National Library of Energy BETA

Sample records for heat exchangers finer

  1. Heat exchanger

    DOE Patents [OSTI]

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  2. HEAT EXCHANGER

    DOE Patents [OSTI]

    Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

    1962-10-23

    A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

  3. Heat exchanger

    DOE Patents [OSTI]

    Wolowodiuk, Walter

    1976-01-06

    A heat exchanger of the straight tube type in which different rates of thermal expansion between the straight tubes and the supply pipes furnishing fluid to those tubes do not result in tube failures. The supply pipes each contain a section which is of helical configuration.

  4. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L.

    1989-01-01

    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.

  5. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, P.J.

    1983-12-08

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  6. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, Phillip J.

    1986-01-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  7. Heat exchanger

    DOE Patents [OSTI]

    Brackenbury, Phillip J.

    1986-04-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  8. Segmented heat exchanger

    DOE Patents [OSTI]

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    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.

  9. Heat pipe array heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C.

    1987-08-25

    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.

  10. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16

    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.

  11. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R.

    1987-01-01

    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.

  12. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R.

    1987-05-05

    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.

  13. Direct fired heat exchanger

    DOE Patents [OSTI]

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

    1986-01-01

    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.

  14. Wound tube heat exchanger

    DOE Patents [OSTI]

    Ecker, Amir L.

    1983-01-01

    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.

  15. Active microchannel heat exchanger

    DOE Patents [OSTI]

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

    2001-01-01

    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.

  16. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc J.; Miller, Jeffrey A.; Tonon, Thomas

    2007-09-18

    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.

  17. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc J.; Miller, Jeffrey A.; Tonon, Thomas

    2011-06-28

    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.

  18. Thermoelectric heat exchange element

    DOE Patents [OSTI]

    Callas, James J.; Taher, Mahmoud A.

    2007-08-14

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

  19. A corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, S.L.

    1987-08-10

    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.

  20. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier

    2001-01-01

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

  1. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-02-28

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4kA was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summarized herein.

  2. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-03-18

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4A was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the identified tube. The leaking tube was removed and examined metallurgically to determine the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summary herein.

  3. Heat exchanger restart evaluation

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-03-18

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4A was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the identified tube. The leaking tube was removed and examined metallurgically to determine the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summarized.

  4. Modular heat exchanger

    DOE Patents [OSTI]

    Culver, Donald W.

    1978-01-01

    A heat exchanger for use in nuclear reactors includes a heat exchange tube bundle formed from similar modules each having a hexagonal shroud containing a large number of thermally conductive tubes which are connected with inlet and outlet headers at opposite ends of each module, the respective headers being adapted for interconnection with suitable inlet and outlet manifold means. In order to adapt the heat exchanger for operation in a high temperature and high pressure environment and to provide access to all tube ports at opposite ends of the tube bundle, a spherical tube sheet is arranged in sealed relation across the chamber with an elongated duct extending outwardly therefrom to provide manifold means for interconnection with the opposite end of the tube bundle.

  5. Heat exchange apparatus

    DOE Patents [OSTI]

    Degtiarenko, Pavel V.

    2003-08-12

    A heat exchange apparatus comprising a coolant conduit or heat sink having attached to its surface a first radial array of spaced-apart parallel plate fins or needles and a second radial array of spaced-apart parallel plate fins or needles thermally coupled to a body to be cooled and meshed with, but not contacting the first radial array of spaced-apart parallel plate fins or needles.

  6. Heat transfer and heat exchangers reference handbook

    SciTech Connect (OSTI)

    Not Available

    1991-01-15

    The purpose of this handbook is to provide Rocky Flats personnel with an understanding of the basic concepts of heat transfer and the operation of heat exchangers.

  7. Heat Exchangers for Solar Water Heating Systems | Department...

    Energy Savers [EERE]

    Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. |...

  8. Heat exchanger-accumulator

    DOE Patents [OSTI]

    Ecker, Amir L.

    1980-01-01

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

  9. Heat exchanger tube mounts

    DOE Patents [OSTI]

    Wolowodiuk, W.; Anelli, J.; Dawson, B.E.

    1974-01-01

    A heat exchanger in which tubes are secured to a tube sheet by internal bore welding is described. The tubes may be moved into place in preparation for welding with comparatively little trouble. A number of segmented tube support plates are provided which allow a considerable portion of each of the tubes to be moved laterally after the end thereof has been positioned in preparation for internal bore welding to the tube sheet. (auth)

  10. Heat exchange assembly

    DOE Patents [OSTI]

    Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

    2004-06-08

    A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

  11. Heat exchanger bypass test report

    SciTech Connect (OSTI)

    De Vries, M.L.

    1995-01-26

    This test report documents the results that were obtained while conducting the test procedure which bypassed the heat exchangers in the HC-21C sludge stabilization process. The test was performed on November 15, 1994 using WHC-SD-CP-TC-031, ``Heat Exchanger Bypass Test Procedure.`` The primary objective of the test procedure was to determine if the heat exchangers were contributing to condensation of moisture in the off-gas line. This condensation was observed in the rotameters. Also, a secondary objective was to determine if temperatures at the rotameters would be too high and damage them or make them inaccurate without the heat exchangers in place.

  12. Heat Exchangers for Solar Water Heating Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar collectors to the liquid or air used to heat water or a space. Heat exchangers can be made of steel, copper, bronze, stainless steel, aluminum, or cast iron. Solar heating systems usually use copper,

  13. High Temperature Heat Exchanger Project

    SciTech Connect (OSTI)

    Anthony E. Hechanova, Ph.D.

    2008-09-30

    The UNLV Research Foundation assembled a research consortium for high temperature heat exchanger design and materials compatibility and performance comprised of university and private industry partners under the auspices of the US DOE-NE Nuclear Hydrogen Initiative in October 2003. The objectives of the consortium were to conduct investigations of candidate materials for high temperature heat exchanger componets in hydrogen production processes and design and perform prototypical testing of heat exchangers. The initial research of the consortium focused on the intermediate heat exchanger (located between the nuclear reactor and hydrogen production plan) and the components for the hydrogen iodine decomposition process and sulfuric acid decomposition process. These heat exchanger components were deemed the most challenging from a materials performance and compatibility perspective

  14. Modular heat exchanger

    DOE Patents [OSTI]

    Giardina, Angelo R. [Marple Township, Delaware County, PA

    1981-03-03

    A shell and tube heat exchanger having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelpiped tube bundle moldules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending therethrough, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattice, each of which is situate d in a plane between the end support members. The intermediate support members constituting the several lattice extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates.

