropriate for experiments with small-scale, low-capacity evaporators is described. Two-phase pressure drop and heat transfer data are presented for R-134a in a heat exchanger consisting of an inlet manifold, 52 parallel channels, and an exit manifold.

S. S. Mehendale; A. M. Jacobi

2000-01-01

112

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.

113

Integral transform analysis of MHD flow and heat transfer in parallel-plates channels  

Microsoft Academic Search

A hybrid solution through the so-called Generalized Integral Transform Technique (GITT) is obtained for the MHD flow and heat transfer of a Newtonian fluid in parallel-plates channels. A simple mathematical formulation for the problem is adopted, which evidences both the transient regime flow sustainable only by a constant pressure gradient; and the steady state situation that considers both a constant

João A. Lima; João N. N. Quaresma; Emanuel N. Macêdo

2007-01-01

114

Fuel-efficiency of hydrogen and heat storage technologies for integration of fluctuating renewable energy sources  

Microsoft Academic Search

This paper presents the methodology and results of analysing the use of different energy storage technologies in the task of integration of fluctuating renewable energy sources (RES) into the electricity supply. The analysis is done on the complete electricity system including renewable energy sources as well as power plants and CHP (combined heat and power production). Emphasis is put on

Brian Vad Mathiesen; Henrik Lund

2005-01-01

115

Evaluation of hybrid optimization methods for the optimal design of heat integrated distillation sequences  

Microsoft Academic Search

Optimal process design often requires the solution of mixed integer non-linear programming problems. Optimization procedures must be robust and efficient if they are to be incorporated in automated design systems. For heat integrated separation process design, a natural hybrid evolutionary\\/local search method with these properties is possible. The method is based on the use of local search methods for the

E. S. Fraga

2003-01-01

116

Process integration methodology for natural gas-fueled heat pumps and cogeneration systems  

Microsoft Academic Search

A process integration methodology was developed for analyzing industrial processes, identifying those that will benefit from natural gas fueled heat pumps and cogeneration system as well as novel, process-specific opportunities for further equipment improvements, including performance targets. The development included the writing of software to assist in implementing the methodology and application of the procedures in studies using both literature

Alan P. Rossiter

1988-01-01

117

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

118

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

119

Numerical study on air-side performance of an integrated fin and micro-channel heat exchanger  

Microsoft Academic Search

A new type of aluminum heat exchanger with integrated fin and micro-channel has been proposed. The air-side heat transfer and flow characteristics of the integrated fin and micro-channel heat exchanger are systematically analyzed by a 3D numerical simulation. The effect of flow depth, fin height, fin pitch and fin thickness at different Reynolds number is evaluated by calculating Colburn factor

Jiong Li; Shuangfeng Wang; Wang Cai; Weijun Zhang

2010-01-01

120

Evaporative heat transfer in mesoscale heat exchangers  

SciTech Connect

An application for an integrated array of small (mesoscale) cooling devices is introduced and a survey of related research is provided. A test apparatus appropriate for experiments with small-scale, low-capacity evaporators is described. Two-phase pressure drop and heat transfer data are presented for R-134a in a heat exchanger consisting of an inlet manifold, 52 parallel channels, and an exit manifold. Each individual channel has a cross-sectional flow area 800 {micro}m by 800 {micro}m and 74 {micro}m long. Experiments are conducted over a range of conditions, with flow rates up to 0.48 g/s, inlet qualities from 7% to 15%, and an evaporating temperature of approximately 10 C. The heat exchanger operated with a pressure drop of less than about 8 kPa and provided a heat transfer coefficient greater than 8,000 W/(m{sup 2}{center_dot}K). The heat transfer data suggest that nucleate boiling dominates for flow rates below an equivalent Reynolds number (Re{sub eq}) of about 40 in a channel. A comparison of the pressure drop and heat transfer results to related data from the literature shows general agreement and supports these promising results for mesoscale heat exchangers.

Mehendale, S.S.; Jacobi, A.M.

2000-07-01

121

Bayonet heat exchangers in heat-assisted Stirling heat pump  

SciTech Connect

The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

1998-07-01

122

Ceramic heat pipe heat exchangers  

Microsoft Academic Search

High-temperature strength, resistance to corrosive atmospheres, and moderate cost combine to make ceramic materials an obvious choice for construction of high-temperature thermal energy recuperator systems. Despite these advantages, ceramic recuperators are steadily being replaced by metallic units at considerable sacrifice in maximum air or fuel preheat temperatures and hence in recovery efficiency. By constructing a recuperator from ceramic heat pipes,

W. A. Ranken

1976-01-01

123

Analysis and utilization of Joule heating in an electromagnet integrated microfluidic device for biological applications  

Microsoft Academic Search

Joule heating in the electromagnetic cell sorting system is problematic. Our micro-device was fabricated for the rapid separation by high magnetic field gradients of electromagnet and dissipates the Joule heat energy that causes unnecessary heat-up in the device. By using a cooling channel embedded in microfluidic channel, Joule heat can be reduced to dissipate thermal energy to an active area

Suk-Heung Song; Bong-Seop Kwak; Hyo-Il Jung

2009-01-01

124

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

125

Heat exchange system for recycling stack heat  

Microsoft Academic Search

A heat exchange system is described for recycling waste heat leaving a building stack to supply heat to incoming fresh air or temper stored water of the building water storage system, wherein the building has a source of heat at constant temperature, such as a cooking facility, from which air conveying waste heat is drawn and impelled through a stack

Giuffre

1980-01-01

126

Waste heat recovery using heat pipe heat exchanger for heating automobile using exhaust gas  

Microsoft Academic Search

The feasibility of using heat pipe heat exchangers for heating applying automotive exhaust gas is studied and the calculation method is developed. Practical heat pipe heat exchanger is set up for heating HS663, a large bus. Simple experiments are carried out to examine the performance of the heat exchanger. It is shown that the experimental results, which indicate the benefit

Feng Yang; Xiugan Yuan; Guiping Lin

2003-01-01

127

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

128

Heat pump system  

DOEpatents

An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

1982-01-01

129

Summer HeatSummer Heat Heat stress solutions  

E-print Network

Gardening and Your Health: Gardening and Your Health: Summer HeatSummer Heat Heat stress solutions their effectiveness and possibly causing harmful reactions to the applicator. Allow yourself to acclimate to the heat, not cold. Flavored beverages, such as fruit juices, iced tea and lemonade, as long as their sugar and salt

Liskiewicz, Maciej

130

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

SciTech Connect

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 proposed control strategy. The results obtained so far continue to support the AS-IHP being a promising candidate to meet the energy service needs for DOE's development of a Zero Energy Home (ZEH) by the year 2020.

Murphy, Richard W [ORNL; Rice, C Keith [ORNL; Baxter, Van D [ORNL; Craddick, William G [ORNL

2007-07-01

131

Project title: Natural ventilation, solar heating and integrated low-energy building design  

E-print Network

emissions targets. That is why the Cambridge-MIT Institute set up a project to design buildings that consume less energy. The Challenge Their work focuses on the design of energy efficient buildings that use natural ventilation processes, solar... Awards E-stack brings a breath of fresh air to UK schools HOME ABOUT US FUNDING OPPORTUNITIES PROJECTS EDUCATION NEWS EVENTS DOWNLOADS CONTACT US PROJECTS Natural Ventilation Solar Heating and Integrated Low-Energy Building Design SEARCH: Go Page 1...

2009-07-10

132

Heat-pump-centered integrated community energy systems: System development assessment  

NASA Astrophysics Data System (ADS)

An assessment of 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. Natural sources including solar and geothermal heat, heat stored on an annual cycle from summer cooling, and otherwise-wasted heat from industrial and commercial processes may be effectively used by the systems described. Fifteen system analyses are examined. The assessment concludes that district heating with heat pumps can conserve energy resources, and particularly scarce fuels, in an environmental and economically attractive way. The application potential is believed to be broad, and the energy savings of widespread implementation would be substantial. No one system is universally applicable, but many system options exist. Market forces are already promoting many of the required technologies, but further research, development, and demonstration could accelerate implementation.

Calm, J. M.; Sapienza, G. R.; Biederman, N. P.

1981-03-01

133

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

134

Heat pipe heat exchanger design considerations  

Microsoft Academic Search

Typical heat pipe heat exchangers (HPHX) are described, along with their advantages, uses, and some problems in HPHX design, and a computer HPHX analysis program is discussed with required input data. The computer program is being developed for analysis of heat exchange performance by finned-tube HPHX and thread-puddle-artery heat pipes. Copper-water heat pipes and carbon steel-Dowtherm A heat pipes are

K. T. Feldman; D. C. Lu

1976-01-01

135

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

136

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

137

Heat pipe waste heat recovery boilers  

NASA Astrophysics Data System (ADS)

The use of heat pipes as transport devices in waste heat recovery boilers is examined. Test results show that heat pipes can efficiently extract heat from the hot gas stream and transfer it inside the pressure vessel for the steam generation process. The benefits of incorporating heat pipes into the design of waste heat recovery boilers include a highly compact package, a significant reduction in thermally induced stresses, double isolation of the steam from the heat source, an extended surface for improved efficiency in heat extraction, improved circulation and stability in the boiling regime, easy cleaning, individually replaceable tubes, and low flue gas pressure drop.

Littwin, D. A.; McCurley, J.

138

Dead heat  

SciTech Connect

This paper reports on the prospect of global warming. This paper proposes a workable solution, and a road map for getting there. The author explains how we became addicted to fossil fuels and evokes a bleak picture should this dependence continue. But the book also explores how industry can become a vehicle for solving, instead of precipitating, the global environmental crisis. The decoupling of energy from pollution can be accomplished without sacrificing prosperity by powering the economy with solar energy. Dead Heat takes us step by step to a greenhouse-friendly world fueled only by the sun.

Oppenheimer, M.; Boyle, R.H.

1990-01-01

139

Heat Pipes Cool Power Magnetics  

NASA Technical Reports Server (NTRS)

Configurations originally developed for space use are effective in any orientation. Heat pipes integrated into high-power, high-frequency, highvoltage spaceflight magnetics reduce weight and improve reliability by lowering internal tempertures. Two heat pipes integrated in design of power transformer cool unit in any orientation. Electrostatic shield conducts heat from windings to heat pipe evaporator. Technology allows dramatic reductions in size and weight, while significantly improving reliability. In addition, all attitude design of heat pipes allows operation of heat pipes independent of local gravity forces.

Hansen, I.; Chester, M.; Luedke, E.

1983-01-01

140

Exact path-integral evaluation of the heat distribution function of a trapped brownian oscillator.  

PubMed

Using path integrals, we derive an exact expression--valid at all times t--for the distribution P(Q,t) of the heat fluctuations Q of a brownian particle trapped in a stationary harmonic well. We find that P(Q,t) can be expressed in terms of a modified Bessel function of zeroth order that in the limit t?? exactly recovers the heat distribution function obtained recently by Imparato [Phys. Rev. E 76, 050101(R) (2007)] from the approximate solution to a Fokker-Planck equation. This long-time result is in very good agreement with experimental measurements carried out by the same group on the heat effects produced by single micron-sized polystyrene beads in a stationary optical trap. An earlier exact calculation of the heat distribution function of a trapped particle moving at a constant speed v was carried out by van Zon and Cohen [Phys. Rev. E 69, 056121 (2004)]; however, this calculation does not provide an expression for P(Q,t) itself, but only its Fourier transform (which cannot be analytically inverted), nor can it be used to obtain P(Q,t) for the case v=0 . PMID:21230434

Chatterjee, Debarati; Cherayil, Binny J

2010-11-01

141

Exact path-integral evaluation of the heat distribution function of a trapped Brownian oscillator  

NASA Astrophysics Data System (ADS)

Using path integrals, we derive an exact expression—valid at all times t —for the distribution P(Q,t) of the heat fluctuations Q of a Brownian particle trapped in a stationary harmonic well. We find that P(Q,t) can be expressed in terms of a modified Bessel function of zeroth order that in the limit t?? exactly recovers the heat distribution function obtained recently by Imparato [Phys. Rev. E 76, 050101(R) (2007)]10.1103/PhysRevE.76.050101 from the approximate solution to a Fokker-Planck equation. This long-time result is in very good agreement with experimental measurements carried out by the same group on the heat effects produced by single micron-sized polystyrene beads in a stationary optical trap. An earlier exact calculation of the heat distribution function of a trapped particle moving at a constant speed v was carried out by van Zon and Cohen [Phys. Rev. E 69, 056121 (2004)]10.1103/PhysRevE.69.056121; however, this calculation does not provide an expression for P(Q,t) itself, but only its Fourier transform (which cannot be analytically inverted), nor can it be used to obtain P(Q,t) for the case v=0 .

Chatterjee, Debarati; Cherayil, Binny J.

2010-11-01

142

Coupled heat conduction and thermal stress formulation using explicit integration. [LMFBR  

SciTech Connect

The formulation needed for the conductance of heat by means of explicit integration is presented. The implementation of these expressions into a transient structural code, which is also based on explicit temporal integration, is described. Comparisons of theoretical results with code predictions are given both for one-dimensional and two-dimensional problems. The coupled thermal and structural solution of a concrete crucible, when subjected to a sudden temperature increase, shows the history of cracking. The extent of cracking is compared with experimental data.

Marchertas, A.H.; Kulak, R.F.

1982-06-01

143

Characteristics of energy savings in an ideal heat-integrated distillation column (HIDiC)  

SciTech Connect

Distillation columns are major energy consumers in the chemical and petrochemical industries. In order to reduce energy consumption, considerable studies have been carried out and many distillation columns have been proposed. A Heat-Integrated Distillation Column (HIDiC) is constructed in such a manner that its rectifying and stripping sections are separated, while connected through a compressor and a throttling valve. Separation is benefited by heat integration between the two sections. To provide the driving forces for heat transfers from the rectifying to the stripping sections, the former must be operated at higher pressure than the latter. The HIDiC is expected to be more energy efficient than conventional columns, while at the expenses of some energy to raise up the pressure of the rectifying section. In this paper, it is shown by thermodynamical consideration that the HIDiC has high potential of exergy loss reduction compared with conventional columns. The effects of pressure difference on energy saving are analyzed, and possibility of energy saving is found in some case studies.

Nakaiwa, Masaru; Huang, Kejin; Owa, Masaru; Akiya, Takaji; Nakane, Takashi; Sato, Masahito [National Inst. of Materials and Chemical Research, Tsukuba (Japan). Dept. of Chemical Systems; Takamatsu, Takeichiro [Kyoto Univ. (Japan)

1997-12-31

144

Microchannel heat sink assembly  

DOEpatents

The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watertight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures. 13 figs.

Bonde, W.L.; Contolini, R.J.

1992-03-24

145

Microchannel heat sink assembly  

DOEpatents

The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watetight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures.

Bonde, Wayne L. (Livermore, CA); Contolini, Robert J. (Pleasanton, CA)

1992-01-01

146

Liquid over-feeding refrigeration system and method with integrated accumulator-expander-heat exchanger  

DOEpatents

A refrigeration system having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle.

Mei, Viung C. (Oak Ridge, TN); Chen, Fang C. (Knoxville, TN)

1997-01-01

147

Liquid over-feeding refrigeration system and method with integrated accumulator-expander-heat exchanger  

DOEpatents

A refrigeration system is described having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle. 4 figs.

Mei, V.C.; Chen, F.C.

1997-04-22

148

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

149

Study of heat sources interacting in integrated circuits by laser mirage effect  

NASA Astrophysics Data System (ADS)

This work exploits the mirage effect to analyze multiple heat sources thermally interacting in an integrated circuit (IC) by means of a probe IR laser beam, which strikes on the die lateral walls and passes through the die substrate. Under such conditions, the criteria for locating such hot spots, as well as their relative power dissipation, are discussed on the basis of a theoretical model inferred in this work. Finally, the technique feasibility is shown in a real application scenario, obtaining 5-?m spatial lateral resolution and an error in power dissipation measurements below 5%. This method may become a practical alternative to usual off-chip techniques for inspecting hot spots in ICs and to experimentally characterize heat flow in the semiconductor substrate.

Perpiñà, X.; Jordà, X.; Vellvehi, M.; Altet, J.

2014-08-01

150

Heat exchange system for recycling waste heat  

Microsoft Academic Search

Design of heat exchange system for recycling waste heat, such as that leaving a building stack or flue, to supply heat where needed, such as to incoming fresh air or to tempered stored water of the building water storage system, wherein the building has a source of heat at a constant temperature (such as a furnace, a cooking facility, or

A. A. Giuffre; A. F. Giuffre

1982-01-01

151

Heat transfer enhancement in heat exchangers  

Microsoft Academic Search

In the power generation industry, high performance heat exchangers are needed to promote substantial improvements in effective utilization of waste heat in low temperature heat recovery applications. High performance heat exchangers are also seriously needed in low temperature power and refrigeration cycles that operate on renewable base energy sources such as ocean thermal energy conversion, geothermal and solar energy systems.

Ohadi

1991-01-01

152

ABSORPTION HEAT PUMP IN THE DISTRICT HEATING  

E-print Network

.6 % by natural gas European Heat Pump Summit 2013, Nuremberg, 15-16.10.2013 #12;Heat production sources · DHP;Advantages: · recovering of low-grade heat · savings of natural gas annual consumption - 842,000 m3 Boiler, 116 MWth Boiler, 116 MWth Gas Turbine 31.52 MWel Heat Recovery Steam Generator, 63 t/h, 67 bar

Oak Ridge National Laboratory

153

Integrated bioenergy complex for the production of power, heat and bio-ethanol  

SciTech Connect

In this paper an integrated bioenergy complex for the production of power, heat and bio-ethanol is presented. Ethanol, in fact, has been recognized as a high-quality transportation fuel. The reduction of petroleum consumption, especially for transport, is a strategic goal especially for those countries that already have or will experience an intensive industrial development in the next future. For these motivations, the production of bio-ethanol from Sweet Sorghum (which is now one of the most promising crop for this application in term of productivity, inputs demand, and flexibility) is of great interest in most of countries. The proposed integrated complex produces power, heat and bio-ethanol: the produced power and heat are partly used for bio-ethanol processing and biomass pre-treatment, partly to be sold to the market. This system has important innovations allowing a decentralized energy and ethanol production and creating new local jobs. The small power plant is based upon a steam cycle with an advanced low emission combustor, capable of burning different biomass resources with a modest decrease in the efficiency value. The Bioenergy Complex, suitable to satisfy the needs of a 3,000 inhabitants village, is composed by the following sub-systems: (1) Sweet Sorghum plantation (250 ha); the main products are: dry bagasse (approximately 3,900 Ton/year), grains (1,300 Ton/y) and sugar (1,850 Ton/y); (2) Cane crushing--sugar juice extraction system; (3) Sugar juice fermentation and distillation ethanol production (approx. 835 Ton/y); (4) Biomass pre-treatment components (grinding, drying, briquetting, storage, etc.); and (5) Cogeneration unit--the expansion unit is constituted by a last generation reciprocating steam engine, coupled with a 500 kWe alternator; the heat of the expanded flow is removed in the condenser, with an available thermal power of approximately 2,000 kWt.