  15. Modular heat exchanger

    DOE Patents [OSTI]

    Giardina, A.R.

    1981-03-03

    A shell and tube heat exchanger is described having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelepiped tube bundle modules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending there through, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattices, each of which is situated in a plane between the end support members. The intermediate support members constituting the several lattices extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates. 12 figs.

  16. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect (OSTI)

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

    1998-07-01

    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.

  17. Heat exchanger using graphite foam

    DOE Patents [OSTI]

    Campagna, Michael Joseph; Callas, James John

    2012-09-25

    A heat exchanger is disclosed. The heat exchanger may have an inlet configured to receive a first fluid and an outlet configured to discharge the first fluid. The heat exchanger may further have at least one passageway configured to conduct the first fluid from the inlet to the outlet. The at least one passageway may be composed of a graphite foam and a layer of graphite material on the exterior of the graphite foam. The layer of graphite material may form at least a partial barrier between the first fluid and a second fluid external to the at least one passageway.

  18. Heat exchanger with ceramic elements

    DOE Patents [OSTI]

    Corey, John A.

    1986-01-01

    An annular heat exchanger assembly includes a plurality of low thermal growth ceramic heat exchange members with inlet and exit flow ports on distinct faces. A mounting member locates each ceramic member in a near-annular array and seals the flow ports on the distinct faces into the separate flow paths of the heat exchanger. The mounting member adjusts for the temperature gradient in the assembly and the different coefficients of thermal expansion of the members of the assembly during all operating temperatures.

  19. printed-circuit heat exchanger PCHE

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    printed-circuit heat exchanger PCHE - Sandia Energy Energy Search Icon Sandia Home ... SunShot Grand Challenge: Regional Test Centers printed-circuit heat exchanger PCHE Home...

  20. Heat exchanger and related methods

    SciTech Connect (OSTI)

    Turner, Terry D.; McKellar, Michael G.

    2015-12-22

    Heat exchangers include a housing having an inlet and an outlet and forming a portion of a transition chamber. A heating member may form another portion of the transition chamber. The heating member includes a first end having a first opening and a second end having a second opening larger than the first opening. Methods of conveying a fluid include supplying a first fluid into a transition chamber of a heat exchanger, supplying a second fluid into the transition chamber, and altering a state of a portion of the first fluid with the second fluid. Methods of sublimating solid particles include conveying a first fluid comprising a material in a solid state into a transition chamber, heating the material to a gaseous state by directing a second fluid through a heating member and mixing the first fluid and the second fluid.

  1. Ceramic heat exchanger

    DOE Patents [OSTI]

    LaHaye, Paul G.; Rahman, Faress H.; Lebeau, Thomas P. E.; Severin, Barbara K.

    1998-01-01

    A tube containment system. The tube containment system does not significantly reduce heat transfer through the tube wall. The contained tube is internally pressurized, and is formed from a ceramic material having high strength, high thermal conductivity, and good thermal shock resistance. The tube containment system includes at least one ceramic fiber braid material disposed about the internally pressurized tube. The material is disposed about the tube in a predetermined axial spacing arrangement. The ceramic fiber braid is present in an amount sufficient to contain the tube if the tube becomes fractured. The tube containment system can also include a plurality of ceramic ring-shaped structures, in contact with the outer surface of the tube, and positioned between the tube and the ceramic fiber braid material, and/or at least one transducer positioned within tube for reducing the internal volume and, therefore, the energy of any shrapnel resulting from a tube fracture.

  2. Ceramic heat exchanger

    DOE Patents [OSTI]

    LaHaye, P.G.; Rahman, F.H.; Lebeau, T.P.; Severin, B.K.

    1998-06-16

    A tube containment system is disclosed. The tube containment system does not significantly reduce heat transfer through the tube wall. The contained tube is internally pressurized, and is formed from a ceramic material having high strength, high thermal conductivity, and good thermal shock resistance. The tube containment system includes at least one ceramic fiber braid material disposed about the internally pressurized tube. The material is disposed about the tube in a predetermined axial spacing arrangement. The ceramic fiber braid is present in an amount sufficient to contain the tube if the tube becomes fractured. The tube containment system can also include a plurality of ceramic ring-shaped structures, in contact with the outer surface of the tube, and positioned between the tube and the ceramic fiber braid material, and/or at least one transducer positioned within tube for reducing the internal volume and, therefore, the energy of any shrapnel resulting from a tube fracture. 6 figs.

  3. Heat Exchangers for Solar Water Heating Systems | Department...

    Broader source: Energy.gov (indexed) [DOE]

    from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar...

  4. Heat exchanger for concentrating solar collectors and method for making the heat exchanger

    SciTech Connect (OSTI)

    Stultz, R.A.

    1983-08-09

    nment of the flow passages with the A heat exchanger assembly is disclosed for use with concentrating solar collectors of the type employing an elongated conduit for transporting a heat exchange fluid, the heat exchanger being positioned within an opening in the upper surface of the conduit and operating to transfer heat to the heat exchange fluid. The heat exchanger includes a plurality of stacked heat conducting heat exchanger plates having grooves oriented to form flow passage extending in the direction of fluid flow. The heat direction of heat exchange fluid flow. The grooved heat exchange plates may be fabricated by stamp from a sheet of heat conducting material to facilitate manufacturing of the heat exchanger. In another embodiment, the plates are positioned normal to the fluid flow direction with openings in the plates serving to form flow channels. The heat exchanger is usuable with collectors employing either photovoltaic cells or a solar radiation absorbing flat plate collector.

  5. Helically coiled tube heat exchanger

    SciTech Connect (OSTI)

    Harris, A.M.

    1981-08-18

    In a heat exchanger such as a steam generator for a nuclear reactor, two or more bundles of helically coiled tubes are arranged in series with the tubes in each bundle integrally continuing through the tube bundles arranged in series therewith. Pitch values for the tubing in any pair of tube bundles, taken transverse to the path of the reactor coolant flow about the tubes, are selected as a ratio of two unequal integers to permit efficient operation of each tube bundle while maintaining the various tube bundles of the heat exchanger within a compact envelope. Preferably, the helix angle and tube pitch parallel to the path of coolant flow are constant for all tubes in a single bundle so that the tubes are of approximately the same length within each bundle.

  6. "Heat Exchange Enhancing Insert" Inventors .--.. Andrei Khodak...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Heat Exchange Enhancing Insert" Inventors .--.. Andrei Khodak, Michael A. Jaworski A new shape of the heat enhancing insert is proposed. This device creates an impinging jet ...

  7. SODIUM-WATER HEAT EXCHANGER

    DOE Patents [OSTI]

    Simmons, W.R.; Koch, L.J.

    1962-04-17

    A heat exchanger comprising a tank for hot liquid and a plurality of concentric, double tubes for cool liquid extending vertically through the tank is described. These tubes are bonded throughout most of their length but have an unbonded portion at both ends. The inner tubes extend between headers located above and below the tanmk and the outer tubes are welded into tube sheets forming the top and bottom of the tank at locations in the unbonded portions of the tubes. (AEC)

  8. Fluidized bed heat exchanger utilizing angularly extending heat exchange tubes

    DOE Patents [OSTI]

    Talmud, Fred M.; Garcia-Mallol, Juan-Antonio

    1980-01-01

    A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided and includes a steam drum disposed adjacent the fluidized bed and a series of tubes connected at one end to the steam drum. A portion of the tubes are connected to a water drum and in the path of the air and the gaseous products of combustion exiting from the bed. Another portion of the tubes pass through the bed and extend at an angle to the upper surface of the bed.

  9. Heat Exchange, Additive Manufacturing, and Neutron Imaging

    SciTech Connect (OSTI)

    Geoghegan, Patrick

    2015-02-23

    Researchers at the Oak Ridge National Laboratory have captured undistorted snapshots of refrigerants flowing through small heat exchangers, helping them to better understand heat transfer in heating, cooling and ventilation systems.

  10. NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2008-09-01

    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

  11. Light weight and economical exhaust heat exchanger for waste...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Light weight and economical exhaust heat exchanger for waste heat recovery using mixed radiant and convective heat transfer Light weight and economical exhaust heat exchanger for ...

  12. Foundation Heat Exchanger Final Report: Demonstration, Measured...

    Office of Scientific and Technical Information (OSTI)

    humidity of a building, or supplying hot water and fresh outdoor air, must exchange ... over conventional space conditioning and water heating systems is primarily associated ...

  13. Heat exchanger for power generation equipment

    DOE Patents [OSTI]

    Nirmalan, Nirm Velumylm; Bowman, Michael John

    2005-06-14

    A heat exchanger for a turbine is provided wherein the heat exchanger comprises a heat transfer cell comprising a sheet of material having two opposed ends and two opposed sides. In addition, a plurality of concavities are disposed on a surface portion of the sheet of material so as to cause hydrodynamic interactions and affect a heat transfer rate of the turbine between a fluid and the concavities when the fluid is disposed over the concavities.

  14. Testing and plugging power plant heat exchangers

    SciTech Connect (OSTI)

    Sutor, F.

    1994-12-31

    Heat Exchanger tubes fail for any number of reasons including but certainly not limited to the cumulative effects of corrosion, erosion, thermal stress and fatigue. This presentation will attempt to identify the most common techniques for determining which tubes are leaking and then introduce the products in use to plug the leaking tubes. For the sake of time I will limit the scope of this presentation to include feedwater heaters and secondary system heat exchangers such as Hydrogen Coolers, Lube Oil Coolers, and nuclear Component Cooling Water, Emergency Cooling Water, Regenerative Heat Recovery heat exchangers.

  15. Heat exchanger device and method for heat removal or transfer

    DOE Patents [OSTI]

    Koplow, Jeffrey P

    2013-12-10

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

  16. Heat exchanger device and method for heat removal or transfer

    SciTech Connect (OSTI)

    Koplow, Jeffrey P.

    2015-12-08

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

  17. Heat exchanger device and method for heat removal or transfer

    DOE Patents [OSTI]

    Koplow, Jeffrey P.

    2012-07-24

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

  18. Heat exchanger device and method for heat removal or transfer

    SciTech Connect (OSTI)

    Koplow, Jeffrey P

    2015-03-24

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

  19. Heat exchanger with transpired, highly porous fins

    DOE Patents [OSTI]

    Kutscher, Charles F.; Gawlik, Keith

    2002-01-01

    The heat exchanger includes a fin and tube assembly with increased heat transfer surface area positioned within a hollow chamber of a housing to provide effective heat transfer between a gas flowing within the hollow chamber and a fluid flowing in the fin and tube assembly. A fan is included to force a gas, such as air, to flow through the hollow chamber and through the fin and tube assembly. The fin and tube assembly comprises fluid conduits to direct the fluid through the heat exchanger, to prevent mixing with the gas, and to provide a heat transfer surface or pathway between the fluid and the gas. A heat transfer element is provided in the fin and tube assembly to provide extended heat transfer surfaces for the fluid conduits. The heat transfer element is corrugated to form fins between alternating ridges and grooves that define flow channels for directing the gas flow. The fins are fabricated from a thin, heat conductive material containing numerous orifices or pores for transpiring the gas out of the flow channel. The grooves are closed or only partially open so that all or substantially all of the gas is transpired through the fins so that heat is exchanged on the front and back surfaces of the fins and also within the interior of the orifices, thereby significantly increasing the available the heat transfer surface of the heat exchanger. The transpired fins also increase heat transfer effectiveness of the heat exchanger by increasing the heat transfer coefficient by disrupting boundary layer development on the fins and by establishing other beneficial gas flow patterns, all at desirable pressure drops.

  20. Building Integrated Heat and Moisture Exchange | Department of...

    Energy Savers [EERE]

    Integrated Heat and Moisture Exchange Building Integrated Heat and Moisture Exchange 1 of 2 Building-integrated heat and moisture exchanger, the AirFlow(tm) Panel, installed for ...