Taviani, M.; Chiaramonti, D.; Tondi, G.; Grassi, G.

1998-07-01

154

Short-term exposure to heat stress attenuates appetite and intestinal integrity in growing pigs.  

PubMed

Acute heat stress (HS) and heat stroke can be detrimental to the health, well-being, and performance of mammals such as swine. Therefore, our objective was to chronologically characterize how a growing pig perceives and initially copes with a severe heat load. Crossbred gilts (n = 32; 63.8 ± 2.9 kg) were subjected to HS conditions (37°C and 40% humidity) with ad libitum intake for 0, 2, 4, or 6 h (n = 8/time point). Rectal temperature (Tr), respiration rates (RR), and feed intake were determined every 2 h. Pigs were euthanized at each time point and fresh ileum and colon samples were mounted into modified Ussing chambers to assess ex vivo intestinal integrity and function. Transepithelial electrical resistance (TER) and fluorescein isothiocyanate-labeled dextran (FD4) permeability were assessed. As expected, Tr increased linearly over time (P < 0.001) with the highest temperature observed at 6 h of HS. Compared to the 0-h thermal-neutral (TN) pigs, RR increased (230%; P < 0.001) in the first 2 h and remained elevated over the 6 h of HS (P < 0.05). Feed intake was dramatically reduced due to HS and this corresponded with significant changes in plasma glucose, ghrelin, and glucose-dependent insulinotropic peptide (P < 0.050). At as early as 2 h of HS, ileum TER linearly decreased (P < 0.01), while FD4 linearly increased with time (P < 0.05). Colon TER and FD4 changed due to HS in quadratic responses over time (P = 0.050) similar to the ileum but were less pronounced. In response to HS, ileum and colon heat shock protein (HSP) 70 mRNA and protein abundance increased linearly over time (P < 0.050). Altogether, these data indicated that a short duration of HS (2-6 h) compromised feed intake and intestinal integrity in growing pigs. PMID:25367514

Pearce, S C; Sanz-Fernandez, M V; Hollis, J H; Baumgard, L H; Gabler, N K

2014-12-01

155

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

156

Segmented heat exchanger  

SciTech Connect

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

157

Heat recovery method  

SciTech Connect

Heat is recovered by combining a heat transfer system including heat exchangers interconnected in a circulatory system, with a heat pump system. The heat pump system is preferably operated in accordance with the Lorenz-Principle. It is not necessary to divide the heat carrier circuit of the heat pump into two or three separate circulatory circuits. The heat carrier circuit of the heat pump can thus continue to operate unchanged even if the heat pump is switched off. For this purpose the warm heat carrier coming from a discharge fluid cooler, is heated further in a condenser of the heat pump and the cold heat carrier coming from a preheater or cooler group, is cooled further in an evaporator of the heat pump.

Richarts, F.

1985-04-16

158

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. 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

159

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

160

Vertically integrated sensible-heat budgets for stable nocturnal boundary layers  

NASA Astrophysics Data System (ADS)

The stable nocturnal boundary layer is commonly viewed or modelled as a balance between the temperature tendency (cooling) and vertical heat-flux divergence. Sometimes the radiative-flux divergence is also included. This perspective has dictated the design of field experiments for investigating stable nocturnal boundary layers.Tower-based micrometeorological data from three field campaigns are analysed to evaluate the vertically integrated sensible-heat budget for nocturnal stable conditions. Our analysis indicates frequent occurrence of large imbalance between the temperature tendency and vertical heat-flux divergence terms. The values of the radiative-flux divergence are generally too small and sometimes of the wrong sign to explain the residual. An analysis of random flux errors and uncertainties in the tendency term indicate that such errors cannot explain large imbalances, suggesting the importance of advection of temperature or possibly the divergence of mesoscale fluxes. The implied role of advection is consistent with circumstantial evidence. Even weak surface heterogeneity can create significant horizontal gradients in stable boundary layers. However, it is shown that existing field data and observational strategy do not allow adequate evaluation of advection and mesoscale flux divergence terms.

Nakamura, Reina; Mahrt, L.

2006-01-01

161

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

SciTech Connect

The energy service needs of a net-zero-energy house (ZEH) include space heating and cooling, water heating, ventilation, dehumidification, and humidification, depending on the requirements of the specific location. These requirements differ in significant ways from those of current housing. For instance, the most recent DOE buildings energy data (DOE/BED 2007) indicate that on average {approx}43% of residential buildings primary energy use is for space heating and cooling, vs. {approx}12% for water heating (about a 3.6:1 ratio). In contrast, for the particular prototype ZEH structures used in the analyses in this report, that ratio ranges from about 0.3:1 to 1.6:1 depending on location. The high-performance envelope of a ZEH results in much lower space heating and cooling loads relative to current housing and also makes the house sufficiently air-tight to require mechanical ventilation for indoor air quality. These envelope characteristics mean that the space conditioning load will be closer in size to the water heating load, which depends on occupant behavior and thus is not expected to drop by any significant amount because of an improved envelope. In some locations such as the Gulf Coast area, additional dehumidification will almost certainly be required during the shoulder and cooling seasons. In locales with heavy space heating needs, supplemental humidification may be needed because of health concerns or may be desired for improved occupant comfort. The U.S. Department of Energy (DOE) has determined that achieving their ZEH goal will require energy service equipment that can meet these needs while using 50% less energy than current equipment. One promising approach to meeting this requirement is through an integrated heat pump (IHP) - a single system based on heat pumping technology. The energy benefits of an IHP stem from the ability to utilize otherwise wasted energy; for example, heat rejected by the space cooling operation can be used for water heating. With the greater energy savings the cost of the more energy efficient components required for the IHP can be recovered more quickly than if they were applied to individual pieces of equipment to meet each individual energy service need. An IHP can be designed to use either outdoor air or geothermal resources (e.g., ground, ground water, surface water) as the environmental energy source/sink. Based on a scoping study of a wide variety of possible approaches to meeting the energy service needs for a ZEH, DOE selected the IHP concept as the most promising and has supported research directed toward the development of both air- and ground-source versions. This report describes the ground-source IHP (GS-IHP) design and includes the lessons learned and best practices revealed by the research and development (R&D) effort throughout. Salient features of the GS-IHP include a variable-speed rotary compressor incorporating a brushless direct current permanent magnet motor which provides all refrigerant compression, a variable-speed fan for the indoor section, a multiple-speed ground coil circuit pump, and a single-speed pump for water heating operation. Laboratory IHP testing has thus far used R-22 because of the availability of the needed components that use this refrigerant. It is expected that HFC R-410A will be used for any products arising from the IHP concept. Data for a variable-speed compressor that uses R-410A has been incorporated into the DOE/ORNL Mark VI Heat Pump Design Model (HPDM). HPDM was then linked to TRNSYS, a time-series-dependent simulation model capable of determining the energy use of building cooling and heating equipment as applied to a defined house on a sub-hourly basis. This provided a highly flexible design analysis capability for advanced heat pump equipment; however, the program also took a relatively long time to run. This approach was used with the initial prototype design reported in Murphy et al. (2007a) and in the business case analysis of Baxter (2007).

Murphy, Richard W [ORNL; Rice, C Keith [ORNL; Baxter, Van D [ORNL; Craddick, William G [ORNL

2007-09-01

162

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

163

Design Approach and Performance Analysis of a Small Integrated Heat Pump (IHP) for Net Zero Energy Homes (ZEH)  

SciTech Connect

This paper describes the design and performance analysis of a variable-capacity heat pump system developed for a small [1800ft2 (167 m2)] prototype net ZEH with an average design cooling load of 1.25 tons (4.4 kW) in five selected US climates. The heat pump integrates space heating and cooling, water heating, ventilation, and humidity control (humidification and dehumidification) functions into a single integrated heat pump (IHP) unit. The design approach uses one small variable-capacity compressor to meet all the above functions in an energy efficient manner. Modal performance comparisons to an earlier IHP product are shown relative to the proposed new design for net ZEH application. The annual performance analysis approach using TRNSYS in conjunction with the ORNL Heat Pump Design Model is discussed. Annual performance projections for a range of locations are compared to those of a base system consisting of separate pieces of equipment to perform the same functions. The ZEH IHP is projected to reduce energy use for space heating & cooling, water heating, dehumidification, and ventilation for a net ZEH by about 50% compared to that of the base system.

Rice, C Keith [ORNL; Murphy, Richard W [ORNL; Baxter, Van D [ORNL

2008-01-01

164

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

165

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.

166

Active microchannel heat exchanger  

Microsoft Academic Search

The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The active 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

Anna Lee Y. Tonkovich; Gary L. Roberts; Charles J. Call; Robert S. Wegeng; Yong Wang

2001-01-01

167

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

168

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

169

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

170

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

171

Heat recovery unit  

Microsoft Academic Search

A device is disclosed for recovery of heat from hot shell devices, particularly from motor-compressor units such as used in air conditioners, refrigeration systems and the like and which comprises a heat exchange coil in encircling, contacting heat exchange relationship to the hot shell device with circulation of a fluid through the heat exchange coil to recover normally wasted heat.

Beckett

1980-01-01

172

Heat storage units  

Microsoft Academic Search

A heat storage unit of the kind comprising a housing in which heat storage elements are contained, with a common passage extending through the heat storage elements, and through which air is fed by a fan to remove heat from the storage elements to apply the heat to the room being served by the unit is described. To permit the

1982-01-01

173

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

174

Ceramic Heat Recuperators for Industrial Heat Recovery.  

National Technical Information Service (NTIS)

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 evalu...

1980-01-01

175

Heat Pump for High School Heat Recovery  

E-print Network

The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system...

Huang, K.; Wang, H.; Zhou, X.

2006-01-01

176

Alternative heat sources for heat pumps  

NASA Astrophysics Data System (ADS)

Solar assisted, water source, and ground source heat pumps are described as alternatives to air to air heat pumps for use in a broader range of climates. Publications for further information on these systems are listed.

1984-09-01

177

Energy Corner: Heat Reclamation Rescues Wasted Heat.  

ERIC Educational Resources Information Center

Heat reclamation systems added to pre-existing central heating systems provide maximum savings at minimum cost. The benefits of a particular appliance marketed under the brand name "Energizer" are discussed. (Author/MLF)

Daugherty, Thomas

1982-01-01

178

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

179

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

180

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

181

High heat flux single phase heat exchanger  

Microsoft Academic Search

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

Javier A. Valenzuela; Michael G. Izenson

1990-01-01

182

Unsteady heat transfer in heat pipes  

Microsoft Academic Search

The purpose was to investigate the unsteady heat transfer associated with a heat pipe during start up operation. Initial studies were conducted with a variety of heat pipe screen wick configurations in order to develop a mathematical expression for the flow velocity of a fluid inducted by the capillary structure of the wick. This mathematical model was solved first numerically

J. E. Beam

1985-01-01

183

Absorption heat pump system  

DOEpatents

The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

Grossman, G.

1982-06-16

184

Absorption heat pump system  

DOEpatents

The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

Grossman, Gershon (Oak Ridge, TN)

1984-01-01

185

Locating Heat Recovery Opportunities  

E-print Network

Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

Waterland, A. F.

1981-01-01

186

Liquid Phase Heating Systems  

E-print Network

Liquid phase heating systems involve sensible heat transfer in a closed loop wherein a pumped fluid's temperature is raised in a heater, then lowered in a heat user and returned for reheating. No formation and condensation of vapor occurs. High...

Mordt, E. H.

1979-01-01

187

Woven heat exchanger  

DOEpatents

This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

Piscitella, R.R.

1984-07-16

188

Contact Heat Exchanger  

NASA Technical Reports Server (NTRS)

Fluid pressure controls contact between heat pipe and heat exchanger. Heat exchanger system in cross section provides contact interface between fluid system and heat pipe with easy assembly/disassembly of heat-pipe/ pumped-liquid system. Originally developed for use in space, new device applicable on Earth where fluid system is linked with heat pipe, where rapid assembly/disassembly required, or where high pressures or corrosive fluids used.

Fleming, M. L.; Stalmach, D. D.; Cox, R. L.

1985-01-01

189

Interface Film Resistivities for Heat and Mass TransferssIntegral Relations Verified by Non-equilibrium Molecular Dynamics  

E-print Network

Interface Film Resistivities for Heat and Mass TransferssIntegral Relations Verified by Non; In Final Form: July 6, 2006 Integral relations that predict interface film transfer coefficients) the interface film, where transport processes are driven by jumps in temperature and chemical potential; and (3

Kjelstrup, Signe

190

Performance assessment with Pinch technology and integrated heat pumps for vaporized concentration processing  

Microsoft Academic Search

The enhancement of energy use efficiency is an urgent issue. In this study, Pinch Technology (PT) was used to assess the optimum energy use in a process. A heat pump (HP) was combined with a three-effect vacuum evaporator (TEVE) in an old and traditional food factory to recover and reuse waste heat. The Base case evaluated just the TEVE system.

Chi-I Tuan; Yi-Lung Yeh; Chi-Jen Chen; Ting-Chien Chen

191

New industrial heat pump applications to an integrated thermomechanical pulp and paper mill  

SciTech Connect

Application of pinch technology US industries in an early screening study done by TENSA Services (DOE/ID/12583-1) identified potential for heat pumps in several industrial sectors. Among these, processes with large evaporation units were found to be some of the most promising sectors for advanced heat pump placement. This report summarizes the results of a study for Bowater Incorporated, Carolina Division. The units selected for this study are the thermo-mechanical pulper (TMP), kraft digester, evaporators, boiler feed water (BFW) train and pulp dryer. Based on the present level of operation, the following recommendations are made: 1. Install a mechanical vapor compression (MVR) heat pump between the TMP mill and {number sign}3 evaporator. This heat pump will compress the 22 psig steam from the TMP heat recovery system and use it to replace about 70% of the 60 psig steam required in {number sign} evaporator. The boiler feed water heat losses (in the low pressure deaerator) will be supplied by heat available in the TMR's zero psig vent steam. 2. Study the digester to verify the practicality of installing an MVR heat pump which will compress the dirty weapons from the cyclone separator. The compressed vapors can be directly injected into the digester and thus reduce the 135 psig steam consumption. 31 figs., 9 tabs.

none,

1991-01-01

192

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

193

Methodology of optimization for microchannel heat exchanger  

Microsoft Academic Search

Heat generation from very large-scale integrated (VLSI) circuits increases with the advent of high-density integrated circuit technology. One of the promising techniques is liquid cooling by using microchannel heat exchanger. This work proposes a scheme for microchannel heat exchanger optimization with the constraint of pump. The cooling performance of microchannel heat exchanger was analyzed by constraining the flow rate and

HeeSung Park; Jongln Jo; JaeYoung Chang; SunSoo Kim

2006-01-01

194

Initial findings: The integration of water loop heat pump and building structural thermal storage systems  

SciTech Connect

This report is one in a series of reports describing research activities in support of the US Department of Energy (DOE) Commercial Building System Integration Research Program. The goal of the program is to develop the scientific and technical basis for improving integrated decision-making during design and construction. Improved decision-making could significantly reduce buildings' energy use by the year 2010. The objectives of the Commercial Building System Integration Research Program are: to identify and quantify the most significant energy-related interactions among building subsystems; to develop the scientific and technical basis for improving energy related interactions in building subsystems; and to provide guidance to designers, owners, and builders for improving the integration of building subsystems for energy efficiency. The lead laboratory for this program is the Pacific Northwest Laboratory. A wide variety of expertise and resources from industry, academia, other government entities, and other DOE laboratories are used in planning, reviewing and conducting research activities. Cooperative and complementary research, development, and technology transfer activities with other interested organizations are actively pursued. In this report, the interactions of a water loop heat pump system and building structural mass and their effect on whole-building energy performance is analyzed. 10 refs., 54 figs., 1 tab.

Marseille, T.J.; Johnson, B.K.; Wallin, R.P.; Chiu, S.A.; Crawley, D.B.

1989-01-01

195

Development of an Integrated Residential Heating, Ventilation, Cooling, and Dehumidification System for Residences  

SciTech Connect

The Need and the Opportunity Codes such as ASHRAE 90.2 and IECC, and programs such as Energy Star and Builders Challenge, are causing new homes to be built to higher performance standards. As a result sensible cooling loads in new homes are going down, but indoor air quality prerogatives are causing ventilation rates and moisture loads to increase in humid climates. Conventional air conditioners are unable to provide the low sensible heat ratios that are needed to efficiently cool and dehumidify homes since dehumidification potential is strongly correlated with cooling system operating hours. The project team saw an opportunity to develop a system that is at least as effective as a conventional air conditioner plus dehumidifier, removes moisture without increasing the sensible load, reduces equipment cost by integrating components, and simplifies installation. Project Overview Prime contractor Davis Energy Group led a team in developing an Integrated Heating, Ventilation, Cooling, and Dehumidification (I-HVCD) system under the DOE SBIR program. Phase I and II SBIR project activities ran from July 2003 through December 2007. Tasks included: (1) Mechanical Design and Prototyping; (2) Controls Development; (3) Laboratory and Field Testing; and (4) Commercialization Activities Technology Description. Key components of the prototype I-HVCD system include an evaporator coil assembly, return and outdoor air damper, and controls. These are used in conjunction with conventional components that include a variable speed air handler or furnace, and a two-stage condensing unit. I-HVCD controls enable the system to operate in three distinct cooling modes to respond to indoor temperature and relative humidity (RH) levels. When sensible cooling loads are high, the system operates similar to a conventional system but varies supply airflow in response to indoor RH. In the second mode airflow is further reduced, and the reheat coil adds heat to the supply air. In the third mode, the reheat coil adds additional heat to maintain the supply air temperature close to the return air temperature (100% latent cooling). Project Outcomes Key Phase II objectives were to develop a pre-production version of the system and to demonstrate its performance in an actual house. The system was first tested in the laboratory and subsequently underwent field-testing at a new house in Gainesville, Florida. Field testing began in 2006 with monitoring of a 'conventional best practices' system that included a two stage air conditioner and Energy Star dehumidifier. In September 2007, the I-HVCD components were installed for testing. Both systems maintained uniform indoor temperatures, but indoor RH control was considerably better with the I-HVCD system. The daily variation from average indoor humidity conditions was less than 2% for the I-HVCD vs. 5-7% for the base case system. Data showed that the energy use of the two systems was comparable. Preliminary installed cost estimates suggest that production costs for the current I-HVCD integrated design would likely be lower than for competing systems that include a high efficiency air conditioner, dehumidifier, and fresh air ventilation system. Project Benefits This project verified that the I-HVCD refrigeration compacts are compact (for easy installation and retrofit) and can be installed with air conditioning equipment from a variety of manufacturers. Project results confirmed that the system can provide precise indoor temperature and RH control under a variety of climate conditions. The I-HVCD integrated approach offers numerous benefits including integrated control, easier installation, and reduced equipment maintenance needs. Work completed under this project represents a significant step towards product commercialization. Improved indoor RH control and fresh air ventilation are system attributes that will become increasingly important in the years ahead as building envelopes improve and sensible cooling loads continue to fall. Technologies like I-HVCD will be instrumental in meeting goals set by Building America

Hoeschele, M.A.; D.A. Springer

2008-06-18

196

Innovative Miniaturized Heat Pumps for Buildings: Modular Thermal Hub for Building Heating, Cooling and Water Heating  

SciTech Connect

BEETIT Project: Georgia Tech is using innovative components and system design to develop a new type of absorption heat pump. Georgia Tech’s new heat pumps are energy efficient, use refrigerants that do not emit greenhouse gases, and can run on energy from combustion, waste heat, or solar energy. Georgia Tech is leveraging enhancements to heat and mass transfer technology possible in microscale passages and removing hurdles to the use of heat-activated heat pumps that have existed for more than a century. Use of microscale passages allows for miniaturization of systems that can be packed as monolithic full-system packages or discrete, distributed components enabling integration into a variety of residential and commercial buildings. Compared to conventional heat pumps, Georgia Tech’s design innovations will create an absorption heat pump that is much smaller, has higher energy efficiency, and can also be mass produced at a lower cost and assembly time.