  1. Circulating heat exchangers for oscillating wave engines and...

    Office of Scientific and Technical Information (OSTI)

    heat exchangers for oscillating wave engines and refrigerators Title: Circulating heat exchangers for oscillating wave engines and refrigerators An oscillating-wave engine or ...

  2. Supercritical Carbon Dioxide Turbo-Expander and Heat Exchangers...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Supercritical Carbon Dioxide Turbo-Expander and Heat Exchangers Supercritical Carbon Dioxide Turbo-Expander and Heat Exchangers This fact sheet describes a supercritical carbon ...

  3. High-Performance Refrigerator Using Novel Rotating Heat Exchanger |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy High-Performance Refrigerator Using Novel Rotating Heat Exchanger High-Performance Refrigerator Using Novel Rotating Heat Exchanger Rotating heat exchangers installed in appliances and heat pumps have the potentially to reduce energy costs and refrigerant charge in a compact space. Rotating heat exchangers installed in appliances and heat pumps have the potentially to reduce energy costs and refrigerant charge in a compact space. Sandia-developed rotating heat exchanger

  4. Miniaturized Air to Refrigerant Heat Exchangers

    Broader source: Energy.gov [DOE]

    This project is developing a miniaturized air-to-refrigerant heat exchanger that is more compact and more energy efficient than current market designs. The heat exchanger will feature at least 20% less volume, material volume, and approach temperature compared to current multiport flat tube designs, and it will be in production within five years. The heat exchanger, which acts as both an evaporator and a condenser, can be applied to commercial and residential air-conditioning or heat pump systems with various capacity scales. Prototype 1-kilowatt (kW) and 10 kW designs will be tested and then improved as necessary for final tests and demonstration in a 3-ton heat pump.

  5. Heat Exchanger With Internal Pin Elements

    DOE Patents [OSTI]

    Gerstmann, Joseph; Hannon, Charles L.

    2004-01-13

    A heat exchanger/heater comprising a tubular member having a fluid inlet end, a fluid outlet end and plurality of pins secured to the interior wall of the tube. Various embodiments additionally comprise a blocking member disposed concentrically inside the pins, such as a core plug or a baffle array. Also disclosed is a vapor generator employing an internally pinned tube, and a fluid-heater/heat-exchanger utilizing an outer jacket tube and fluid-side baffle elements, as well as methods for heating a fluid using an internally pinned tube.

  6. Heat exchanger with auxiliary cooling system

    DOE Patents [OSTI]

    Coleman, John H. (Salem Township, Westmoreland County, PA)

    1980-01-01

    A heat exchanger with an auxiliary cooling system capable of cooling a nuclear reactor should the normal cooling mechanism become inoperable. A cooling coil is disposed around vertical heat transfer tubes that carry secondary coolant therethrough and is located in a downward flow of primary coolant that passes in heat transfer relationship with both the cooling coil and the vertical heat transfer tubes. A third coolant is pumped through the cooling coil which absorbs heat from the primary coolant which increases the downward flow of the primary coolant thereby increasing the natural circulation of the primary coolant through the nuclear reactor.

  7. Heat exchanger restart evaluation. Revision 1

    SciTech Connect (OSTI)

    Morrison, J.M.; Hirst, C.W.; Lentz, T.F.

    1992-03-18

    On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4A was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the identified tube. The leaking tube was removed and examined metallurgically to determine the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time to any future events of this type. The results of these actions are summary herein.

  8. Experience with borehole heat exchangers in Switzerland

    SciTech Connect (OSTI)

    Rybach, L.; Hopkirk, R.J.

    1994-03-01

    Switzerland undertakes, like many other countries, great efforts to reduce its dependence from foreign fossil fuels. Indigenous sources of energy like the heat content of the subsurface are especially in focus, also due to environmental concern (greenhouse effect due to CO{sub 2} emissions). The most popular and technically advanced space heating system to use ground heat is the borehole heat exchanger (BHE). Shallow, coaxial or U-shaped BHEs are installed in 30-50 m deep, backfilled boreholes to extract, by closed-fluid circulation, heat from the ground. They feed the cold (evaporator) (e.g. floor panel) system to heat usually a single dwelling house. The energy supply for the heat exchanger comes from several sources: the vertical geothermal flux itself, the import of energy horizontally by conduction, advective transport with groundwater if present, and the compensating effect of heat exchange between the ground surface and the atmosphere. Multiple BHEs are installed for larger units like community buildings, etc. Since 1980, almost 5,000 such systems, using about 10,000 BHEs with a total length of more than 700,000 m have been installed in Switzerland. The BHE can be upscaled in order to be installed in otherwise abandoned deep boreholes (e.g., in {open_quotes}dry{close_quotes} geothermal or hydrocarbon exploratory holes). Experimental as well as theoretical studies have been pursued in Switzerland in the last 10 years to establish a sound technical and energy economics base for shallow and deep BHE systems.

  9. Energy absorber for sodium-heated heat exchanger

    DOE Patents [OSTI]

    Essebaggers, J.

    1975-12-01

    A heat exchanger is described in which water-carrying tubes are heated by liquid sodium and in which the results of accidental contact between the water and the sodium caused by failure of one or more of the water tubes is minimized. An energy absorbing chamber contains a compressible gas and is connected to the body of flowing sodium by a channel so that, in the event of a sodium-water reaction, products of the reaction will partially fill the energy absorbing chamber to attenuate the rise in pressure within the heat exchanger.

  10. Modeling particle deposition on HVAC heat exchangers

    SciTech Connect (OSTI)

    Siegel, J.A.; Nazaroff, W.W.

    2002-01-01

    Fouling of fin-and-tube heat exchangers by particle deposition leads to diminished effectiveness in supplying ventilation and air conditioning. This paper explores mechanisms that cause particle deposition on heat exchanger surfaces. We present a model that accounts for impaction, diffusion, gravitational settling, and turbulence. Simulation results suggest that some submicron particles deposit in the heat exchanger core, but do not cause significant performance impacts. Particles between 1 and 10 {micro}m deposit with probabilities ranging from 1-20% with fin edge impaction representing the dominant mechanism. Particles larger than 10 {micro}m deposit by impaction on refrigerant tubes, gravitational settling on fin corrugations, and mechanisms associated with turbulent airflow. The model results agree reasonably well with experimental data, but the deposition of larger particles at high velocities is underpredicted. Geometric factors, such as discontinuities in the fins, are hypothesized to be responsible for the discrepancy.

  11. Heat exchanger for coal gasification process

    DOE Patents [OSTI]

    Blasiole, George A.

    1984-06-19

    This invention provides a heat exchanger, particularly useful for systems requiring cooling of hot particulate solids, such as the separated fines from the product gas of a carbonaceous material gasification system. The invention allows effective cooling of a hot particulate in a particle stream (made up of hot particulate and a gas), using gravity as the motive source of the hot particulate. In a preferred form, the invention substitutes a tube structure for the single wall tube of a heat exchanger. The tube structure comprises a tube with a core disposed within, forming a cavity between the tube and the core, and vanes in the cavity which form a flow path through which the hot particulate falls. The outside of the tube is in contact with the cooling fluid of the heat exchanger.

  12. Miniaturized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Miniaturized Air-to-Refrigerant Heat Exchangers 2014 Building Technologies Office Peer Review Prof. Reinhard Radermacher, raderm@umd.edu University of Maryland College Park Project Summary Timeline: Start date: 03/01/2013 Planned end date: 02/29/2016 Key Milestones 1. Heat exchanger designs/process: 6/30/14 2. Fabrication/testing of 1 kW: 9/30/14 3. Fabrication/testing of 10 kW: 9/30/2015 Budget: Total DOE $ to date: $561K Total future DOE $: $489K Target Market/Audience: Residential and

  13. Sandwhiched Orb/Grid Heat Exchanger | Princeton Plasma Physics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sandwhiched OrbGrid Heat Exchanger The design basis of the heat exchanger is that the most efficient geometrical shape to thermally stabilize during exposure to heat or to neutron ...

  14. Carbon nanotube heat-exchange systems

    DOE Patents [OSTI]

    Hendricks, Terry Joseph; Heben, Michael J.

    2008-11-11

    A carbon nanotube heat-exchange system (10) and method for producing the same. One embodiment of the carbon nanotube heat-exchange system (10) comprises a microchannel structure (24) having an inlet end (30) and an outlet end (32), the inlet end (30) providing a cooling fluid into the microchannel structure (24) and the outlet end (32) discharging the cooling fluid from the microchannel structure (24). At least one flow path (28) is defined in the microchannel structure (24), fluidically connecting the inlet end (30) to the outlet end (32) of the microchannel structure (24). A carbon nanotube structure (26) is provided in thermal contact with the microchannel structure (24), the carbon nanotube structure (26) receiving heat from the cooling fluid in the microchannel structure (24) and dissipating the heat into an external medium (19).

  15. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon

    2001-04-17

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  16. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, D.G.

    1993-11-09

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices. 11 figures.

  17. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David G.

    1993-01-01

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  18. Heat exchanger containing a component capable of discontinuous movement

    DOE Patents [OSTI]

    Wilson, David Gordon

    2002-01-01

    Regenerative heat exchangers are described for transferring heat between hot and cold fluids. The heat exchangers have seal-leakage rates significantly less than those of conventional regenerative heat exchangers because the matrix is discontinuously moved and is releasably sealed while in a stationary position. Both rotary and modular heat exchangers are described. Also described are methods for transferring heat between a hot and cold fluid using the discontinuous movement of matrices.

  19. Comparative analysis of compact heat exchangers for application as the intermediate heat exchanger for advanced nuclear reactors

    SciTech Connect (OSTI)

    Bartel, N.; Chen, M.; Utgikar, V. P.; Sun, X.; Kim, I. -H.; Christensen, R.; Sabharwall, P.

    2015-04-04

    A comparative evaluation of alternative compact heat exchanger designs for use as the intermediate heat exchanger in advanced nuclear reactor systems is presented in this article. Candidate heat exchangers investigated included the Printed circuit heat exchanger (PCHE) and offset strip-fin heat exchanger (OSFHE). Both these heat exchangers offer high surface area to volume ratio (a measure of compactness [m2/m3]), high thermal effectiveness, and overall low pressure drop. Helium–helium heat exchanger designs for different heat exchanger types were developed for a 600 MW thermal advanced nuclear reactor. The wavy channel PCHE with a 15° pitch angle was found to offer optimum combination of heat transfer coefficient, compactness and pressure drop as compared to other alternatives. The principles of the comparative analysis presented here will be useful for heat exchanger evaluations in other applications as well.

  20. Comparative analysis of compact heat exchangers for application as the intermediate heat exchanger for advanced nuclear reactors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bartel, N.; Chen, M.; Utgikar, V. P.; Sun, X.; Kim, I. -H.; Christensen, R.; Sabharwall, P.

    2015-04-04

    A comparative evaluation of alternative compact heat exchanger designs for use as the intermediate heat exchanger in advanced nuclear reactor systems is presented in this article. Candidate heat exchangers investigated included the Printed circuit heat exchanger (PCHE) and offset strip-fin heat exchanger (OSFHE). Both these heat exchangers offer high surface area to volume ratio (a measure of compactness [m2/m3]), high thermal effectiveness, and overall low pressure drop. Helium–helium heat exchanger designs for different heat exchanger types were developed for a 600 MW thermal advanced nuclear reactor. The wavy channel PCHE with a 15° pitch angle was found to offer optimummore » combination of heat transfer coefficient, compactness and pressure drop as compared to other alternatives. The principles of the comparative analysis presented here will be useful for heat exchanger evaluations in other applications as well.« less

  1. Preliminary SP-100/Stirling heat exchanger designs

    SciTech Connect (OSTI)

    Schmitz, P.; Tower, L.; Dawson, R.; Blue, B.; Dunn, P.