None

2010-09-01

197

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

198

Urban heat island  

Microsoft Academic Search

The phenomenon of an urban heat island was investigated by the use of Landsat\\/Thematic Mapper data sets collected over the metropolitan area of Washington, DC. By combining the derived spectral albedos and temperatures, surface energy composites of five surface categories were analysed. The results indicate that urban heating is attributable to a large excess in heat from the rapidly heating

H. H. Kim

1992-01-01

199

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

200

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

201

Heat transfer dynamics  

Microsoft Academic Search

As heat transfer technology increases in complexity, it becomes more difficult for those without thermal dynamics engineering training to choose between competitive heat transfer systems offered to meet their drying requirements. A step back to the basics of heat transfer can help professional managers and papermakers make informed decisions on alternative equipment and methods. The primary forms of heat and

1994-01-01

202

Antigravity heat pipe  

Microsoft Academic Search

The general design and principle of operation of an antigravity heat pipe, in which the heat transfer agent is supplied to the evaporator against the force of gravity, are descussed. Analytical expressions describing the operation of the heat pipe are presented, as are experimental results obtained for an acetone-charged antigravity heat pipe.

N. I. Kliuev

1989-01-01

203

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

204

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

205

Solar heat pump  

NASA Astrophysics Data System (ADS)

Brief discussions of the major components of a solar powered, chemical ground source heat pump are presented. The components discussed are the solar collectors and the chemical heat storage battery. Sodium sulfide is the medium used for heat storage. Catalog information which provides a description of all of the heat pump systems is included.

Hermanson, R.

206

Mass and Heat Recovery  

E-print Network

In the last few years heat recovery was under spot and in air conditioning fields usually we use heat recovery by different types of heat exchangers. The heat exchanging between the exhaust air from the building with the fresh air to the building...

Hindawai, S. M.

2010-01-01

207

Direct fired heat exchanger  

DOEpatents

A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

1986-01-01

208

Performance of a variable conductance heat pipe heat exchanger  

Microsoft Academic Search

The performance of an air to air heat exchanger in which heat is transferred to a finned evaporator and from a finned condenser via a heat pipe was evaluated. The variable conductance heat pipe is to the condenser fins a heat source and to the evaporator fins a heat sink. The principal advantage of the variable conductance heat pipe heat

P. D. Chancelor

1983-01-01

209

Heat loss of district heating distribution networks  

SciTech Connect

The energy losses are often grouped into direct and indirect losses. Direct losses occur in the heat source, distribution network, valves etc., when heat escapes to the environment. The surplus electrical energy used for pumping is also a direct loss. Indirect losses are due to oversized, improperly selected system components, subsystem or improper mode of connection. An unnecessary or inappropriate investment may generate arises energy losses. Losses of both types are at present in Hungarian district heating systems, therefore in the course of modernization attempts on reducing those losses shall be made. Analysis and minimizing of the network losses are the subjects of our report. Computerized analysis has been made. We put in the computer data on simulation of distribution network of the district heating/thermal simulation = heat loss calculation. The network has been identified by comparing the measured figures with the data derived from computerized simulation. The paper shows some examples of calculated network heat losses under different operation conditions.

Zsebik, A.; Sztrancsik, Z.S. [Technical Univ. of Budapest (Hungary)

1996-11-01

210

Fundamentals of heat measurement. [heat flux transducers  

NASA Technical Reports Server (NTRS)

Various methods and devices for obtaining experimental data on heat flux density over wide ranges of temperature and pressure are examined. Laboratory tests and device fabrication details are supplemented by theoretical analyses of heat-conduction and thermoelectric effects, providing design guidelines and information relevant to further research and development. A theory defining the measure of correspondence between transducer signal and the measured heat flux is established for individual (isolated) heat flux transducers subject to space and time-dependent loading. An analysis of the properties of stacked (series-connected) transducers of various types (sandwich-type, plane, and spiral) is used to derive a similarity theory providing general governing relationships. The transducers examined are used in 36 types of derivative devices involving direct heat loss measurements, heat conduction studies, radiation pyrometry, calorimetry in medicine and industry and nuclear reactor dosimetry.

Gerashchenko, O. A.

1979-01-01

211

Heat pumps in district heating and district cooling systems.  

National Technical Information Service (NTIS)

This thesis presents an analysis of heat pump operation in a District Heating and District Cooling system. Two heat pumps with supersonic centrifugal compressors use untreated sewage as their heat source/sink for the simultaneous production of heating and...

M. Havskjold

1993-01-01

212

Multiple heat pipe heat exchanger and method for making  

Microsoft Academic Search

A heat pipe heat exchanger has a plurality of heat pipes which are interconnected so as to permit fluid communication between the pipes at least during charging so that the heat pipes may be simultaneously filled with heat transfer fluid.

Maxson

1979-01-01

213

Refractory heat dry considerations  

SciTech Connect

The demands of the hydrocarbon processing industry are for higher quality monolithic refractory linings. To ensure a good lining, an adequate heat dry must be performed. Unfortunately, the heat dry is often the overlooked or afterthought portion of the installation and performed in a rather haphazard manner. This article explores an actual heat dry of FCCU riser pipes lined with a heavyweight refractory. Methods of heat measurement and heat variations within the pipes during dry out are discussed.

Smith, K. (Cooperheat, Somerset, NJ (US))

1990-01-01

214

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

215

A review for the applications and integrated approaches of ground-coupled heat pump systems  

Microsoft Academic Search

During the past few decades, a large number of ground-coupled heat pump (GCHP) systems have been widely applied in various buildings around the world due to the attractive advantages of high efficiency and environmental friendliness. However, most buildings in warm-climate or cold-climate areas have unbalanced loads, dominated by either cooling loads or heating loads. Therefore, it is necessary to employ

X. Q. Zhai; M. Qu; X. Yu; Y. Yang; R. Z. Wang

2011-01-01

216

Performance evaluation of an integrated automotive air conditioning and heat pump system  

Microsoft Academic Search

This study deals with the performance characteristics of an R134a automotive air conditioning system capable of operating as an air-to-air heat pump using ambient air as a heat source. For this aim, an experimental analysis has been performed on a plant made up of original components from an automobile air conditioning system and some extra equipment employed to operate the

M. Hosoz; M. Direk

2006-01-01

217

Waste Heat Recovery with Heat Pipe Technology  

NASA Astrophysics Data System (ADS)

High grade energy, which is primarily derived from hydrocarbon fuels, is in short supply; therefore alternative energy sources such as renewable and recycled energy sources are gaining significant attention. Pyro-metallurgical processes are large consumers of energy. They in return generate large quantities of waste heat which goes un-recovered. The overall theme of this research is to capture, concentrate and convert some of this waste heat to a valuable form. The main objective is to characterize and develop heat pipe technology (some of which originated at McGill) to capture and concentrate low grade heat. Heat pipe employs boiling as the means to concentrate the energy contained in the waste heat and transfers it as higher quality energy. The distinct design features of this device (separate return line and flow modifiers in the evaporator) maximize its heat extraction capacity. During the testing the main limitations within the heat pipe were identified. Different test phases were designed throughout which the configuration of the system was modified to overcome these limitations and to increase the amount of extracted heat.

Razavinia, Nasim

218

Heat transfer by a corona wind heat exchanger  

Microsoft Academic Search

A cold plate heat exchanger fitted with pin fins and having integral corona wind blowers was constructed and tested for thermal performance. The heat exchanger was operated in air at sea level pressure and at reduced pressures with Reynold's numbers up to 300. Test in sulphur hexafluoride gas at sea level pressures demonstrated that the thermal performance was considerably better

A. S. Mitchell

1978-01-01

219

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

220

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

221

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

222

HEAT TRANSFER CHARACTERISTICS OF AN INTEGRATED COOLING CONFIGURATION FOR ULTRAHIGH TEMPERATURE TURBINE BLADES : EXPERIMENTAL AND NUMERICAL INVESTIGATIONS  

Microsoft Academic Search

This paper deals with fundamental research on heat transfer char- acteristics inside a cooling configuration designed for an ultra-high temperature turbine nozzle. The cooling configuration adopted in this study integrates impingement cooling and pin cooling devices into one body, aiming at the enhancement of the effective area for the im- pingement cooling. A large-scaled test model of this cooling system

K. Funazaki; Y. Tarukawa; T. Kudo; S. Matsuno; R. Imai; S. Yamawaki

223

Generalized boundary integral equation for heat conduction in non-homogeneous media: recent developments on the sifting property  

Microsoft Academic Search

In this paper, we address concerns which were raised with respect to the sifting property of the forcing function D which is crucial in deriving an integral equation for heat conduction in non-homogeneous media. The error in the sifting property (which we neglected in our previous papers) is expanded in a series which leads to evaluation of the error in

Eduardo Divo; Alain J. Kassab

1998-01-01

224

Building having solar heating system  

Microsoft Academic Search

A building is disclosed with an integrated solar heating system forming a part of the design of the building by a portion of the heating system being the structural support walls in the form of vertically disposed hollow vessels preferably made of metal. Insulation is applied to opposite sides of the vessels. A fluid is circulated from an upper manifold

McHugh

1981-01-01

225

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

226

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

227

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

228

Flexible Heating Head  

NASA Technical Reports Server (NTRS)

United States Air Force is investigating method of repairing aircraft by use of adhesive bonding with induction heating to cure adhesive. Fast-acting and reliable induction heating device that is lightweight, portable, and easy to use needed for such applications. Newly developed flexible heating head lightweight and conforms to complex, curved surfaces. Incorporates principles and circuitry of toroid joining gun described in "Toroid Joining Gun for Fittings and Couplings" (LAR-14278). Concentrates heat in local area through induction heating. Flexible heating head contains tank circuit, connected via cable to source of power.

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

1994-01-01

229

Save by absorption heat pumping  

SciTech Connect

The author compares absorption heat pumping (AHP) to mechanical vapor compressor (MVC) heat pumping. The moving part of the AHP is a pump easy to maintain and inexpensive to spare. The mechanical component of the MVC is a vapor compressor which requires more maintenance and is cost-prohibitive to spare. Also, in the MVC system, a purified product stream is heat pumped in an open compressor, thus risking product contamination. In the AHP system, the cold and hot utilities are heat pumped. Therefore, product integrity with an AHP system is well protected as in a conventional fractionation column.

Davidson, W.F.; Campagne, W.V.L.

1987-12-01

230

Integral Kinetic Model for Studying Quercetin Degradation and Oxidation as Affected by Cholesterol During Heating  

PubMed Central

The degradation and oxidation of quercetin, as affected by cholesterol during heating at 150 °C, was kinetically studied using non-linear regression models. Both TLC and HPLC were used to monitor the changes of quercetin, cholesterol and cholesterol oxidation products (COPs) during heating. The formation of COPs, including triol, 7-keto, 7?-OH and 7?-OH, was completely inhibited during the initial 30 minute heating period in the presence of 0.02% quercetin, accompanied by reduction in cholesterol peroxidation and degradation. However, the quercetin degradation or oxidation proceeded fast, with the rate constants (h?1) in the presence of nitrogen, oxygen and the combination of oxygen and cholesterol being 0.253, 0.868 and 7.17, respectively. When cholesterol and quercetin were heated together, the rate constants (h?1) of cholesterol peroxidation, epoxidation and degradation were 1.8 × 10?4, 0.016 and 0.19, respectively. The correlation coefficients (r2) for all the oxidative and degradation reactions ranged from 0.82–0.99. The kinetic models developed in this study may be used to predict the degradation and oxidation of quercetin as affected by cholesterol during heating. PMID:21152275

Chien, John-Tung; Hsu, Da-Jung; Inbaraj, Baskaran Stephen; Chen, Bing-Huei

2010-01-01

231

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

232

THE INTEGRATION OF PROCESS HEAT APPLICATIONS TO HIGH TEMPERATURE GAS REACTORS  

SciTech Connect

A high temperature gas reactor, HTGR, can produce industrial process steam, high-temperature heat-transfer gases, and/or electricity. In conventional industrial processes, these products are generated by the combustion of fossil fuels such as coal and natural gas, resulting in significant emissions of greenhouse gases such as carbon dioxide. Heat or electricity produced in an HTGR could be used to supply process heat or electricity to conventional processes without generating any greenhouse gases. Process heat from a reactor needs to be transported by a gas to the industrial process. Two such gases were considered in this study: helium and steam. For this analysis, it was assumed that steam was delivered at 17 MPa and 540 C and helium was delivered at 7 MPa and at a variety of temperatures. The temperature of the gas returning from the industrial process and going to the HTGR must be within certain temperature ranges to maintain the correct reactor inlet temperature for a particular reactor outlet temperature. The returning gas may be below the reactor inlet temperature, ROT, but not above. The optimal return temperature produces the maximum process heat gas flow rate. For steam, the delivered pressure sets an optimal reactor outlet temperature based on the condensation temperature of the steam. ROTs greater than 769.7 C produce no additional advantage for the production of steam.

Michael G. McKellar

2011-11-01

233

The heat pipe heat exchangers: Design, technology and applications  

Microsoft Academic Search

The Heat Pipe Heat Exchanger (HPHE) is a relatively new and very attractice heat exchanger type. For a good understanding of this very special heat exchanger, a minimum knowledge of the heat pipes is required. The heat pipe and thermosyphon basic theory (including the calculation of the thermal limits) is summarized. Some information concerning the heat pipe technological aspects is

S. Chadourne

1991-01-01

234

Numerical study of heat pipe application in heat recovery systems  

Microsoft Academic Search

Heat pipes are two-phase heat transfer devices with extremely high effective thermal conductivity. They can be cylindrical or planar in structure. Heat pipes can be embedded in a metal cooling plate, which is attached to the heat source, and can also be assembled with a fin stack for fluid heat transfer. Due to the high heat transport capacity, heat exchangers

Song Lin; John Broadbent; Ryan McGlen

2005-01-01

235

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

236

Multi-lead heat sink  

DOEpatents

The disclosure relates to a heat sink used to protect integrated circuits from the heat resulting from soldering them to circuit boards. A tubular housing contains a slidable member which engages somewhat inwardly extending connecting rods, each of which is rotatably attached at one end to the bottom of the housing. The other end of each rod is fastened to an expandable coil spring loop. As the member is pushed downward in the housing, its bottom edge engages and forces outward the connecting rods, thereby expanding the spring so that it will fit over an integrated circuit. After the device is in place, the member is slid upward and the spring contracts about the leads of the integrated circuit. Soldering is now conducted and the spring absorbs excess heat therefrom to protect the integrated circuit. The placement steps are repeated in reverse order to remove the heat sink for use again.

Roose, Lars D. (Albuquerque, NM)

1984-01-01

237

Multi-lead heat sink  

DOEpatents

The disclosure relates to a heat sink used to protect integrated circuits from the heat resulting from soldering them to circuit boards. A tubular housing contains a slidable member which engages somewhat inwardly extending connecting rods, each of which is rotatably attached at one end to the bottom of the housing. The other end of each rod is fastened to an expandable coil spring loop. As the member is pushed downward in the housing, its bottom edge engages and forces outward the connecting rods, thereby expanding the spring so that it will fit over an integrated circuit. After the device is in place, the member is slid upward and the spring contracts about the leads of the integrated circuit. Soldering is now conducted and the spring absorbs excess heat therefrom to protect the integrated circuit. The placement steps are repeated in reverse order to remove the heat sink for use again. 4 figs.

Roose, L.D.

1984-07-03

238

Multi-lead heat sink  

DOEpatents

The disclosure relates to a heat sink used to protect integrated circuits from the heat resulting from soldering them to circuit boards. A tubular housing contains a slidable member which engages somewhat inwardly extending connecting rods, each of which is rotatably attached at one end to the bottom of the housing. The other end of each rod is fastened to an expandable coil spring loop. As the member is pushed downward in the housing, its bottom edge engages and forces outward the connecting rods, thereby expanding the spring so that it will fit over an integrated circuit. After the device is in place, the member is slid upward and the spring contracts about the leads of the integrated circuit. Soldering is now conducted and the spring absorbs excess heat therefrom to protect the integrated circuit. The placement steps are repeated in reverse order to remove the heat sink for use again.

Roose, L.D.

1982-08-25

239

How Humans Adapt To Heat  

NASA Technical Reports Server (NTRS)

Report discusses adaptive responses of humans to hot environment. Describes thermoregulation by integrated responses of nervous system, vascular/fluid/electrolyte system, and endocrine system. Considers disorders resulting from failure of thermoregulation and less serious heat stress.

Greenleaf, John E.; Kaciuba-Uscilko, Hanna

1992-01-01

240

Industrial Heat Pump Case Study  

E-print Network

-up.) This concept is sometimes called mechanical vapor compression (MVC) or mechanical vapor recompression (MVR). A variety of engineering issues have to be resolved to integrate a heat pump into an evaporator system. This paper identifies key issues and describes...

Wagner, J. R.; Brush, F. C.

241

Passive heating/cooling integration for a 100 year old farmhouse  

SciTech Connect

A two story farmhouse was repaired and remodeled to withstand temperature extremes the year around by using only the natural heating/cooling of its materials and surroundings. The warmth of the earth in the crawl space keeps the plumbing from feezing in the winter. The house is ventilated by natrual flow in summer. This natural heating/cooling reduces the amount of temperature change required for comfort conditions by half or more at temperature extremes of winter or summer. At design conditions the amount of temperature change needed for comfort is moderate. Little, if any, temperature changes are required for comfort in fall and spring.

Blue, H.N.