    1994-09-01

    Analytic modeling of several heat exchanger concepts to couple the SP-100 nuclear reactor lithium loop and the Space Stirling Power Convertor (SSPC) was performed. Four 25 kWe SSPC`s are used to produce the required 100 kW of electrical power. This design work focused on the interface between a single SSPC and the primary lithium loop. Manifolding to separate and collect the four channel flow was not modeled. This work modeled two separate types of heat exchanger interfaces (conductive coupling and radiative coupling) to explore their relative advantages and disadvantages. The minimum mass design of the conductively coupled concepts was 18 kg or 0.73 kg/kWe for a single 25 kWe convertor. The minimum mass radiatively coupled concept was 41 kg or 1.64 kg/kWe. The direct conduction heat exchanger provides a lighter weight system because of its ability to operate the Stirling convertor evaporator at higher heat fluxes than those attainable by the radiatively coupled systems. Additionally the conductively coupled concepts had relatively small volumes and provide potentially simpler assembly. Their disadvantages were the tight tolerances and material joining problems associated with this refractory to superalloy interface. The advantages of the radiatively coupled designs were the minimal material interface problems.

  2. Triple loop heat exchanger for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A triple loop heat exchanger for an absorption refrigeration system is disclosed. The triple loop heat exchanger comprises portions of a strong solution line for conducting relatively hot, strong solution from a generator to a solution heat exchanger of the absorption refrigeration system, conduit means for conducting relatively cool, weak solution from the solution heat exchanger to the generator, and a bypass system for conducting strong solution from the generator around the strong solution line and around the solution heat exchanger to an absorber of the refrigeration system when strong solution builds up in the generator to an undesirable level. The strong solution line and the conduit means are in heat exchange relationship with each other in the triple loop heat exchanger so that, during normal operation of the refrigeration system, heat is exchanged between the relatively hot, strong solution flowing through the strong solution line and the relatively cool, weak solution flowing through the conduit means. Also, the strong solution line and the bypass system are in heat exchange relationship in the triple loop heat exchanger so that if the normal flow path of relatively hot, strong solution flowing from the generator to an absorber is blocked, then this relatively, hot strong solution which will then be flowing through the bypass system in the triple loop heat exchanger, is brought into heat exchange relationship with any strong solution which may have solidified in the strong solution line in the triple loop heat exchanger to thereby aid in desolidifying any such solidified strong solution.

  3. Liquid Metal Heat Exchanger for Geologic Deposits - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Liquid Metal Heat Exchanger for Geologic Deposits Oak Ridge National Laboratory Contact ... The apparatus provides more efficient heat transfer than existing technologies for ...

  4. Demonstration and Performance Monitoring of Foundation Heat Exchangers...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstration and Performance Monitoring of Foundation Heat Exchangers in Low Load, High Performance Research Homes Demonstration and Performance Monitoring of Foundation Heat ...

  5. 1-MWe heat exchangers for OTEC. Final acceptance document

    SciTech Connect (OSTI)

    Snyder, J.E.

    1980-06-19

    Acceptance documents for major units of 1 MWe OTEC heat exchangers, including condensers and evaporators, are provided. Included are a transportation plan for the heat exchangers and design specifications for the phase separator. (LEW)

  6. Building-Integrated Heat & Moisture Exchange

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Building-Integrated Heat & Moisture Exchange 2014 Building Technologies Office Peer Review John E. Breshears jbreshears@architecturalapplications.com Architectural Applications Project Summary Timeline: Start date: October, 2012 Planned end date: August, 2014 Key Milestones Mid- & Full-scale Lab Tests; June, 2013 Full-scale Demo; January, 2014 System Documentation; July, 2014 Budget: Total DOE $ to date: $1,037,812 Total future DOE $: $0 (committed to date) Target Market/Audience:

  7. Building-Integrated Heat & Moisture Exchange

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Building-Integrated Heat & Moisture Exchange 2016 Building Technologies Office Peer Review John Breshears, President Architectural Applications jbreshears@architecturalapplications.com 2 Project Summary Timeline: Start date: June 17, 2011 Planned end date: July 27, 2016 Key Milestones 1: Demo. Manufacturing at Target Cost July'16 2: Alternate Design At 8% Lower Cost July'17 3: Assembly w/ 28% Fewer Parts July'17 Budget: Tot. Project $ to Date: * DOE: $1288590 * Cost Share: $878833 Total

  8. Optimizing PT Arun LNG main heat exchanger

    SciTech Connect (OSTI)

    Irawan, B.

    1995-12-01

    The capacity of a LNG liquefaction unit has been increased by upgrading the refrigeration system, without making changes to the main heat exchanger (MHE). It is interesting, that after all modifications were completed, a higher refrigerant circulation alone could not increase LNG production. However, by optimizing the refrigerant component ratio, the UA of the MHE increased and LNG production improved. This technical evaluation will provide recommendations and show how the evaluation of the internal temperature profile helped optimize the MHE operating conditions.

  9. Radial Flow Bearing Heat Exchanger | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Radial Flow Bearing Heat Exchanger Radial Flow Bearing Heat Exchanger Sandia's Radial Flow Heat Exchanger Sandia's Radial Flow Heat Exchanger Lead Performer: Sandia National Laboratories - Albuquerque, NM Partners: -- Tribologix - Golden, CO -- United Technologies Research Center - East Hartford, CT -- University of Maryland - College Park, MD -- Oak Ridge National Laboratory - Oak Ridge, TN -- Whirlpool - Benton Harbor, MI -- Optimized Thermal Systems - College Park, MD DOE Funding: $5,472,285

  10. OXIDE DISPERSION-STRENGTHENED HEAT EXCHANGER TUBING

    SciTech Connect (OSTI)

    Harper, Mark A.

    2001-11-06

    Oxide dispersion strengthened (ODS) alloys (e.g. the INCOLOY{reg_sign} MA956 alloy) are known for their excellent high temperature properties and are prime candidate materials for the construction of very high temperature heat exchangers that will be used in Vision 21 power plants. The main limitation of these materials is their poor weldability. Commercially available ODS tubing also tends to exhibit relatively poor circumferential creep strength due to current processing practices resulting in a fine grain size in the transverse direction. Thus far, these two characteristics of the ODS tubing have restricted its use to mostly non-pressure containing applications. The objectives of this program are to develop: (a) an MA956 tube with sufficient circumferential creep strength for long term use as heat exchanger tubing for very high temperatures; (b) a welding technique(s) for producing adequate joints between an MA956 tube and an MA956 tube, and an MA956 tube and an INCONEL 601 tube; (c) the bending strain limits, below which recrystallization will not occur in a MA956 tube during normal operation; and (d) the high temperature corrosion limits for the MA956 alloy with respect to working-fluid side and fireside environments. Also, this program seeks to generate data for use by heat exchanger designers and the ASME Boiler and Pressure Vessel Code, and perform an analysis of the mechanical property, tube bending, and corrosion data in order to determine the implications on the design of a very high temperature heat exchanger (T>1093 C/2000 F). After one year, work is currently being conducted on increasing the circumferential strength of a MA956 tube, developing joining techniques for this material, determining the tube bending strain limits, and establishing the high temperature corrosion parameters for the MA956 alloy in environments expected to be present in Vision 21 power plants. Work in these areas will is continuing into the next fiscal year, with success