1980-01-01

242

The secure heating reactor  

SciTech Connect

The SECURE heating reactor was designed by ASEA-ATOM as a realistic alternative for district heating in urban areas and for supplying heat to process industries. SECURE has unique safety characteristics, that are based on fundamental laws of physics. The safety does not depend on active components or operator intervention for shutdown and cooling of the reactor. The inherent safety characteristics of the plant cannot be affected by operator errors. Due to its very low environment impact, it can be sited close to heat consumers. The SECURE heating reactor has been shown to be competitive in comparison with other alternatives for heating Helsinki and Seoul. The SECURE heating reactor forms a basis for the power-producing SECURE-P reactor known as PIUS (Process Inherent Ultimate Safety), which is based on the same inherent safety principles. The thermohydraulic function and transient response have been demonstrated in a large electrically heated loop at the ASEA-ATOM laboratories.

Pind, C.

1987-11-01

243

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

244

Unsteady heat transfer in heat pipes  

NASA Astrophysics Data System (ADS)

The purpose was to investigate the unsteady heat transfer associated with a heat pipe during start up operation. Initial studies were conducted with a variety of heat pipe screen wick configurations in order to develop a mathematical expression for the flow velocity of a fluid inducted by the capillary structure of the wick. This mathematical model was solved first numerically and then simplified to provide a closed form solution. The results were compared with the experimental data and proved to provide consistent results with plus or minus 10%. A lumped parameter model of the heat pipe was next developed so that the transient operation of the heat pipe could be predicted. Upon evalaution of the model it was shown that the model and the experimental data agreed quite well in overall performance but an initial period of performance was identified where the experimental results differed significantly from the lumped parameter model. During this initial period of operation, large temperature gradients were observed, and it was theorized that the effect was a result of the interdependence of the hydrodynamics and the heat transfer characteristics of the heat pipe.

Beam, J. E.

245

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

246

Analysis of Hydrodynamics and Heat Transfer in a Thin Liquid Film Flowing over a Rotating Disk by Integral Method  

NASA Technical Reports Server (NTRS)

An integral analysis of hydrodynamics and heat transfer in a thin liquid film flowing over a rotating disk surface is presented for both constant temperature and constant heat flux boundary conditions. The model is found to capture the correct trends of the liquid film thickness variation over the disk surface and compare reasonably well with experimental results over the range of Reynolds and Rossby numbers covering both inertia and rotation dominated regimes. Nusselt number variation over the disk surface shows two types of behavior. At low rotation rates, the Nusselt number exhibits a radial decay with Nusselt number magnitudes increasing with higher inlet Reynolds number for both constant wall temperature and heat flux cases. At high rotation rates, the Nusselt number profiles exhibit a peak whose location advances radially outward with increasing film Reynolds number or inertia. The results also compare favorably with the full numerical simulation results from an earlier study as well as with the reported experimental results.

Basu, S.; Cetegen, B. M.

2005-01-01

247

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.

248

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

249

Heat flux measurements  

Microsoft Academic Search

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

Curt H. Liebert; Donald H. Weikle

1989-01-01

250

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

251

Solar heat receiver  

DOEpatents

A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

Hunt, Arlon J. (Oakland, CA); Hansen, Leif J. (Berkeley, CA); Evans, David B. (Orinda, CA)

1985-01-01

252

Heat pump with two rotors  

Microsoft Academic Search

A method and apparatus are disclosed for generating heating and cooling by circulating a working fluid within passageways carried by rotors, compressing and removing heat from the working fluid in a heat removal heat exchanger and adding heat to the working fluid in a heat addition heat exchanger, all carried by the rotors. The working fluid is sealed within, and

Eskeli

1978-01-01

253

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

254

High heat flux loop heat pipes  

NASA Technical Reports Server (NTRS)

Loop heat pipes (LHPs) can transport very large thermal power loads over long distances, through flexible, small diameter tubes against gravitational heads. In order to overcome the evaporator limit of LHPs, which is of about 0.07 MW/sq m, work was carried out to improve the efficiency by threefold to tenfold. The vapor passage geometry for the high heat flux conditions is shown. A bidisperse wick material within the circumferential vapor passages was used. Along with heat flux enhancement, several underlying issues were demonstrated, including the fabrication of bidisperse powder with controlled properties and the fabrication of a device geometry capable of replacing vapor passages with bidisperse powder.

North, Mark T.; Sarraf, David B.; Rosenfeld, John H.; Maidanik, Yuri F.; Vershinin, Sergey

1997-01-01

255

Refractory heat dry considerations  

Microsoft Academic Search

The demands of the hydrocarbon processing industry are for higher quality monolithic refractory linings. To ensure a good lining, an adequate heat dry must be performed. Unfortunately, the heat dry is often the overlooked or afterthought portion of the installation and performed in a rather haphazard manner. This article explores an actual heat dry of FCCU riser pipes lined with

1990-01-01

256

Waste heat recovery system  

Microsoft Academic Search

A waste heat recovery system for use with refrigeration means and a hot water reservoir is disclosed. The system is intended for use with refrigeration means of the type including a compressor and a condenser through which a compressible refrigerant is circulated. The system includes a heat exchanger having a refrigerant passage and a water passage mutually coupled in heat

G. W. Keller; R. J. Yaeger

1980-01-01

257

Heat exchanger support system  

Microsoft Academic Search

A mounting system to interconnect a gas turbine heat exchanger with a gas turbine includes three interconnecting gas manifolds: one to receive cool compressed air from the engine, one to receive hot exhaust gas from the engine, and one to communicate heated intake air to the engine. The manifolds, acting in cooperation with a jointed support arm, allow the heat

Young

1978-01-01

258

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

259

Heat pump modeling  

Microsoft Academic Search

Computer models of the performance of heat pumps and of individual components are described; preliminary results from system improvement studies using these models are presented. Heat exchanger models, based on a tube-by-tube computational approach, may be used by the system model when appropriate. Comparisons of calculated and observed performance parameters for heat exchangers in the laboratory are shown.

R. D. Ellison; F. A. Creswick; C. K. Rice; W. L. Jackson; S. K. Fischer

1979-01-01

260

Maximum Nighttime Urban Heat Island (UHI) Intensity Simulation by Integrating Remotely Sensed Data and Meteorological Observations  

Microsoft Academic Search

Remote sensing of the urban heat island (UHI) effect has been conducted largely through simple correlation and regression between the UHI's spatial variations and surface characteristics. Few studies have examined the surface UHI from a temporal perspective and related it with climatic and meteorological factors. By selecting the city of Beijing, China, as the study area, the purpose of this

Ji Zhou; Yunhao Chen; Jinfei Wang; Wenfeng Zhan

2011-01-01

261

A generalized boundary integral equation for isotropic heat conduction with spatially varying thermal conductivity  

Microsoft Academic Search

In this paper we derive a generalized fundamental solution for the BEM solution of problems of steady state heat conduction with arbitrarily spatially varying thermal conductivity. This is accomplished with the aid of a singular nonsymmetric generalized forcing function, D, with special sampling properties. Generalized fundamental solutions, E, are derived as locally radially symmetric responses to this nonsymmetric singular forcing

Alain J. Kassab; Eduardo Divo

1996-01-01

262

Assessment of integration of different biomass gasification alternatives in a district-heating system  

Microsoft Academic Search

With increasingly stringent CO2 emission reduction targets, incentives for efficient use of limited biomass resources increase. Technologies for gasification of biomass may then play a key role given their potential for high electrical efficiency and multiple outputs; not only electricity but also bio transport fuels and district heat. The aim of this study is to assess the economic consequences and

E. Fahlén; E. O. Ahlgren

2009-01-01

263

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

264

A corrosive resistant heat exchanger  

DOEpatents

A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

Richlen, S.L.

1987-08-10

265

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

266

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

267

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

268

"E" Heating Head  

NASA Technical Reports Server (NTRS)

Two separate areas heated inductively for adhesive bonding in single operation. "E" heating head developed to satisfy need for fast-acting and reliable induction heating device. Used in attaching "high-hat" stiffeners to aircraft panels. Incorporates principles and circuitry of toroid joining gun. Width and length configured to provide variously sized heat zones, depending on bonding requirements. Lightweight, portable and provides rapid, reliable heating of dual areas in any environment. Well suited for flight-line and depot maintenance, and battlefield repair. Also useful in automotive assembly lines to strengthen automobile panels.

Fox, Robert L.; Swaim, Robert J.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris; Copeland, Carl E.

1994-01-01

269

Industrial Waste Heat Recovery Using Heat Pipes  

E-print Network

steam to satisfy the total steam ; requirements of the refinery, such that the prim?ry boiler has been completely shut down. Eight heat pipe WHRB's are either presently: operating or being installed. In combination, they will save the equivalent... steam to satisfy the total steam ; requirements of the refinery, such that the prim?ry boiler has been completely shut down. Eight heat pipe WHRB's are either presently: operating or being installed. In combination, they will save the equivalent...

Ruch, M. A.

1981-01-01

270

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

271

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

272

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

273

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

274

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

275

Opportunities for integration of biofuel gasifiers in natural-gas combined heat-and-power plants in district-heating systems  

Microsoft Academic Search

As political pressure to improve efficiency and reduce CO2-emissions increases, natural gas combined cycle (NGCC) combined heat-and-power (CHP) technology is an increasingly attractive option for district-heating systems. However, as CO2-emissions reduction targets become more ambitious, it is expected that there will be pressure to reduce CO2-emissions from such units well before they reach the end of their useful lifetime. One

Åsa Marbe; Simon Harvey

2006-01-01

276

Optimal design of the separate type heat pipe heat exchanger  

Microsoft Academic Search

Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger\\u000a conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing\\u000a an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations\\u000a have to

Zi-tao Yu; Ya-cai Hu; Ke-fa Cen

2005-01-01

277

Absorption heat pumps  

NASA Astrophysics Data System (ADS)

The aim of the study was to analyze the technical and economic feasibility of absorption heat pumps in Finland. The work was done as a case study: the technical and economic analyses have been carried out for six different cases, where in each the suitable size and type of the heat pump plant and the auxiliary components and connections were specified. The study also detailed the costs concerning the procurement, installation and test runs of the machinery, as well as the savings in energy costs incurred by the introduction of the plant. Conclusions were drawn of the economic viability of the applications studied. The following cases were analyzed: heat recovery from flue gases and productin of district heat in plants using peat, natural gas, and municipal wastes as a fuel. Heat recovery in the pulp and paper industry for the upgrading of pressure of secondary steam and for the heating of white liquor and combustion and drying the air. Heat recovery in a peat-fulled heat and power plant from flue gases that have been used for the drying of peat. According to the study, the absorption heat pump suits best to the production of district heat, when the heat source is the primary energy is steam produced by the boiler. Included in the flue as condensing is the purification of flue gases. Accordingly, benefit is gained on two levels in thick applications. In heat and power plants the use of absorption heat pumps is less economical, due to the fact that the steam used by the pump reduces the production of electricity, which is rated clearly higher than heat.

Huhtinen, M.; Heikkilae, M.; Andersson, R.

1987-03-01

278

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

279

Heat Flux Determination From Measured Heating Rates Using Thermographic Phosphors  

Microsoft Academic Search

A new method for measuring the heating rate (defined as the time rate of change of temperature) and estimating heat flux from the heating rate is proposed. The example problem involves analytic heat conduction in a one-dimensional slab, where the measure- ment location of temperature or heating rate coincides with the location of the estimated heat flux. The new method

D. G. Walker

2005-01-01

280

A networked heat meter system for measuring domestic heat supply  

Microsoft Academic Search

Heat meter is playing an increasing important role in district heating system as a basic heat measurement device. The objective of this paper is to design a novel networked heat meter with high stability and measurement accuracy for domestic water heating system and an experimental computer management system of the heat meter for remote data acquisition and management automation. Firstly,

Xianming Ye; Xiaodong Zhang; Weifeng Diao

2005-01-01

281

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP  

E-print Network

the attractiveness of the present concept. SYSTEM DESCRIPTION The heat activated heat pump (HAHP) employs a primePERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. C. Richards and W. L. Auxer General Electric Company Space Division King of Prussia, Pa. ABSTRACT A heat activated heat pump (HAHP

Oak Ridge National Laboratory

282

Local heat transfer process and pressure drop in a micro-channel integrated with arrays of temperature and pressure sensors  

Microsoft Academic Search

One of the most important components in micro-fluidic system is the micro-channel which involves complicated flow and transport\\u000a process. This study presents micro-scale thermal fluid transport process inside a micro-channel with a height of 37 ?m. The\\u000a channel can be heated on the bottom wall and is integrated with arrays of pressure and temperature sensors which can be used\\u000a to measure

H. S. Ko; C. Gau

2011-01-01

283

Estimation of non-linear continuous time models for the heat exchange dynamics of building integrated photovoltaic modules  

Microsoft Academic Search

This paper focuses on a method for linear or non-linear continuous time modelling of physical systems using discrete time data. This approach facilitates a more appropriate modelling of more realistic non-linear systems. Particularly concerning advanced building components, convective and radiative heat interchanges are non-linear effects and represent significant contributions in a variety of components such as photovoltaic integrated façades or

M. J. Jiménez; H. Madsen; J. J. Bloem; B. Dammann

2008-01-01

284

Process-integration methodology for natural-gas-fueled heat pumps and cogeneration systems. Final report, March 1987October 1988  

Microsoft Academic Search

The objective of the project was to develop a process-integration methodology for analyzing industrial processes, identifying those that will benefit from natural-gas-fueled heat pumps and cogeneration system as well as novel, process-specific opportunities for further equipment improvements, including performance targets. The development included the writing of software to assist in implementing the methodology and application of the procedures in studies

Rossiter

1988-01-01

285

Heat stroke and cytokines.  

PubMed

Heat stroke is a life-threatening illness that affects all segments of society, including the young, aged, sick, and healthy. The recent high death toll in France (Dorozynski, 2003) and the death of high-profile athletes has increased public awareness of the adverse effects of heat injury. However, the etiology of the long-term consequences of this syndrome remains poorly understood such that preventive/treatment strategies are needed to mitigate its debilitating effects. Cytokines are important modulators of the acute phase response (APR) to stress, infection, and inflammation. Current data implicating cytokines in heat stroke responses are mainly from correlation studies showing elevated plasma levels in heat stroke patients and experimental animal models. Correlation data fall far short of revealing the mechanisms of cytokine actions such that additional research to determine the role of these endogenous substances in the heat stroke syndrome is required. Furthermore, cytokine determinations have occurred mainly at end-stage heat stroke, such that the role of these substances in progression and long-term recovery is poorly understood. Despite several studies implicating cytokines in heat stroke pathophysiology, few studies have examined the protective effect(s) of cytokine antagonism on the morbidity and mortality of heat stroke. This is particularly surprising since heat stroke responses resemble those observed in the endotoxemic syndrome, for which a role for endogenous cytokines has been strongly implicated. The implication of cytokines as mediators of endotoxemia and the presence of circulating endotoxin in heat stroke patients suggests that much knowledge can be gained from applying our current understanding of endotoxemic pathophysiology to the study of heat stroke. Heat shock proteins (HSPs) are highly conserved proteins that function as molecular chaperones for denatured proteins and reciprocally modulate cytokine production in response to stressful stimuli. HSPs have been shown repeatedly to confer protection in heat stroke and injury models. Interactions between HSPs and cytokines have received considerable attention in the literature within the last decade such that a complex pathway of interactions between cytokines, HSPs, and endotoxin is thought to be occurring in vivo in the orchestration of the APR to heat injury. These data suggest that much of the pathophysiologic changes observed with heat stroke are not a consequence of heat exposure, per se, but are representative of interactions among these three (and presumably additional) components of the innate immune response. This chapter will provide an overview of current knowledge regarding cytokine, HSP, and endotoxin interactions in heat stroke pathophysiology. Insight is provided into the potential therapeutic benefit of cytokine neutralization for mitigation of heat stroke morbidity and mortality based on our current understanding of their role in this syndrome. PMID:17645934

Leon, Lisa R

2007-01-01

286

Assessment of combined heat and power (CHP) integrated with wood-based ethanol production  

Microsoft Academic Search

A techno-economic assessment is made of wood-based production of ethanol, where the by-products are used for internal energy needs as well as for generation of electricity, district heat and pelletised fuel in different proportions for external use. Resulting ethanol production costs do not differ much between the options but a process where electricity generation is maximised by use of the

Gunnar Eriksson; Björn Kjellström

2010-01-01

287

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 Icing 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 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 and the future flight unit are considered.

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

2012-01-01

288

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

289

Heat pump system  

DOEpatents

An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

Swenson, Paul F. (Shaker Heights, OH); Moore, Paul B. (Fedhaven, FL)

1983-01-01

290

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

291

Plasma heat pump and heat engine  

SciTech Connect

A model system where cold charged particles are locally confined in a volume V{sub P} within a warm plasma of volume V (V{sub P}<heat and vice versa. Two applications of this theory are, first we propose a pumping device which heats plasmas by an adiabatic/isothermal compression of fields. Heating power ranging from a few hundred watts to a few kilowatts is possible with the present day technology. Second, we discuss the feasibility of constructing an electrostatic heat engine which converts plasma heat into mechanical work via plasma electric fields. Effects of P{sub E} are shown to be observable in colloidal solutions.

Avinash, K. [Centre for Space Plasma and Aeronomic Research, University of Alabama, Huntsville, Alabama 35899 (United States) and Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

2010-08-15

292

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

293

Heat pipe turbine vane cooling  

Microsoft Academic Search

The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high

L. Langston; A. Faghri

1995-01-01

294

Heat fluctuations and initial ensembles  

NASA Astrophysics Data System (ADS)

Time-integrated quantities such as work and heat increase incessantly in time during nonequilibrium processes near steady states. In the long-time limit, the average values of work and heat become asymptotically equivalent to each other, since they only differ by a finite energy change in average. However, the fluctuation theorem (FT) for the heat is found not to hold with the equilibrium initial ensemble, while the FT for the work holds. This reveals an intriguing effect of everlasting initial memory stored in rare events. We revisit the problem of a Brownian particle in a harmonic potential dragged with a constant velocity, which is in contact with a thermal reservoir. The heat and work fluctuations are investigated with initial Boltzmann ensembles at temperatures generally different from the reservoir temperature. We find that, in the infinite-time limit, the FT for the work is fully recovered for arbitrary initial temperatures, while the heat fluctuations significantly deviate from the FT characteristics except for the infinite initial-temperature limit (a uniform initial ensemble). Furthermore, we succeed in calculating finite-time corrections to the heat and work distributions analytically, using the modified saddle point integral method recently developed by us. Interestingly, we find noncommutativity between the infinite-time limit and the infinite-initial-temperature limit for the probability distribution function (PDF) of the heat.