  11. Technology Solutions Case Study: Foundation Heat Exchanger, Oak Ridge, Tennessee

    SciTech Connect (OSTI)

    2014-03-01

    The foundation heat exchanger, developed by Oak Ridge National Laboratory, is a new concept for a cost-effective horizontal ground heat exchanger that can be connected to water-to-water or water-to-air heat pump systems for space conditioning as well as domestic water heating.

  12. Acoustic resonance in heat exchanger tube bundles

    SciTech Connect (OSTI)

    Blevins, R.D. )

    1994-02-01

    A series of experiments has been made on aeroacoustic tones produced by flow over tubes in a duct. The sound is characterized by the onset of a loud and persistent acoustic resonance. The acoustic resonance occurs at the frequency of the acoustic modes. The magnitude and extent of the resonance are functions of tube pattern and tube pitch. The sound levels increase in proportion with Mach number, dynamic head and pressure drop. A design procedure for predicting the magnitude of the sound within the tube array is presented. Methods of resonance avoidance are illustrated. An example is made for a large petrochemical heat exchanger.

  13. Miniaturized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Miniaturized Air-to-Refrigerant Heat Exchangers 2015 Building Technologies Office Peer Review Reinhard Radermacher raderm@umd.edu 20%+ Better University of Maryland College Park Project Summary Timeline: Start date: 3/1/2013 Planned end date: 2/29/2016 Key Milestones 1. Design optimization, 3/30/14 2. Fabrication/testing, 1kW prototype, 1/30/2015 3. Fabrication/testing, 10kW prototype, 9/30/2015 Budget: Total Budget: $1500K Total UMD: $1050K Total DOE $ to date for UMD: $881K Total future DOE $

  14. Minituraized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Miniaturized Air-to-Refrigerant Heat Exchangers 2016 Building Technologies Office Peer Review Reinhard Radermacher raderm@umd.edu University of Maryland College Park Better 20%+ 2 Project Summary Timeline: Start date: 3/1/2013 Original end date: 2/29/2016 Revised end date: 10/30/2016 Key Milestones 1. Design optimization, 3/30/14 2. Fabrication/testing, 1kW prototype, 6/30/2015 3. Fabrication/testing, 10kW prototype, 1/30/2016 Budget: Total Budget: $1500K Total UMD: $1050K Total DOE $ to date

  15. Low-Cost Microchannel Heat Exchanger

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ALTEX TECHNOLOGIES CORPORATION Low-Cost Microchannel Heat Exchanger DOE Grant DE-EE0004541 2013-2014 Dr. John T. Kelly Altex Technologies Corporation 244 Sobrante Way Sunnyvale, CA 94086 Phone: 408-328-8302 E-mail: john@altextech.com U.S. DOE Advanced Manufacturing Office PEER Review Meeting Washington, D.C. May 6-7, 2014 This presentation does not contain any proprietary, confidential, or otherwise restricted information. ALTEX TECHNOLOGIES CORPORATION Project Objectives  Define and test low

  16. Heat exchanger for a Stirling engine

    SciTech Connect (OSTI)

    Fujiwara, M.; Nomaguchi, T.; Kazumoto, Y.; Tsuchino, K.; Kawajiri, K.; Hisamori, Y.

    1987-05-05

    A heat exchanger is described for a Stirling engine comprising: a domed cylinder having a domed portion and a cylindrical portion. The domed cylinder serves as a high-temperature cylinder and a regenerator housing of the Stirling engine; a cylindrical inner liner which is coaxially disposed inside the domed cylinder and which divides the inside of the domed cylinder into an expansion space inside of the inner liner and a regenerator space between the outer surface of the inner liner and the inner surface of the cylindrical portion of the domed cylinder.

  17. DESIGN OF A COMPACT HEAT EXCHANGER FOR HEAT RECUPERATION FROM A HIGH TEMPERATURE ELECTROLYSIS SYSTEM

    SciTech Connect (OSTI)

    G. K. Housley; J.E. O'Brien; G.L. Hawkes

    2008-11-01

    Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.

  18. Heat extraction from salinity-gradient solar ponds using heat pipe heat exchangers

    SciTech Connect (OSTI)

    Tundee, Sura; Terdtoon, Pradit; Sakulchangsatjatai, Phrut; Singh, Randeep; Akbarzadeh, Aliakbar

    2010-09-15

    This paper presents the results of experimental and theoretical analysis on the heat extraction process from solar pond by using the heat pipe heat exchanger. In order to conduct research work, a small scale experimental solar pond with an area of 7.0 m{sup 2} and a depth of 1.5 m was built at Khon Kaen in North-Eastern Thailand (16 27'N102 E). Heat was successfully extracted from the lower convective zone (LCZ) of the solar pond by using a heat pipe heat exchanger made from 60 copper tubes with 21 mm inside diameter and 22 mm outside diameter. The length of the evaporator and condenser section was 800 mm and 200 mm respectively. R134a was used as the heat transfer fluid in the experiment. The theoretical model was formulated for the solar pond heat extraction on the basis of the energy conservation equations and by using the solar radiation data for the above location. Numerical methods were used to solve the modeling equations. In the analysis, the performance of heat exchanger is investigated by varying the velocity of inlet air used to extract heat from the condenser end of the heat pipe heat exchanger (HPHE). Air velocity was found to have a significant influence on the effectiveness of heat pipe heat exchanger. In the present investigation, there was an increase in effectiveness by 43% as the air velocity was decreased from 5 m/s to 1 m/s. The results obtained from the theoretical model showed good agreement with the experimental data. (author)

  19. Heat exchanger for fuel cell power plant reformer

    DOE Patents [OSTI]

    Misage, Robert; Scheffler, Glenn W.; Setzer, Herbert J.; Margiott, Paul R.; Parenti, Jr., Edmund K.