Kim, Kwangmoo; Kwon, Chulan; Park, Hyunggyu

2014-09-01

295

Reduction of Peak Heat Fluxes by Supplying Heat to the Free Stream  

Microsoft Academic Search

A supersonic flow past a blunt body in the presence of an incident oblique shock wave is considered. It is shown that by supplying heat to the free stream it is possible substantially to reduce local heat flux peaks on the body surface. The integral heat flux on the body surface increases by only a small fraction of the heat

M. N. Kogan; M. A. Starodubtsev

2003-01-01

296

Optimization of cross flow heat exchangers for thermoelectric waste heat recovery  

Microsoft Academic Search

Thermoelectric waste heat recovery is investigated for current thermoelectric materials with advanced heat exchangers. Numerical heat exchanger models integrated with models for Bi2Te3 thermoelectric modules are validated against experimental data from previous cross flow heat exchanger studies as well as experiments using thermoelectrics between counterflow hot water and cooling air flow channels. The models are used in optimization studies of

Douglas T. Crane; Gregory S. Jackson

2004-01-01

297

Influence of the mechanical stress and heat parameters into the transmittance function of the integrals of the diffraction phenomena  

NASA Astrophysics Data System (ADS)

For the diffraction equations for the exact and convolutions Fourier's integrals, the parameters related with mechanical stress and heat are introduced into the mathematical function of the transmittance t0(x0,y0). Taking into account the new transmittance equation, a new set of equations for the exact and convolution Fourier's integrals have been derived. The only restriction for the analysis done is that for the apertures under study, they are only on a plane. An example af an experiment where a diffraction aperture suffers of a mechanical stress is shown.

Andrés-Zárate, Esteban; Cornejo-Rodríguez, Alejandro

2011-09-01

298

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

299

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

300

TechLab: Canned Heat  

NSDL National Science Digital Library

This inquiry-based classroom lab investigates of the nature of heating and cooling by thermal absorption and emission. Using temperature probes connected to computer USB interfaces, the students examine the effects of radiant heat on three metal cans of varying colors. The lesson plan is detailed and thorough, giving explanations of how to use computer tools to graph results of the experiment. The lab is a true integration of technology and physics education.

Baird, Dean

2006-07-18

301

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,

302

Counterflow Regolith Heat Exchanger  

NASA Technical Reports Server (NTRS)

A problem exists in reducing the total heating power required to extract oxygen from lunar regolith. All such processes require heating a great deal of soil, and the heat energy is wasted if it cannot be recycled from processed material back into new material. The counterflow regolith heat exchanger (CoRHE) is a device that transfers heat from hot regolith to cold regolith. The CoRHE is essentially a tube-in-tube heat exchanger with internal and external augers attached to the inner rotating tube to move the regolith. Hot regolith in the outer tube is moved in one direction by a right-hand - ed auger, and the cool regolith in the inner tube is moved in the opposite direction by a left-handed auger attached to the inside of the rotating tube. In this counterflow arrangement, a large fraction of the heat from the expended regolith is transferred to the new regolith. The spent regolith leaves the heat exchanger close to the temperature of the cold new regolith, and the new regolith is pre-heated close to the initial temperature of the spent regolith. Using the CoRHE can reduce the heating requirement of a lunar ISRU system by 80%, reducing the total power consumption by a factor of two. The unique feature of this system is that it allows for counterflow heat exchange to occur between solids, instead of liquids or gases, as is commonly done. In addition, in variants of this concept, the hydrogen reduction can be made to occur within the counterflow heat exchanger itself, enabling a simplified lunar ISRU (in situ resource utilization) system with excellent energy economy and continuous nonbatch mode operation.

Zubrin, Robert; Jonscher, Peter

2013-01-01

303

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

304

Boiling heat transfer in compact heat exchangers  

SciTech Connect

Small circular and noncircular channels are representative of flow passages in compact evaporators and condensers. This paper describes results of an experimental study on heat transfer to the flow boiling of refrigerant- 12 in a small circular tube of diameter = 2.46 mm. The objective of the study was to assess the effect of channel size on the heat transfer coefficient and to obtain additional insights relative to the heat transfer mechanisms. The flow channel was made of brass and had an overall length of 0.9 m. The channel wall was electrically heated, and temperatures were measured on the channel wall and in the bulk fluid stream. Voltage taps were located at the same axial locations as the stream thermocouples to allow testing over an exit quality range of 0.21 to 0.94 and a large range of mass flux (63 to 832 kg/m{sup 2}s) and heat flux (2.5 to 59 kW/m{sup 2}). Saturation pressure was nearly constant, averaging 0.82 MPa for most of the testing; a few test data were also taken at a constant lower pressure of 0.52 MPa. Local heat transfer coefficients were determined experimentally. Analysis provided additional support for the conclusion, arrived at from previous studies, that a nucleation mechanism dominates for flow boiling in small channels; nevertheless, a convective-dominant region was identified at very low values of wall superheat (<{approx}3{degrees}C). Previous flow boiling studies in small channels, that did not include wall superheats this low, did not encounter the convective dominant mechanism. Conversely, cryogenic studies at very low wall superheats ({approx}l{degree}C) did not encounter the nucleation dominant regime. The apparent discrepancy is explained by the results of this study.

Tran, T.N.; Wambsganss, M.W. [Argonne National Lab., IL (United States); France, D.M. [Illinois Univ., Chicago, IL (United States). Dept. of Mechanical Engineering

1994-12-31

305

Specific heat of HMX  

SciTech Connect

The specific heat of octahydro-1,3,5, 7-tetranitro-1,3,5,7 tetrazocine (HMX) was determined by the use of a differential scanning calorimeter (DSC). The specific heat for both crystalline and powdered samples was obtained from 294 to 445 K for the beta phase and from 410 to 485 K for the delta phase. The specific heat results were fitted to least squares polynomials to allow the interpolation of the data between points and extrapolation with appropriate care to higher temperatures. The effects of partially decomposed HMX samples on the specific heat were investigated also. 6 references.

Koshigoe, L.G.; Shoemaker, R.L.

1984-11-01

306

Heat Pipe Materials Compatibility  

NASA Technical Reports Server (NTRS)

An experimental program to evaluate noncondensable gas generation in ammonia heat pipes was completed. A total of 37 heat pipes made of aluminum, stainless steel and combinations of these materials were processed by various techniques, operated at different temperatures and tested at low temperature to quantitatively determine gas generation rates. In order of increasing stability are aluminum/stainless combination, all aluminum and all stainless heat pipes. One interesting result is the identification of intentionally introduced water in the ammonia during a reflux step as a means of surface passivation to reduce gas generation in stainless-steel/aluminum heat pipes.

Eninger, J. E.; Fleischman, G. L.; Luedke, E. E.

1976-01-01

307

Space heating technology atlas  

SciTech Connect

An extensive review of heating plants, from in-space heaters, furnaces, heat pumps, and boilers, to woodstoves, and fireplaces -- with emphasis on whole-building optimization -- is the cornerstone of this Atlas. Discussion of the interaction of human behavior, productivity, and comfort with space conditioning systems, end-use and market trends, codes and standards, and reducing heating loads through passive solar and state-of-the-art insulation, windows, sealing, and construction systems are included. Heat distribution systems and residential mechanical ventilation are also discussed in detail. The resources section offers thorough lists of manufacturers and trade and professional organizations, a glossary, and an index.

NONE

1993-12-31

308

Reclaiming Waste Heat  

NASA Technical Reports Server (NTRS)

'Air-O-Space' heater, based on spacecraft heat, requires no fuel other than electricity to run fan. Installed in chimney flue, heat pipes transfer heat from waste hot gases (but not the gases themselves) to fresh air blown across the other end of the pipes. It can transport roughly 500 times the heat flux of the best solid conductors with a temperature drop of less than 3 degrees per foot. This instrument has also been used by Kin-Tek Laboratories Inc. to produce an instrument to calibrate gas analyzers for air-pollution monitoring.

1976-01-01

309

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

310

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

311

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

312

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

313

Waste heat recovery using heat pipe heat exchanger (HPHE) for surgery rooms in hospitals  

Microsoft Academic Search

Research has been carried out on the theory, design and construction of heat pipes, especially their use in heat pipe heat exchangers for energy recovery, reduction of air pollution and environmental conservation. A heat pipe heat exchanger has been designed and constructed for heat recovery in hospital and laboratories, where the air must be changed up to 40 times per

S. H. Noie-Baghban; G. R. Majideian

2000-01-01

314

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

315

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

316

Lunar Base Heat Pump  

NASA Technical Reports Server (NTRS)

The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

Walker, D.; Fischbach, D.; Tetreault, R.

1996-01-01

317

THERMOCHEMICAL HEAT STORAGE FOR CONCENTRATED; SOLAR POWER  

Microsoft Academic Search

Thermal energy storage (TES) is an integral part of a concentrated solar power (CSP) system. It enables plant operators to generate electricity beyond on sun hours and supply power to the grid to meet peak demand. Current CSP sensible heat storage systems employ molten salts as both the heat transfer fluid and the heat storage media. These systems have an

2011-01-01

318

Heat hyperalgesiaHeat hyperalgesia TIME (days)  

E-print Network

and to sham animals. Thermal hyperalgesia, as assessed on Plantar test, was much smaller in SNI than CCI rats) and sham (n = 8). Adult mice (n=6) were also used. � Pain behavioral testing All operated animals (CCI, SNI is standing, is quickly heated up to the desired temperature, the animal avoids the noxious stimulus typically

Apkarian, A. Vania

319

Performance Evaluation of Heat Pipe Heat Exchanger  

Microsoft Academic Search

To the basis of first law of thermodynamics, mainly applicable to engineering calculations; to the basis of the second law of thermodynamics - entropy analysis method, can be used to apply to theoretical analysis and engineering calculations. In this paper, a single performance valuation and entropy analysis for heat recovery equipment have been used, which is to make performance evaluation

Zhang Jie; Ren Yan; Zhang Li Hong; Zhang Kang

2010-01-01

320

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

321

Waste heating recovery system  

Microsoft Academic Search

An apparatus is described for recovering waste heat from a refrigeration system having a compressor, condensor and evaporator coupled together for circulating a refrigerant comprising: heat exchanger means adapted to be connected to the system between the compressor and condensor and having an inlet for receiving the refrigerant from the compressor and an outlet for supplying the refrigerant to the

E. M. Richardson; T. P. Sim

1987-01-01

322

The district heating renaissance  

SciTech Connect

This article examines the expanding market for district heating and cooling systems as part of independent cogeneration systems. The topics of the article include expanding systems, future potential, government help, cogeneration, district cooling expanding, absorption chilling, indoor air quality, and institutional barriers to the expanding market. The article also includes a sidebar on Denmark's district heating systems.

Seeley, R.S.

1992-09-01

323

Heat Storage Duration.  

National Technical Information Service (NTIS)

Both the amount and duration of heat storage in massive elements of a passive building are investigated. Data taken for one full winter in the Balcomb solar home are analyzed with the aid of sub-system simulation models. Heat storage duration is tallied i...

J. D. Balcomb

1981-01-01

324

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

325

Gyrokinetic turbulent heating  

SciTech Connect

Expressions for particle and energy fluxes and heating rates due to turbulence are derived. These fluxes and heating rates are identified from moments of an extended drift-kinetic equation for the equilibrium distribution function. These include neoclassical as well as turbulent diffusion and heating. Phase-space conservation is demonstrated, allowing the drift-kinetic equation to be expressed in conservative form. This facilitates taking moments with few approximations, mainly those consistent with drift kinetics for the equilibrium distribution function and the relative smallness of the fluctuations. The turbulent heating is uniquely defined by choosing the standard gyrokinetic definition for the energy flux. With this definition, most of the heating can be expressed in the form of ohmic heating from turbulent parallel and perpendicular current density perturbations. The latter current is identified with grad-B and curvature drifts, plus terms involving magnetic perturbations (which are smaller for low beta). A small contribution to the heating comes from the divergence of an energy flux that is dependent on the finite gyroradius of the ions. The fluxes and heating rates are expressed in a form that can be easily evaluated from gyrokinetic turbulence simulations.

Hinton, F. L.; Waltz, R. E. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

2006-10-15

326

Solar heating right now  

Microsoft Academic Search

Mr. Edgerton states that solar systems operating today can provide 50 to 75 percent of the heat for new houses; that for $2,000 to $6,000, solar heating can be built into a new house, and savings of oil, gas, or electricity will often pay off this investment within ten years. More elaborate systems employing advanced technology can cost up to

1976-01-01

327

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

328

Blowdown heat recovery systems  

Microsoft Academic Search

Proper installation and use of simple, inexpensive blowdown heat recovery systems can save more than 80 percent of the energy contained in hot water that is often discharged into the sewer. Many plants use blowdown heat recovery systems to increase boiler efficiency; however, there are some operating difficulties associated with the equipment installation. This article discusses blowdown calculations, how to

1984-01-01

329

Heat flux sensor calibrator  

Microsoft Academic Search

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

C. H. Liebert

1985-01-01

330

Basic Comfort Heating Principles.  

ERIC Educational Resources Information Center

The material in this beginning book for vocational students presents fundamental principles needed to understand the heating aspect of the sheet metal trade and supplies practical experience to the student so that he may become familiar with the process of determining heat loss for average structures. Six areas covered are: (1) Background…

Dempster, Chalmer T.

331

Heat Shield in Pieces  

NASA Technical Reports Server (NTRS)

This image from NASA's Mars Exploration Rover Opportunity shows the remains of the rover's heat shield, broken into two key pieces, the main piece on the left side and a broken-off flank piece near the middle of the image. The heat shield impact site is identified by the circle of red dust on the right side of the picture. In this view, Opportunity is approximately 20 meters (66 feet) away from the heat shield, which protected it while hurtling through the martian atmosphere.

In the far left of the image, a meteorite called 'Heat Shield Rock,' sits nearby, The Sun is reflecting off the silver-colored underside of the internal thermal blankets of the heat shield.

The rover spent 36 sols investigating how the severe heating during entry through the atmosphere affected the heat shield. The most obvious is the fact that the heat shield inverted upon impact.

This is an approximately true-color rendering of the scene acquired around 1:22 p.m. local solar time on Opportunity sol 324 (Dec. 21, 2004) in an image mosaic using panoramic filters at wavelengths of 750, 530, and 430 nanometers.

2005-01-01

332

Solar heating panel  

Microsoft Academic Search

A solar heating panel with a heat collector mounted on an insulating base and an arched cover over said collector mounted in clips at the edges of the base is described. One or two flexible covers slidingly positioned in channels of the mounting clips, with a cover in sealing engagement with the insulating base and projecting downward below the top

1976-01-01

333

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

334

Waste heat recovery system  

Microsoft Academic Search

A heat recovery system for use with a rotatable cylindrical kiln having a curved sidewall surface and which is adapted to be fired, for example, by a burner supplied through a fuel supply line with fuel oil, comprises, at least one segment member which overlies and is spaced from the kiln curved sidewall surface and which defines a heat radiation

Euskirchen

1980-01-01

335

Passive Vaporizing Heat Sink  

NASA Technical Reports Server (NTRS)

A passive vaporizing heat sink has been developed as a relatively lightweight, compact alternative to related prior heat sinks based, variously, on evaporation of sprayed liquids or on sublimation of solids. This heat sink is designed for short-term dissipation of a large amount of heat and was originally intended for use in regulating the temperature of spacecraft equipment during launch or re-entry. It could also be useful in a terrestrial setting in which there is a requirement for a lightweight, compact means of short-term cooling. This heat sink includes a hermetic package closed with a pressure-relief valve and containing an expendable and rechargeable coolant liquid (e.g., water) and a conductive carbon-fiber wick. The vapor of the liquid escapes when the temperature exceeds the boiling point corresponding to the vapor pressure determined by the setting of the pressure-relief valve. The great advantage of this heat sink over a melting-paraffin or similar phase-change heat sink of equal capacity is that by virtue of the =10x greater latent heat of vaporization, a coolant-liquid volume equal to =1/10 of the paraffin volume can suffice.

Knowles, TImothy R.; Ashford, Victor A.; Carpenter, Michael G.; Bier, Thomas M.

2011-01-01

336

Heat and Motion.  

ERIC Educational Resources Information Center

Unlike many elementary presentations on heat, this monograph is not restricted to explaining thermal behavior in only macroscopic terms, but also developes the relationships between thermal properties and atomic behavior. "It relies at the start on intuition about heat at the macroscopic level. Familiarity with the particle model of mechanics,…

Pearlman, Norman

337

Heating by wind  

Microsoft Academic Search

The economical design of a wind power plant combined with a heat accumulator is discussed. A gliding-museum to be built on the Wasserkuppe in the Rhoen mountain is used as an example to investigate which wind power plant and storage alternative can be considered based on meteorological basic data and the heat demand required. A system optimization regarding technical and

F. Auer

1982-01-01

338

Heating and ventilation system  

Microsoft Academic Search

A system is described for controlling the temperature, ventilation, illumination, and humidity within an enclosed building having at least one wall exposed to solar radiation comprising: a double glazed window mounted on the wall; means for measuring the net heat energy flow through the window; means for automatically adjusting the heat energy flow; means provided for absorbing at least a

1974-01-01

339

Acoustic Heating Peter Ulmschneider  

E-print Network

Acoustic Heating Peter Ulmschneider lnstitut fiir Theoretische Astrophysik der Universitat Heidelberg Im Neuenheimer Feld 561, 6900 Heidelberg 1, Federal Republic of Germany. Abstract. Acoustic shock waves are a viable and prevalent heating mechanism both in early- and in late-type stars. Acoustic

Ulmschneider, Peter

340

Design and Analysis of High-Performance Air-Cooled Heat Exchanger with an Integrated Capillary-Pumped Loop Heat Pipe  

E-print Network

We report the design and analysis of a high-power air-cooled heat exchanger capable of dissipating over 1000 W with 33 W of input electrical power and an overall thermal resistance of less than 0.05 K/W. The novelty of the ...

McCarthy, Matthew

341

Thermodynamic analysis of chemical heat storage system for heat pump  

Microsoft Academic Search

In order to establish a performance index of chemical heat storage, a method of assessment was proposed wherein the action principles were adjusted as well as the examples of the application. In a chemical heat storage system wherein the exhaust heat at heat storage operation and the driving heat source at the exothermic operation and the compressor power are utilized,

Michiyuki Saikawa; Tetsushiro Iwatsubo; Teruhide Hamamatsu

1987-01-01

342

PreHeat: Controlling Home Heating Using Occupancy Prediction  

E-print Network

heating. We deployed PreHeat in five homes, three in the US and two in the UK. In UK homes, we controlled heating on a per-room basis to enable further energy savings. We compared PreHeat's prediction algorithm, and measuring actual gas consumption and occupancy. In UK homes PreHeat both saved gas and reduced MissTime (the

Krumm, John

343

HEAT CONDUCTION NETWORKS: DISPOSITION OF HEAT BATHS AND INVARIANT MEASURE  

E-print Network

HEAT CONDUCTION NETWORKS: DISPOSITION OF HEAT BATHS AND INVARIANT MEASURE ALAIN CAMANES Abstract linking existence and uniqueness of the invariant measure to the disposition of the heat baths. We consider a model of heat conduction networks consisting of oscillators in contact with heat baths

Paris-Sud XI, Université de

344

A method of analysis for heat pipe heat exchangers  

Microsoft Academic Search

A method of analysis for the thermal performance of heat pipe heat exchangers based on the conductance model was developed in the present study. In the analysis the specific heat conductance of the heat pipe was obtained from a performance test of a single heat pipe described in the present paper and the well-known universal correlations were used to calculate

B. J. Huang; J. T. Tsuei

1985-01-01

345

Experimental investigation of a manifold heat-pipe heat exchanger  

Microsoft Academic Search

Results of experimental investigations of a heat exchanger on a manifold water heat pipe are given. An analysis is made of the temperature distribution along the heat-transfer agent path as a function of the transferred heat power. The influence of the degree of filling with the heat transfer agent on the operating characteristics of the construction is considered.

S. V. Konev

1995-01-01

346

Heat pipe heat exchangers as energy recovery devices  

Microsoft Academic Search

Counterflow heat exchangers comprised of a bundle of heat pipes with secondary finned surfaces attached offer attractive advantages as energy recovery units. With no moving parts and wide design flexibility, these heat pipe heat exchangers are finding ever increasing usage in air-to-air heat recovery. Three general classes of applications can be identified: using energy recovery from process exhaust to regenerate

Ruch

1976-01-01

347

Preliminary design study of heat pipe heat exchangers  

Microsoft Academic Search

A preliminary design study was conducted in order to identify the important design parameters which can be varied to optimize overall performance of heat pipe heat exchangers. A computer program was developed to analyze the heat exchanger performance using conventional design procedures for finned tube heat exchangers and using conventional design procedures for three-puddle-artery heat pipes.

K. T. Feldman; D. C. Lu

1976-01-01

348

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.

349

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

350

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

351

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

352

The Chemical Heat Pump Program. An overview  

NASA Astrophysics Data System (ADS)

A brief overview of the Chemical Heat Pump Program is presented. Program background, rationale, technology description, and research and development needs are addressed. Chemical heat pumps comprise reversible reactions which can be driven by low grade heat. Thermal energy is absorbed in one direction and librated in the reverse direction: thus, serving as a basis for system designs applicable to space conditioning or process heat management and offering the capability for high density energy storage as an integral part of the system.

Mezzina, A.

1982-03-01

353

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

354

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

355

Waste heat recovery system controller  

Microsoft Academic Search

In a system having a waste heat recovery subsystem utilizing a heat exchanger, such as a refrigeration system having a heat exchanger for extracting and recovering heat energy from the superheated refrigerant by means of a transfer fluid, a method and apparatus for control of the heat recovery subsystem are described. A combination of three interactive control systems is provided

1980-01-01

356

Heating buildings with solar energy  

Microsoft Academic Search

A general description of a solar heating system used for room heating, cooking, water heating, drying clothes, and electrical consumption for cooling and heating, is given. A degree day analysis for Gainesville, Florida, indicated that the solar heating system would consume 126 kWh of electricity during the winter months, giving a 92% reduction of energy consumption when compared to a

E. A. Farber; C. A. Morrison; H. A. Ingley; F. J. Tarud

1975-01-01

357

Geothermal Heat Transfer  

SciTech Connect

This patent describes a heat transfer apparatus which consists of: heat exchanging means for orientation in the earth below ground substantially vertically, having a hollow conduit of length from top to bottom much greater than the span across the hollow conduit orthogonal to its length with a top, bottom and an intermediate portion contiguous and communicating with the top and bottom portions for allowing thermally conductive fluid to flow freely between the top, intermediate and bottom portions for immersion in thermally conductive fluid in the region around the heat exchanging means for increasing the heat flow between the latter and earth when inserted into a substantially vertical borehole in the earth with the top portion above the bottom portion. The heat exchanger consists of heat exchanging conduit means in the intermediate portion for carrying refrigerant. The heat exchanging conduit consisting of tubes of thermally conductive material for carrying the refrigerant and extending along the length of the hollow conduit for a tube length that is less than the length of the hollow conduit. The hollow conduit is formed with port means between the top and the plurality of tubes for allowing the thermally conductive fluid to pass in a flow path embracing the tubes, the bottom portion, an outer channel around the hollow conduit and the port means.

Basmajian, V.V.

1986-01-28

358

Heat pipe dynamic behavior  

NASA Technical Reports Server (NTRS)

The vapor flow in a heat pipe was mathematically modeled and the equations governing the transient behavior of the core were solved numerically. The modeled vapor flow is transient, axisymmetric (or two-dimensional) compressible viscous flow in a closed chamber. The two methods of solution are described. The more promising method failed (a mixed Galerkin finite difference method) whereas a more common finite difference method was successful. Preliminary results are presented showing that multi-dimensional flows need to be treated. A model of the liquid phase of a high temperature heat pipe was developed. The model is intended to be coupled to a vapor phase model for the complete solution of the heat pipe problem. The mathematical equations are formulated consistent with physical processes while allowing a computationally efficient solution. The model simulates time dependent characteristics of concern to the liquid phase including input phase change, output heat fluxes, liquid temperatures, container temperatures, liquid velocities, and liquid pressure. Preliminary results were obtained for two heat pipe startup cases. The heat pipe studied used lithium as the working fluid and an annular wick configuration. Recommendations for implementation based on the results obtained are presented. Experimental studies were initiated using a rectangular heat pipe. Both twin beam laser holography and laser Doppler anemometry were investigated. Preliminary experiments were completed and results are reported.

Issacci, F.; Roche, G. L.; Klein, D. B.; Catton, I.

1988-01-01

359

Research Note on a Parabolic Heat-Balance Integral Method with Unspecified Exponent: An Entropy Generation Approach in Optimal Profile Determination  

E-print Network

The heat-balance integral method of Goodman is studied with two simple 1-D heat conduction problems with prescribed temperature and flux boundary conditions. These classical problems with well known exact solutions enable to demonstrate the heat-balance integral method performance by a parabolic profile and the entropy generation minimization concept in definition of the appropriate profile exponent. The basic assumption generating the additional constraints needed to perform the solution is based on the requirement to minimize the difference in the local thermal entropy generation rates calculated by the approximate and the exact profile, respectively. This concept is easily applicable since the general concept has simple implementation of the condition requiring the thermal entropy generations calculated through both profiles to be the same at the boundary. The entropy minimization generation approach automatically generates the additional requirement which is deficient in the set of conditions defined by the heat-balance integral method concept.

Jordan Hristov

2010-12-12

360

PreHeat: controlling home heating using occupancy prediction  

Microsoft Academic Search

Home heating is a major factor in worldwide energy use. Our system, PreHeat, aims to more efficiently heat homes by using occupancy sensing and occupancy prediction to automatically control home heating. We deployed PreHeat in five homes, three in the US and two in the UK. In UK homes, we controlled heating on a per-room basis to enable further energy

James Scott; A. J. Bernheim Brush; John Krumm; Brian Meyers; Michael Hazas; Stephen Hodges; Nicolas Villar

2011-01-01

361

Analysis and application of the heat pipe heat exchanger  

Microsoft Academic Search

Heat pipe heat exchangers offer many advantages over more conventional heat exchangers, particularly for gas-to-gas application. Proper application of these devices depends on the conditions imposed by the process from which waste heat is to be recovered, and some of the more common constraints are analyzed. The overall operation of heat pipe heat exchangers is best studied using effectiveness-NTU calculations,

T. H. Sun; R. C. Prager

1978-01-01

362

Progress in heat pipe and porous heat exchanger technology  

Microsoft Academic Search

This is a review of the papers presented at the 1st International Heat Pipe Conference held in Stuttgart, 15-17 October 1973. The review deals with heat pipe application in different branches of technology, heat- and mass-transfer processes in heat pipes, design of variable-conductance heat pipes, optimization of their parameters, operation of heat pipes under weightlessness and in the field of

A. V. Luikov; L. L. Vasiliev

1975-01-01

363

Sterilization by dry heat  

PubMed Central

The advantages and disadvantages of three forms of dry heat sterilization are discussed. In addition a fourth method, consisting of heating by infrared rays in vacuo, is described. This method is particularly suitable for instruments used in the operating theatre, since it can replace an autoclave where a supply of steam is not available. Recommended times and temperatures for dry heat sterilization are detailed, and are related to the thermal death point of Cl. tetani. The dangers of recontamination during the cooling process are discussed. PMID:13719782

Darmady, E. M.; Hughes, K. E. A.; Jones, J. D.; Prince, D.; Tuke, Winifred

1961-01-01

364

Space heating installation  

SciTech Connect

A description is given of a heat pump comprising a compressor having a rotatable casing and a rotatable impeller; a liquid heat exchanger and an air heat exchanger combined with said rotatable casing to form a rotatable unit; a bearing rotatably mounting said rotatable unit with the center of gravity of said unit being located above said bearing; a magnetically active rotor connected to said impeller; a stator spaced from and providing a drive torque to said rotor whereby when said rotor is rotated, said unit will rotate by the reaction moment of said impeller; and a magnetically pervous separation wall situated between said stator and said rotor.

Laing, K.; Laing, N.; Laing, O.; Ludin, L.

1980-07-08

365

Translating wedge heat sink  

NASA Astrophysics Data System (ADS)

This patent application discloses a device for dissipating heat from cased electronics where optimum heat transfer is required, and easy removability is desired. The device finds utility in sonobuoys, buoys, missiles and mines, as well as cabling electronics such as transoceanic communications equipment. The device contains a translating wedge which is drawn into a forced fit between the heat generating module and a conducting wedge which contacts the electronics case, resulting in a high efficiency conducting thermal path from the electronics to the equipment case. The device is particularly efficacious in circular cased electronics.

Sewell, Mark W.

1992-05-01

366

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

367

Molecular heat pump.  

PubMed

We propose a molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation wave forms, thus making it possible to optimize the device performance. PMID:16605400

Segal, Dvira; Nitzan, Abraham

2006-02-01

368

Stirling engine heating system  

SciTech Connect

A hot gas engine is described wherein a working gas flows back and forth in a closed path between a relatively cooler compression cylinder side of the engine and a relatively hotter expansion cylinder side of the engine and the path contains means including a heat source and a heat sink acting upon the gas in cooperation with the compression and expansion cylinders to cause the gas to execute a thermodynamic cycle wherein useful mechanical output power is developed by the engine, the improvement in the heat source which comprises a plurality of individual tubes each forming a portion of the closed path for the working gas.

Johansson, L.N.; Houtman, W.H.; Percival, W.H.

1988-06-28

369

Heat pumps and heat pipes for applications in cold regions  

NASA Astrophysics Data System (ADS)

Advanced active carbon fibre/NH3 heat pumps with dual sources of energy (solar/gas) were developed for providing space heating, cooling and sanitary hot water for buildings. The next heat pump generation will include a combination of chemicals with an active carbon fibre to increase the NH3 absorption. Combination of heat pipes and heat pumps solves the problem of heating the ground and air in green houses using the heat of the ground, hot ground waters, solar energy and gas flames with heat storage.

Vasiliev, Leonard L.

370

Complex Compound Chemical Heat Pumps  

E-print Network

Complex-compound solid-vapor fluid pairs can be used in heat of reaction heat pumps for temperature amplifier (TA) as well as heat amplifier (HA) cycle configurations. This report describes the conceptual hardware design for complex compound...

Rockenfeller, U.; Langeliers, J.; Horn, G.

371

Measuring the Heats of Water.  

ERIC Educational Resources Information Center

Uses common equipment (tea kettle and vacuum bottles) to precisely measure the specific heat, latent heat of fusion, and latent heat of vaporization of water. Provides descriptions for all three experiments. (MVL)

Hunt, James L.; Tegart, Tracy L.

1994-01-01

372

Industrial Heat Pump Design Options  

E-print Network

%! This paper discusses ways to use heat pumps in new process and retrofit designs, including methods to overcome problems in heat exchange fouling and high lift applications. Examples of actual designs and a simple approximation of installed heat pump cost...

Gilbert, J. S.

373

Heating Oil and Propane Update  

EIA Publications

Weekly residential, wholesale, and spot prices; and production, demand, and stocks of heating fuels. (Weekly heating oil and propane prices are only collected during the heating season which extends from October through March.)

2014-01-01

374

Diffusion-absorption heat pump  

NASA Astrophysics Data System (ADS)

The diffusion-absorption heat pump offers advantages including no moving parts, noise and vibration free operation and operation without electric power. An example of such a cycle is the gas-fired domestic refrigerator. The cycle is similar to an absorption cycle but differs in that an auxiliary gas is used to equalize the pressures throughout the system and to allow a heat driven bubble pump. A modeling study of several cycle variations of diffusion-absorption heat pump technology was conducted to calculate the potential for improving cycle performance. A computer simulation model was developed for each of the cycle variations. Thermodynamic and transport property models were developed for the ammonia/water working fluid with both hydrogen and helium as the pressure equalizing gas. The modeling results are presented for helium. The major conclusions of the study are also valid for hydrogen. The inert gas charge pressure as well as the effectiveness of the auxiliary gas heat exchanger (AGHX) were found to have a significant influence on coefficient of performance (COP). Detailed modeling of the influence of the AGHX on the COP of the cycle was performed. In addition to the thermodynamic model, fluid and heat transfer models for the AGHX have been developed. The integration of cycle fluid and heat transfer models was performed in order to examine the coupling of the components.

Wang, Lie; Herold, Keith E.

1992-06-01

375

Heat pipe cooled power magnetics  

NASA Technical Reports Server (NTRS)

A high frequency, high power, low specific weight (0.57 kg/kW) transformer developed for space use was redesigned with heat pipe cooling allowing both a reduction in weight and a lower internal temperature rise. The specific weight of the heat pipe cooled transformer was reduced to 0.4 kg/kW and the highest winding temperature rise was reduced from 40 C to 20 C in spite of 10 watts additional loss. The design loss/weight tradeoff was 18 W/kg. Additionally, allowing the same 40 C winding temperature rise as in the original design, the KVA rating is increased to 4.2 KVA, demonstrating a specific weight of 0.28 kg/kW with the internal loss increased by 50W. This space environment tested heat pipe cooled design performed as well electrically as the original conventional design, thus demonstrating the advantages of heat pipes integrated into a high power, high voltage magnetic. Another heat pipe cooled magnetic, a 3.7 kW, 20A input filter inductor was designed, developed, built, tested, and described. The heat pipe cooled magnetics are designed to be Earth operated in any orientation.

Chester, M. S.

1979-01-01

376

Thermal Hydraulic Characteristics of the Integral Type Reactor: SMART-P for Variation in Heat Removal Capability  

SciTech Connect

The SMART is an integral type reactor with new innovative design features aimed at achieving a highly enhanced safety and improved economics. This paper focuses on the thermal hydraulic experimental program for the development of SMART. Thermal hydraulic responses for the transient operations of the SMART-P are experimentally investigated by using an integral effect test facility. The test facility (VISTA) has been constructed to simulate the SMART-P, which is a pilot plant of the SMART. The VISTA facility is a full height and 1/96 volume scaled test facility with respect to the SMART-P with a power of 65 MWt. In the present study, the VISTA facility was subjected to various transient conditions in order to understand the thermal-hydraulic responses following transients and finally to verify the system design of the SMART-P. Several experiments, including a heatup, a main coolant pump (MCP) speed change, and a power change, have been performed to investigate the heat transfer characteristics and the natural circulation performance of the primary system and the Passive Residual Heat Removal System (PRHRS) of the SMART-P by using the VISTA facility. Performance tests of a passive residual heat removal system (PRHRS) have also been carried out for its design optimization. Besides, several design basis accidents, such as an increase or a decrease of the feedwater flow, a loss of coolant flow, a control rod withdrawal, and a limited case of a loss of coolant accident (LOCA) on the line to the gas cylinder are under investigation in order to understand the thermal-hydraulic responses and finally to verify the system design of the SMART-P. Especially, the details of the experimental results for a loss of feedwater accident and a power increase accident due to a control rod withdrawal are explored in the present study. (authors)

Choi, K.Y.; Cho, S.; Yi, S.J.; Park, H.S.; Choi, N.H.; Chung, M.K. [Korea Atomic Energy Research Institute, P.O. Box 7, Daedok Science Town, Daejun 302-353 (Korea, Republic of)

2006-07-01

377

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

378

HEAT TREATED WOOD  

E-print Network

Heat treated wood is a product which is obtained by intensive treatment of a wood at high temperatures (160-260 ºC). Thus, treated wood permanently changes its properties. Changes occur mainly in hemicelluloses degradation. As a consequence, the reduction of equilibrium moisture content, saturation point, shrinkage and swelling is about 50%, which leads to have more stable wood in use. Thermally treated wood shows increase in natural durability and insulating properties and reduction in water permeability. The growth of wood hardness is about 5%. Negative effects of heat treatment may include reduction of some mechanical properties (i.e. bending and tightening). The reduction of the mechanical properties is about 10-30%. Heat-treated wood is an ecologically clean material in the production and use. The most common use is for external cohesion less structure, cladding, windows, doors, flooring, saunas, swimming pools and the like. Key words: heat treated wood, properties, technology, application.

Nikola Vukas; Izet Horman; Seid Hajdarevi?

379

Structures for Reentry Heating  

NASA Technical Reports Server (NTRS)

The basic structural approaches for dealing with reentry heating of manned vehicles are summarized. The weight and development status of both radiative and ablative shields are given and the application of these shields to various vehicles is indicated.

Anderson, Roger A.; Swann, Robert T.

1960-01-01

380

Greywater heat exchanger  

SciTech Connect

A kilowatt meter and water meter were installed to monitor pregreywater usage. The design considerations, the heat exchanger construction and installation, and the monitoring of usage levels are described.

Holmberg, D.

1983-11-21

381

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

382

Heat Island Effect  

MedlinePLUS

... is part of a community's energy, air quality, water, or sustainability effort. Activities to reduce heat islands range from voluntary initiatives, such as cool pavement demonstration projects, to policy actions, such as requiring cool roofs via building ...

383

Floor heating of greenhouses  

SciTech Connect

The flooded floor system developed for solar heating of greenhouses has provided a convenient system for warming the soil for many greenhouse crops. An alternative system utilizing plastic pipes on 0.3-m spacing covered with 7 cm of porous concrete has been developed and is being utilized commercially. This system transfers heat to the greenhouse aerial environment at about two-thirds the rate of the flooded floor system. When potted plants are set on the floor, there is a significant contribution to the greenhouse heat requirement. Warm water can be provided by fossil-fuel-fired boilers, solar collectors or waste heat sources. Research results on varies pipe spacings are presented and the performance of commercial installations is discussed.

Roberts, W.J.; Mears, D.R.; James, M.F.

1981-01-01

384

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

385

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

386

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

387

Climate Wisconsin: Extreme Heat  

NSDL National Science Digital Library

Learn how extreme heat—which is projected to occur more frequently in our changing climate—disproportionately affects the urban elderly and the poor in this multimedia video produced by the Wisconsin Educational Communications Board.

Ecb, Wisconsin

2010-11-30

388

Microchannel heat exchanger optimization  

Microsoft Academic Search

A complete two-dimensional flow\\/thermal model of the micro-channel cooler is developed. Optimization of the design parameters with this model is demonstrated for the case of a 1 kW\\/cm2 heat flux with the top surface at 25°C. For this case, pure water could be used as the coolant, or 92% water\\/8% methanol (-5°C freezing point) if the heat is to be

G. M. Harpole; J. E. Eninger

1991-01-01

389

Heat storage technology update  

Microsoft Academic Search

One way to reduce vehicle cold-start emissions of unburned fuel is to reduce catalyst light-off time. The U.S. Environmental Protection Agency (EPA) has evaluated several electrically heated catalyst (EHC) technologies with favorable results at ambient temperatures of 24C and [minus]7C. The resistive heating elements reduce the time during which the catalyst remains ineffective because of insufficient warming by the cold

K. H. Hellman; G. K. Piotrowski; R. M. Schaefer

1993-01-01

390

Hurricanes as Heat Engines  

NSDL National Science Digital Library

As water vapor evaporates from the warm ocean surface, it is forced upward in the convective clouds that surround the eyewall and rainband regions of a storm. As the water vapor cools and condenses from a gas back to a liquid state, it releases latent heat. The release of latent heat warms the surrounding air, making it lighter and thus promoting more vigorous cloud development.

Byrne, Susan; Adler, Robert

2000-05-03

391

Heat Pipe Systems  

NASA Technical Reports Server (NTRS)

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

392

Latent heat diode wall  

NASA Astrophysics Data System (ADS)

A composite wall with separate collector side and storage volume operating as a thermal diode is proposed. The storage uses a latent heat material called chliarolithe. Laboratory experiments performed on the storage side show that it is possible to define satisfactory conditions both for the collector side and for the heat restitution: relatively low temperature in collector, little external losses, storage equivalent to 75 cm of concrete in the form of 5 cm of chliarolithe, excellent temperature control on the internal side.

Bourdeau, L.; Jaffrin, A.

393

Industrial Waste Heat Recovery  

E-print Network

INDUSTRIAL WASTE HEAT RECOVREY M. E. Ward and N. G. Solomon E. S. Tabb Solar Turbines International and Gas Research Institute San Diego, California Chicago, Illinois ABSTRACT i I One hundred fifty reports were reviewed along with interviews...INDUSTRIAL WASTE HEAT RECOVREY M. E. Ward and N. G. Solomon E. S. Tabb Solar Turbines International and Gas Research Institute San Diego, California Chicago, Illinois ABSTRACT i I One hundred fifty reports were reviewed along with interviews...

Ward, M. E.; Solomon, N. G.; Tabb, E. S.

1980-01-01

394

Mechanical Compression Heat Pumps  

E-print Network

plants: - Breweries - Citrus fruit packing and canning plants - Dairy Processing, and all plants where simultaneous cooling and heating is done (e.g. pasteurization of beer and milk). These are just a handful of plants which can profit out... plants: - Breweries - Citrus fruit packing and canning plants - Dairy Processing, and all plants where simultaneous cooling and heating is done (e.g. pasteurization of beer and milk). These are just a handful of plants which can profit out...

Apaloo, T. L.; Kawamura, K.; Matsuda, J.

395

Nanofabrication using heated probe tips  

NASA Astrophysics Data System (ADS)

We present progress towards scalable, high precision nanofabrication in a variety of materials using heated Atomic Force Microscope (AFM) probes. Temperature control of a heated AFM tip allows nanometer scale thermochemical patterning, deposition of thermoplastic polymers, and surface melting. The challenges that must be overcome to scale such a technology to industrial-scale manufacturing include tip wear, thermal and mechanical control of the cantilever, chemical reaction control at the tip-surface interface, and fabrication throughput. To mitigate tip wear, we have integrated nanocrystalline diamond films onto our heated AFM probe tip. Such diamond tips are extremely resistant to wear and fouling at a self-heating temperature of 400 C and load force of 200 nN over long distances. To improve cantilever temperature control, a closed loop feedback control was designed to allow for 0.2 C precision temperature control during nanolithography. Electrohydrodynamic jetting controls the deposition of polyethylene onto a heated probe tip. Finally, to address throughput, we have fabricated cantilever arrays having independent temperature control and integrated them into a commercial AFM system. We show these advances by patterning thousands of nanostructures of polyethylene and poly(3-dodecylthiophene), with cumulative length more than 2 mm and patterning accuracy better than 50 nm.

Felts, Jonathan R.; Fletcher, Patrick C.; Somnath, Suhas; Pikul, James; Dai, Zhenting; Lee, Woo Kyung; Sheehan, Paul E.; King, William P.

2011-06-01

396

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

397

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

398

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, John C. (Los Alamos, NM); Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)

1984-01-01

399

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. 11 figs.

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

1984-12-25

400

Heat Transport in Graphene  

NASA Astrophysics Data System (ADS)

We fabricated suspended graphene devices and measured their thermal conductivity, ?, as a function of both temperature, T, and charge carrier density, n. Heat transport is a powerful tool to obtain information about both the phononic and electronic properties of graphene. Recent heat transport experiments in graphene have shown a high ?, but a detailed mapping of graphene's heat conductivity versus T and n is not yet available. The measurement technique we developed is a two-point method which uses graphene as its own heat source (Joule heating) and thermometer (resistivity). We report ? at temperatures ranging from 6 to 350 Kelvin, and at charge carrier densities close to the Dirac point up to about 1.5 x10^11/cm^2, in graphene crystals whose length varies from 250 nm up to one micron. We observed that the thermal conductivity increases by over two orders of magnitude over the temperature range, and that it also increases with the crystal's length. ? can be tuned by an order of magnitude with gate voltage, opening the possibility of creating room temperature heat transistors.

Yigen, Serap; Tayari, Vahid; Island, Joshua O.; Porter, James; Champagne, A. R.

2012-02-01

401

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 packer-type seals are provided along the probe above and below the heater pads.

Dunn, James C. (Albuquerque, NM); Hardee, Harry C. (Albuquerque, NM); Striker, Richard P. (Albuquerque, NM)

1985-01-01

402

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

403

Mapping a Wind-Modified Urban Heat Island in Tucson, Arizona (with Comments on Integrating Research and Undergraduate Learning).  

NASA Astrophysics Data System (ADS)

Tucson, Arizona, is an example of the many cities in the southwestern United States experiencing rapid growth and urban sprawl over the last several decades. The accompanying extensive modification of land use and land cover leads to many environmental impacts, including urban heat islands. The primary aim of this paper is to expand knowledge of the phenomenon for Tucson, by quantifying the amount of urban warming, and by mapping temperature patterns over the city and examining related aspects of the local-scale atmospheric circulation. The secondary aim is to document how an applied empirical research project was integrated into an introductory undergraduate climatology class via active learning. The paper begins and concludes with general and practical comments on combining the research and educational aspects of the project. An analysis of 30-yr temporal trends in urban and nonurban minimum temperatures across the region shows the rate of urban warming to be about three-quarters of the general regional warming. Tucson's urban heat island is ~3°C over the last century, with >2°C of this warming in the last 30 years. The annual average urban warming trend over the last three decades is 0.071°C yr-1 with the strongest effect in March and the weakest effect in November. There is evidence that the latter is caused by strong, near-surface winds under stable conditions. A case study is presented comprising field measurements and map analysis of urban temperatures and supporting variables for 13 February 1999. Measurements include comprehensive mapping using vehicle-mounted thermistors and numerous local meteorological observations from around the city. Wind speeds during the field measurements were somewhat stronger than is typical of heat island studies, up to 12 m s-1. Nonetheless, because of terrain-induced flows and land surface heterogeneity, complex temperature patterns were observed. Several transient katabatic flows off surrounding mountain ranges were detected, leading to localized cold pockets. Locally warm areas in other parts of the city are associated with terrain sheltering or local land surface heating. The central city showed a possible urban heating pattern with temperatures ~2°C higher than upwind rural air.

Comrie, Andrew C.

2000-10-01

404

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

405

NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger  

SciTech Connect

One key long-standing issue that must be overcome to fully realize the successful growth of nuclear power is to determine other benefits of nuclear energy apart from meeting the electricity demands. The Next Generation Nuclear Plant (NGNP) will most likely be producing electricity and heat for the production of hydrogen and/or oil retrieval from oil sands and oil shale to help in our national pursuit of energy independence. For nuclear process heat to be utilized, intermediate heat exchange is required to transfer heat from the NGNP to the hydrogen plant or oil recovery field in the most efficient way possible. Development of nuclear reactor - process heat technology has intensified the interest in liquid metals as heat transfer media because of their ideal transport properties. Liquid metal heat exchangers are not new in practical applications. An important rational for considering liquid metals is the potential convective heat transfer is among the highest known. Thus explains the interest in liquid metals as coolant for intermediate heat exchange from NGNP. For process heat it is desired that, intermediate heat exchangers (IHX) transfer heat from the NGNP in the most efficient way possible. The production of electric power at higher efficiency via the Brayton Cycle, and hydrogen production, requires both heat at higher temperatures and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. Compact heat exchangers maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. High temperature IHX design requirements are governed in part by the allowable temperature drop between the outlet and inlet of the NGNP. In order to improve the characteristics of heat transfer, liquid metal phase change heat exchangers may be more effective and efficient. This paper explores the overall heat transfer characteristics and pressure drop of the phase change heat exchanger with Na as the heat exchanger coolant. In order to design a very efficient and effective heat exchanger one must optimize the design such that we have a high heat transfer and a lower pressure drop, but there is always a trade-off between them. Based on NGNP operational parameters, a heat exchanger analysis with the sodium phase change will be presented to show that the heat exchanger has the potential for highly effective heat transfer, within a small volume at reasonable cost.

Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

2008-09-01

406

Industrial heat pipe energy recovery package unit  

SciTech Connect

This invention relates in general to an industrial heat exchanger package unit for transferring heat energy between cool intake air flowing into an industrial process, and hot exhaust air flowing out of an industrial process. Each package units specifically include integral finned heat pipe heat exchangers, face and bypass damper assemblies, tilted base frames, bypass ducts, supply inlet filter assemblies, and supply inlet louver assemblies which are arranged in such a manner as to provide a percentage of total volume control over the amount of supply or exhaust air introduced into the heat exchange chambers.

Bagno, A.C.

1981-11-10

407

Cascade heat recovery with coproduct gas production  

DOEpatents

A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange. 4 figs.

Brown, W.R.; Cassano, A.A.; Dunbobbin, B.R.; Rao, P.; Erickson, D.C.

1986-10-14

408

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

409

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

410

Optimum control of heat exchangers with internal heat generation  

Microsoft Academic Search

This paper investigates the optimum control of a heat exchanger having internal heat sources from a reference steady state to a desired value. Both the wall and coolant are treated as distributed-parameter systems. Under certain constraints inherent in the operating conditions and physical limitations of the heat exchanger, the control function of the system, i.e. the heat generation rate which

H. S. Huang; W. J. Yang

1971-01-01

411

High temperature latent heat thermal energy storage using heat pipes  

Microsoft Academic Search

A thermal network model is developed and used to analyze heat transfer in a high temperature latent heat thermal energy storage unit for solar thermal electricity generation. Specifically, the benefits of inserting multiple heat pipes between a heat transfer fluid and a phase change material (PCM) are of interest. Two storage configurations are considered; one with PCM surrounding a tube

H. Shabgard; T. L. Bergman; N. Sharifi; A. Faghri

2010-01-01

412

Solar greenhouse heating using an underground heat exchange system  

Microsoft Academic Search

The air temperature in a greenhouse on a sunny day often exceeds the optimum temperature level for the growth of crops. Therefore, there are frequent occasions when it becomes necessary to discharge the excess heat. This has given rise to the development by some investigators of an underground heat exchange system for heating greenhouses which utilizes this excess heat. The

T. Masao; D. Kiyoshi; O. Toshiaki; O. Yoshihiro

1982-01-01

413

Method of heating a building structure with solar heat  

Microsoft Academic Search

A method of heating a building structure comprising the steps of: absorbing solar heat on a collector surface wherein said collector surface is insulated from the ambient environment, passing air across the collector surface in a heat transfer process whereby the heat absorbed by the collector surface is transferred to the air, passing the hot air leaving the collector surface

J. H. Keyes; C. I. Strickland; R. G. Strickland

1974-01-01

414

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

415

Solar air heating system for combined DHW and space heating  

E-print Network

Solar air heating system for combined DHW and space heating solar air collector PV-panel fannon-return valve DHW tank mantle cold waterhot water roof Solar Energy Centre Denmark Danish Technological Institute SEC-R-29 #12;Solar air heating system for combined DHW and space heating Søren �stergaard Jensen

416

Quantitative Assessment of the Integrated Response in Global Heat and Moisture Budgets to Changing Solar Irradiance  

NASA Technical Reports Server (NTRS)

Earlier, we found time sequences of basin- and global-average upper ocean temperature (that is, diabatic heat storage above the main pycnocline) for 40 years from 1955-1994 and of sea surface temperature for 95 years from 1900-1994 associated with changes in the Sun's radiative forcing on decadal and interdecadal timescales, lagging by 10 deg.- 30 deg. of phase and confined to the upper 60-120 m. Yet, the observed changes in upper ocean temperature (approx. 0.1 K) were approximately twice those expected from the Stefan-Boltzmann black-body radiation law for the Earth's surface, with phase lags (0 deg. to 30 deg. of phase) much shorter than the 90 deg. phase shift expected as well. Moreover, White et al. (1997, 1998) found the Earth's global decadal mode in covarying SST and SLP anomalies phase locked to the decadal signal in the Sun's irradiance. Yet, Allan (2000) found this decadal signal also characterized by patterns similar to those observed on biennial and interannual time scales; that is, the Troposphere Biennial Oscillation (TBO) and the El Nino and the Southern Oscillation (ENSO). This suggested that small changes in the Sun's total irradiance could excite this global decadal mode in the Earth's ocean-atmosphere-terrestrial system similar to those excited internally on biennial and interannual period scales. This is a significant finding, proving that energy budget models (that is, models based on globally-averaged radiation balances) yield unrealistic responses. Thus, the true response must include positive and negative feedbacks in the Earth's ocean-atmosphere-terrestrial system as its internal mode (that is, the natural mode of the system) respond in damped resonance to quasi-periodic decadal changes in the Sun's irradiance. Moreover, these responses are not much different from those occurring internally on biennial and interannual period scales.

White, Warren B.; Cayan, Daniel R.; Dettinger, Michael; Sharber, James (Technical Monitor)

2001-01-01

417

Thermodynamic analysis of chemical heat storage system for heat pump  

NASA Astrophysics Data System (ADS)

In order to establish a performance index of chemical heat storage, a method of assessment was proposed wherein the action principles were adjusted as well as the examples of the application. In a chemical heat storage system wherein the exhaust heat at heat storage operation and the driving heat source at the exothermic operation and the compressor power are utilized, the driving force cannot be neglected; heat must be assessed not only by quantity but also by the temperature level (in other words by both heat and power). By examining the flow of enthalpy and the exergy using a method of exergy analysis, the characteristics of chemical heat storage was grasped, and it was found that exergy efficiency could be defined in various ways including the above-mentioned exhaust heat and the driving heat source. In other words, the definition should be made according to each case of the application.

Saikawa, Michiyuki; Iwatsubo, Tetsushiro; Hamamatsu, Teruhide

1987-09-01

418

CFD modeling of buoyancy driven cavities with internal heat source -Application to heated rooms  

E-print Network

1 CFD modeling of buoyancy driven cavities with internal heat source - Application to heated rooms. In addition, we present here a simplified approach in order to integrate a pure buoyancy source within our. Keywords: CFD - Computational Fluid Dynamics modeling; buoyancy driven cavity; heat source; thermal plume

419

PERFORMANCE EVALUATION OF AN AIR-TO-AIR HEAT PUMP COUPLED WITH TEMPERATE AIR-SOURCES INTEGRATED INTO A DWELLING  

E-print Network

and implemented in the thermal simulation tool COMFIE, in order to compare the seasonal performance of a variable are studied and applied on a case study: a French typical residential house. The influence of the climatic envelope can contribute to increase the heat pump's heat-source temperature, as for instance sunspaces

Paris-Sud XI, Université de

420

Heat-Of-Reaction Chemical Heat Pumps--Possible Configurations  

E-print Network

, forming a new solid. This reaction is exothermic and conducted at required process temperature, with heat being rejected to 'the load. Regeneration is accomplished by operating at reduced system pressure. The reaction with A and C is reversed, with C...-vapor reversible reaction heat pump and heat engine Heat pumps involving reactions of metal hydrides and hydrogen are of this class and have been the subject of considerable investigation for cryogenic refrigeration (15) and heat pumping. Argonne National...

Kirol, L. D.

421

Machinability of Austempered Ductile Iron (ADI) Produced by Integrated Green Technology of Continuous Casting-Heat Treatment Processes  

SciTech Connect

This study presents the novel processing technique known as continuous casting-heat treatment processes to produce Austempered Ductile Iron (ADI) which is a new class of ductile iron. ADI is characterized by improved mechanical properties but has low machinability as compared to other cast irons and steel of similar strength. The novel technique is developed by the integration of casting (in die casting) and heat treatment processes in foundry to save cost energy and time. Specimens just after casting were austenitized at 930 deg. C for 90 min and then austempered in fluidized bed at 380 deg. C for 90 and 120 min. Hence, the effect of austempering time on the morphology of retained austenite and mechanical properties of the material were examined and compared with conventionally produced ADI. Drilling tests were then carried out to evaluate the machinability of ADI in terms of cutting forces, chip micro-hardness, chip morphology and surface roughness. The mechanical properties of ADI austempered for 120 min have found to be better as compare to the ADI austempered for 90 min.

Meena, A.; El Mansori, M.; Ghidossi, P. [Arts et Metiers ParisTech, LMPF-EA 4106, Rue Saint Dominique, BP 508, 51006, Chalons-en-Champagne, Cedex (France)

2011-01-17

422

Integrated assessment of supply and efficiency resources for the district heating system, City of Handlova, Republic of Slovakia  

SciTech Connect

This city needs to replace its old district heating system which is unreliable and expensive to maintain. Current plant is owned by a state-run utility; the plant is scheduled for privatization, and the city is examining options for its upgrade. Analysis and preparation for this activity is documented in demand-side and supply-side technical and economic analyses and in this integrated demand/supply report. Preliminary projections indicate the cost of heating from a cost per unit of energy basis and from the perspective of an apartment dweller in Handlova on a total cost per year basis. The centralized coal cogeneration option is the least expensive on a levelized energy cost both with and without energy efficiency. Centralized coal/gas dual-fuel cogeneration is a close second, and the decentralized gas natural gas boilers is significantly more expensive. When the effect of building efficiency measures is evaluated, efficiency always increases the cost on a levelized energy cost basis, but on a levelized cost per flat basis, both centralized systems with buildings efficiency are less expensive than without.

NONE

1996-06-01

423

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

424

Waste heat energy recovery system  

Microsoft Academic Search

A heat exchange element is inserted directly into a water heater storage tank of a new or existing water heating system. The heat exchange element is provided with standard pipe thread connections and adapted to be installed in standard threaded openings in conventional tanks. The heat exchange element is an elongate outer tube inserted vertically through the top of the

1981-01-01

425

Heat simulation via Scilab programming  

NASA Astrophysics Data System (ADS)

This paper discussed the used of an open source sofware called Scilab to develop a heat simulator. In this paper, heat equation was used to simulate heat behavior in an object. The simulator was developed using finite difference method. Numerical experiment output show that Scilab can produce a good heat behavior simulation with marvellous visual output with only developing simple computer code.

Hasan, Mohammad Khatim; Sulaiman, Jumat; Karim, Samsul Arifin Abdul

2014-07-01

426

Policies supporting Heat Pump Technologies  

E-print Network

heating equipment $1,500 -- air-source heat pump ENERGY STAR central system verified with an AHRI number on a different floor, ENERGY STAR or LiveSmart qualified inverter-based system $1,000 -- air-source heat pump or LiveSmart qualified inverter-based system $1,000 -- air-source heat pump ENERGY STAR single package

Oak Ridge National Laboratory

427

Heat transfer within combusting droplets  

Microsoft Academic Search

The improvement of the basic understanding of heat transfer in sprays is a key point in many engineering applications. In this paper, the temperature field within combusting ethanol droplets in linear stream is investigated by the two-color laser induced fluorescence technique. Additionally, a heat transfer model within the droplet is developed, taking into account both heat conduction and heat advection

G. Castanet; F. Lemoine

2007-01-01

428

Heating system with vapour compressor heat pump and vertical U-tube ground heat exchanger  

NASA Astrophysics Data System (ADS)

In the paper a heating system with a vapour compressor heat pump and vertical U-tube ground heat exchanger for small residential house is considered. A mathematical model of the system: heated object - vapour compressor heat pump - ground heat exchanger is presented shortly. The system investigated is equipped, apart from the heat pump, with the additional conventional source of heat. The processes taking place in the analyzed system are of unsteady character. The model consists of three elements; the first containing the calculation model of the space to be heated, the second - the vertical U-tube ground heat exchanger with the adjoining area of the ground. The equations for the elements of vapour compressor heat pump form the third element of the general model. The period of one heating season is taken into consideration. The results of calculations for two variants of the ground heat exchanger are presented and compared. These results concern variable in time parameters at particular points of the system and energy consumption during the heating season. This paper presents the mutual influence of the ground heat exchanger subsystem, elements of vapour compressor heat pump and heated space.

Hanuszkiewicz-Drapa?a, Ma?gorzata; Sk?adzie?, Jan

2010-10-01

429

High Efficiency Integrated Space Conditioning, Water Heating and Air Distribution System for HUD-Code Manufactured Housing  

SciTech Connect

Recognizing the need for new space conditioning and water heating systems for manufactured housing, DeLima Associates assembled a team to develop a space conditioning system that would enhance comfort conditions while also reducing energy usage at the systems level. The product, Comboflair® was defined as a result of a needs analysis of project sponsors and industry stakeholders. An integrated system would be developed that would combine a packaged airconditioning system with a small-duct, high-velocity air distribution system. In its basic configuration, the source for space heating would be a gas water heater. The complete system would be installed at the manufactured home factory and would require no site installation work at the homesite as is now required with conventional split-system air conditioners. Several prototypes were fabricated and tested before a field test unit was completed in October 2005. The Comboflair® system, complete with ductwork, was installed in a 1,984 square feet, double-wide manufactured home built by Palm Harbor Homes in Austin, TX. After the home was transported and installed at a Palm Harbor dealer lot in Austin, TX, a data acquisition system was installed for remote data collection. Over 60 parameters were continuously monitored and measurements were transmitted to a remote site every 15 minutes for performance analysis. The Comboflair® system was field tested from February 2006 until April 2007. The cooling system performed in accordance with the design specifications. The heating system initially could not provide the needed capacity at peak heating conditions until the water heater was replaced with a higher capacity standard water heater. All system comfort goals were then met. As a result of field testing, we have identified improvements to be made to specific components for incorporation into production models. The Comboflair® system will be manufactured by Unico, Inc. at their new production facility in St. Louis, MO. The product will be initially launched in the hot-humid climates of the southern U.S.

Henry DeLima; Joe Akin; Joseph Pietsch

2008-09-14

430

Heat pipe cooling for scramjet engines  

NASA Technical Reports Server (NTRS)

Liquid metal heat pipe cooling systems have been investigated for the combustor liner and engine inlet leading edges of scramjet engines for a missile application. The combustor liner is cooled by a lithium-TZM molybdenum annular heat pipe, which incorporates a separate lithium reservoir. Heat is initially absorbed by the sensible thermal capacity of the heat pipe and liner, and subsequently by the vaporization and discharge of lithium to the atmosphere. The combustor liner temperature is maintained at 3400 F or less during steady-state cruise. The engine inlet leading edge is fabricated as a sodium-superalloy heat pipe. Cooling is accomplished by radiation of heat from the aft surface of the leading edge to the atmosphere. The leading edge temperature is limited to 1700 F or less. It is concluded that heat pipe cooling is a viable method for limiting scramjet combustor liner and engine inlet temperatures to levels at which structural integrity is greatly enhanced.

Silverstein, Calvin C.

1986-01-01

431

Gravitational heating, clumps, overheating  

E-print Network

There is no shortage of energy around to solve the overcooling problem of cooling flow clusters. AGNs, as well as gravitational energy are both energetic enough to balance the cooling of cores of clusters. The challenge is to couple this energy to the baryons efficiently enough, and to distribute the energy in a manner that will not contradict observational constraints of metalicity and entropy profiles. Here we propose that if a small fraction of the baryons that are accreted to the cluster halo are in the form of cold clumps, they would interact with the hot gas component via hydrodynamic drag. We show that such clumps carry enough energy, penetrate to the center, and heat the core significantly. We then study the dynamic response of the cluster to this kind of heating using a 1D hydrodynamic simulation with sub-grid clump heating, and produce reasonable entropy profile in a dynamic self-consistent way.

Birnboim, Yuval

2009-01-01

432

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

433

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

434

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

435

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

436

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

437

Rotary Joint for Heat Transfer  

NASA Technical Reports Server (NTRS)

Rotary joint exchanges heat between two heat pipes - one rotating and one stationary. Joint accommodates varying heat loads with little temperature drop across interface. According to concept, heat pipe enters center of disklike stationary section of joint. There, wicks in central artery of heat pipe separate into multiple strands that lead to concentric channels on rotaryinterface side of stationary disk. Thin layer of liquid sodium/potassium alloy carries heat from one member of rotary joint to other. Liquid conducts heat efficiently while permitting relative motion between members. Polypropylene rings contain liquid without interfering with rotation.

Shauback, R.

1986-01-01

438

Multileg Heat-Pipe Evaporator  

NASA Technical Reports Server (NTRS)

Parallel pipes provide high heat flow from small heat exchanger. Six parallel heat pipes extract heat from overlying heat exchanger, forming evaporator. Vapor channel in pipe contains wick that extends into screen tube in liquid channel. Rods in each channel hold wick and screen tube in place. Evaporator compact rather than extended and more compatible with existing heat-exchanger geometries. Prototype six-pipe evaporator only 0.3 m wide and 0.71 m long. With ammonia as working fluid, transports heat to finned condenser at rate of 1,200 W.

Alario, J. P.; Haslett, R. A.

1986-01-01

439

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

440

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)

1996-12-31

441

Ceramic heat recuperators for industrial heat recovery  

NASA Astrophysics Data System (ADS)

A cordierite (magnesium aluminum silicate) recuperator was designed for relatively small furnaces with firing rates of 0.3 MM to 0.6 MM Btu/h and with exhaust gas temperatures of 1500 F to 2600 F. Five demonstration programs were performed to determine the heat transfer performance of the device, establish the energy savings by recovery, demonstrate the durability of the ceramic core, determine the operating requirements of the burners and controls with recuperation, and establish the overall system costs and payback period. The recuperator is described and results of tests and measurements, system economics, and cost performance analyses are presented. The methodology is developed and techniques for impact analysis are described. Industrial applications are implied and a process flow diagram for smelting and refining primary copper is shown.

Cleveland, J. J.; Gonzalez, J. M.; Kohnken, K. H.; Rebello, W. J.

1980-08-01

442

Gaseous Nitrogen Heat Exchanger  

SciTech Connect

A heat exchanger is necessary to warm the gaseous nitrogen from the nitrogen dewar from 77 K to ambient temperature for use in the D-Zero Building. The original proposal would use an ambient air vaporizer, but further investigation led to the consideration and evaluation of other possibilities and a different final system. The vaporizer must be able to handle a flow rate of 1200 scfh at 30 psig on a continuous basis subject to local weather conditions. Upon consulting with a representative from Thermax Incorporated, So. Dartmouth, Massachusetts, four different heat exchanging systems were proposed. Their advantages and disadvantages are stated.

Kurita, C.H.; /Fermilab

1988-08-19

443

Heat-recovery economics  

SciTech Connect

Payback period is discussed as a criterion for making an investment decision. To demonstrate the method of determining payback periods and the present worth cost of a heat-reclaim system, an actual case is examined where a decision had to be made whether or not a heat-reclaim system should be installed in a student dining hall of a college in New England. The relatively simple case illustrates the use of several key factors in producing a meaningful life-cycle costing analysis.

Yanuck, R.R.

1981-01-01

444

[Pathophysiology of heat illness].  

PubMed

Human core temperature is strictly controlled by mechanism of radiation, conduction, convection, and evaporation from skin surface. Serial hot and humid climate induces dehydration which interferes heat pump-out from the body. Heart dysfunction is the third factor to rise body temperature. Hyperthermia and hypo-perfusion caused by dehydration and heart failure deteriorate specific organ functions, i.e. central nervous system, liver and renal functions and coagulation system. Disseminated intravascular coagulopathy is one of the standard indicators of severity and mortality of heat stroke. PMID:22690597

Aruga, Tohru; Miyake, Yasufumi

2012-06-01

445

Air heating system  

DOEpatents

A self-starting, fuel-fired, air heating system including a vapor generator, a turbine, and a condenser connected in a closed circuit such that the vapor output from the vapor generator is conducted to the turbine and then to the condenser where it is condensed for return to the vapor generator. The turbine drives an air blower which passes air over the condenser for cooling the condenser. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with the provision of heat exchanger and circuitry for cooling the condensed fluid output from the pump prior to its return to the vapor generator.

Primeau, John J. (19800 Seminole Rd., Euclid, OH 44117)

1983-03-01

446

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

447

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

448

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

449

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

450

Engine heating device. Final report  

Microsoft Academic Search

The engine heating device development project was supported by DOE grant No. DE-FG01-82CE15141. The engine heating device is a device which recovers waste engine exhaust heat and stores it for later use in rewarming the cold engine prior to starting. Heat is stored in the phase change and sensible heat capacity of a storage material. This device finds application in

1986-01-01

451

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

452

Chemical heat pump program: An overview  

NASA Astrophysics Data System (ADS)

Chemical heat pumps comprise reversible reactions which can be driven by low grade heat. Thermal energy is absorbed in one direction and liberated in the reverse direction; thus, serving as a basis for system designs applicable to space conditioning or process heat management and offering the capability for high density energy storage as an integral part of the system. The program background, rationale, technology, and research and development needs are described.

Mezzina, A.

453

Analysis of Influencing Factors of Heat Transfer Performance of Heat Pipe Heat Exchanger  

Microsoft Academic Search

Heat transfer performance of heat pipe heat exchanger affected by many factors, such as the opening temperature of the heat pipe, the rate of fluid-filled, the physical nature of liquid refrigerant, the work temperature of tube, angle, tube spacing, tube length, hot and cold fluid flow and wind speed. The above-mentioned parameters can not be measured because of Test conditions,

Zhang Jie; Ren Yan; Zhang Lihong; Liang Huimin

2009-01-01

454

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

455

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

456

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

457

Solar corona heating  

Microsoft Academic Search

Despite of the large number of models and mechanisms proposed in the literature, the problem of the heating of the solar corona is still unsolved and represents one of the challenge of solar physics. In this context, a basic question to be addressed by any viable theoretical model concerns understanding the mechanism capable of transferring ``efficiently'' the energy from the

Francesco Califano

2000-01-01

458

Urban Heat Island  

NSDL National Science Digital Library

While this MPEG could have been better designed to show how and why urban areas absorb more heat than surrounding vegetated areas, there is value in seeing enhanced convection over the city, cloud formation favored by increased condensation nuclei, and increased showers downwind of the city.

Gsfc, Nasa; Nasa

459

Solitons and ionospheric heating  

NASA Technical Reports Server (NTRS)

It is noted that for parameters characterizing the Platteville ionospheric heating facility, the Langmuir wave evolution at the exact reflection point of the heater wave involves an oscillating two-stream instability followed by a collisionally damped three-dimensional soliton collapse. The result gives an alternative explanation for certain experimental observations.

Weatherall, J. C.; Goldman, M. V.; Sheerin, J. P.; Nicholson, D. R.; Payne, G. L.; Hansen, P. J.

1982-01-01

460

Sudurnes Regional Heating Corp.  

SciTech Connect

The Svartsengi geothermal area is close to the town of Grindavik on the Rekjanes peninsula and is part of an active fissure swarm, lined with crater-rows and open fissures and faults. The high-temperature area has an area of 2 sq. km and shows only limited signs of geothermal activity at the surface. The reservoir, however, contains lots of energy and at least 8 wells supply the Svartsengi Power Plant with steam. The steam is not useable for domestic heating purposes so that heat exchangers are used to heat cold groundwater with the steam. Some steam is also used for producing 16.4 MW{sub e} of electrical power. The article shows the distribution system piping hot water to nine towns and the Keflavik International Airport. The effluent brine from the Svartsengi Plant is disposed of into a surface pond, called the Blue Lagoon, popular to tourists and people suffering from psoriasis and other forms of eczema seeking therapeutic effects from the silica rich brine. This combined power plant and regional district heating system (cogeneration) is an interesting and unique design for the application of geothermal energy.

Lienau, P.J. [ed.

1996-11-01

461

Wastewater heat recovery apparatus  

DOEpatents

A heat recovery system with a heat exchanger and a mixing valve. A drain trap includes a heat exchanger with an inner coiled tube, baffle plate, wastewater inlet, wastewater outlet, cold water inlet, and preheated water outlet. Wastewater enters the drain trap through the wastewater inlet, is slowed and spread by the baffle plate, and passes downward to the wastewater outlet. Cold water enters the inner tube through the cold water inlet and flows generally upward, taking on heat from the wastewater. This preheated water is fed to the mixing valve, which includes a flexible yoke to which are attached an adjustable steel rod, two stationary zinc rods, and a pivoting arm. The free end of the arm forms a pad which rests against a valve seat. The rods and pivoting arm expand or contract as the temperature of the incoming preheated water changes. The zinc rods expand more than the steel rod, flexing the yoke and rotating the pivoting arm. The pad moves towards the valve seat as the temperature of the preheated water rises, and away as the temperature falls, admitting a variable amount of hot water to maintain a nearly constant average process water temperature.

Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

1992-01-01

462

Heat and temperature  

NSDL National Science Digital Library

Knowing the difference between heat and temperature is important if one is to have a clear understanding of energy. In this section we will define both terms and reach an understanding of how they are related ideas, but not identical ideas.

Zobel, Edward A.

1997-01-01

463

Solar Energy: Heat Storage.  

ERIC Educational Resources Information Center

This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

Knapp, Henry H., III

464

Solar energy heating panel  

Microsoft Academic Search

A solar energy collecting and radiating panel for heating a fluid such as air circulating in an enclosure disposed behind the panel. The panel is in the form of a pan made of sheet metal, such as thin aluminum, darkened on its irradiated surface, the blackened or darkened surface being protected by a pane of glass. The panel has a

McMurtrie

1984-01-01

465

Heat pipe thermal switch  

NASA Technical Reports Server (NTRS)

A thermal switch for controlling the dissipation of heat between a body is described. The thermal switch is comprised of a flexible bellows defining an expansible vapor chamber for a working fluid located between an evaporation and condensation chamber. Inside the bellows is located a coiled retaining spring and four axial metal mesh wicks, two of which have their central portions located inside of the spring while the other two have their central portions located between the spring and the side wall of the bellows. The wicks are terminated and are attached to the inner surfaces of the outer end walls of evaporation and condensation chambers respectively located adjacent to the heat source and heat sink. The inner surfaces of the end walls furthermore include grooves to provide flow channels of the working fluid to and from the wick ends. The evaporation and condensation chambers are connected by turnbuckles and tension springs to provide a set point adjustment for setting the gap between an interface plate on the condensation chamber and the heat sink.

Wolf, D. A. (inventor)

1983-01-01

466

Heating Systems Specialist.  

ERIC Educational Resources Information Center

This instructional package is intended for use in training Air Force personnel enrolled in a program for apprentice heating systems specialists. Training includes instruction in fundamentals and pipefitting; basic electricity; controls, troubleshooting, and oil burners; solid and gas fuel burners and warm air distribution systems; hot water…

Air Force Training Command, Sheppard AFB, TX.

467

Glovebox heat test  

Microsoft Academic Search

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

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

2002-01-01

468

Rf heating of mirrors  

SciTech Connect

A brief overview is presented of potential uses for rf heating of plasmas in mirror devices. While some discussion relating to past experiments is given, the main emphasis is devoted to a review of potential experiments in presently existing devices, and devices under construction or planning. Some predictions are made for plasmas in mirror reactors.

Porkolab, M.

1980-04-09

469

Heat Transfer Technical Brief  

E-print Network

in nucleate and film boiling regimes to investigate the effect of MWCNT height on pool boiling performance level, and working fluid on nucleate boiling were re- ported in this study. The thermal conductivityJournal of Heat Transfer Technical Brief Pool Boiling Experiments on Multiwalled Carbon Nanotube

Banerjee, Debjyoti

470

Understanding heat transfer  

NSDL National Science Digital Library

Understanding Heat Transfer is a graduate-level professional development course designed for middle school teachers to enhance understanding and teaching of physical science. In two sessions, you will investigate physical science topics using hands-on activities and online resources including video segments, interactive activities, readings, and other multimedia materials. These resources are drawn from Teachers' Domain, WGBH's digital library service.

2010-01-01