    1988-01-01

    A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fuel cell reaction. The four temperature adjustments are accomplished in a single heat exchanger with only three heat transfer cores. The heat exchanger is preheated by circulating coolant and purge steam from the power section during startup of the latter.

  20. Heat exchanger and water tank arrangement for passive cooling system

    DOE Patents [OSTI]

    Gillett, James E. (Greensburg, PA); Johnson, F. Thomas (Baldwin Boro, PA); Orr, Richard S. (Pittsburgh, PA); Schulz, Terry L. (Murrysville Boro, PA)

    1993-01-01

    A water storage tank in the coolant water loop of a nuclear reactor contains a tubular heat exchanger. The heat exchanger has tubesheets mounted to the tank connections so that the tubesheets and tubes may be readily inspected and repaired. Preferably, the tubes extend from the tubesheets on a square pitch and then on a rectangular pitch therebetween. Also, the heat exchanger is supported by a frame so that the tank wall is not required to support all of its weight.

  1. Advanced heat exchanger development for molten salts

    SciTech Connect (OSTI)

    Sabharwall, Piyush; Clark, Denis; Glazoff, Michael; Zheng, Guiqiu; Sridharan, Kumar; Anderson, Mark

    2014-12-01

    This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, which show corrosion resistance to molten salt at nominal operating temperatures up to 700C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet material in Hastelloy N were corrosion tested in?58 mol% KF and 42 mol% ZrF4 at 650, 700, and 850C for 200, 500, and 1,000 hours. Corrosion rates found were similar between welded and nonwelded materials, typically <10 mils per year. For materials of construction, nickel and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of contaminant type and alloy composition with respect to chromium and carbon to better define the optimal chromium and carbon composition, independent of galvanic or differential solubility effects. Also presented is the division of the nuclear reactor and high temperature components per ASME standards, along with design requirements for a subcritical Rankine power cycle heat exchanger that has to overcome pressure difference of about 17 MPa.

  2. Advanced heat exchanger development for molten salts

    SciTech Connect (OSTI)

    Sabharwall, Piyush; Clark, Denis; Glazoff, Michael; Zheng, Guiqiu; Sridharan, Kumar; Anderson, Mark

    2014-12-01

    This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, which show corrosion resistance to molten salt at nominal operating temperatures up to 700°C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet material in Hastelloy N were corrosion tested in?58 mol% KF and 42 mol% ZrF4 at 650, 700, and 850°C for 200, 500, and 1,000 hours. Corrosion rates found were similar between welded and nonwelded materials, typically <10 mils per year. For materials of construction, nickel and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of contaminant type and alloy composition with respect to chromium and carbon to better define the optimal chromium and carbon composition, independent of galvanic or differential solubility effects. Also presented is the division of the nuclear reactor and high temperature components per ASME standards, along with design requirements for a subcritical Rankine power cycle heat exchanger that has to overcome pressure difference of about 17 MPa.

  3. Advanced heat exchanger development for molten salts

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sabharwall, Piyush; Clark, Denis; Glazoff, Michael; Zheng, Guiqiu; Sridharan, Kumar; Anderson, Mark

    2014-12-01

    This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, which show corrosion resistance to molten salt at nominal operating temperatures up to 700°C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet materialmore » in Hastelloy N were corrosion tested in?58 mol% KF and 42 mol% ZrF4 at 650, 700, and 850°C for 200, 500, and 1,000 hours. Corrosion rates found were similar between welded and nonwelded materials, typically <10 mils per year. For materials of construction, nickel and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of contaminant type and alloy composition with respect to chromium and carbon to better define the optimal chromium and carbon composition, independent of galvanic or differential solubility effects. Also presented is the division of the nuclear reactor and high temperature components per ASME standards, along with design requirements for a subcritical Rankine power cycle heat exchanger that has to overcome pressure difference of about 17 MPa.« less

  4. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

    DOE Patents [OSTI]

    Koplow, Jeffrey P.

    2016-02-16

    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.

  5. Project Profile: High-Temperature Particle Heat Exchanger for...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in a turbine to generate electricity. Industry experience with similar heat exchangers is limited to lower pressures, lower temperatures, or alternative fluids like steam or ...

  6. Building-Integrated Heat & Moisture Exchange (STTR Phase 1 and...

    Office of Environmental Management (EM)

    -- ETH Zurich - Zurich, Switzerland -- Membrane Technology & Research Inc. - Newark, CA ... Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Membrane Technology Workshop ...

  7. Building Integrated Heat and Moisture Exchange | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Building-integrated heat and moisture exchanger, the AirFlow(tm) Panel, installed for evaluation at Lawrence Berkeley National Lab. Image: Architectural Applications 2 of 2 A ...

  8. Two-Phase Heat Exchanger for Power Electronics Cooling - Energy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Find More Like This Return to Search Two-Phase Heat Exchanger for Power Electronics ... Heat dissipation is a limiting factor in reducing the size and cost of the power ...

  9. Universal Monitor (UM) for OTEC compact heat exchangers

    SciTech Connect (OSTI)

    Kuzay, T.M.

    1981-09-01

    Universal Monitor (UM), is a device-independent concept to measure, with precision, the initiation and progression of fouling in any given OTEC Compact Heat Exchanger model with or without the application of countermeasures. Design description and supporting analyses for the Universal Monitor for OTEC Compact Heat Exchangers are presented.

  10. Circulating heat exchangers for oscillating wave engines and refrigerators

    DOE Patents [OSTI]

    Swift, Gregory W.; Backhaus, Scott N.

    2003-10-28

    An oscillating-wave engine or refrigerator having a regenerator or a stack in which oscillating flow of a working gas occurs in a direction defined by an axis of a trunk of the engine or refrigerator, incorporates an improved heat exchanger. First and second connections branch from the trunk at locations along the axis in selected proximity to one end of the regenerator or stack, where the trunk extends in two directions from the locations of the connections. A circulating heat exchanger loop is connected to the first and second connections. At least one fluidic diode within the circulating heat exchanger loop produces a superimposed steady flow component and oscillating flow component of the working gas within the circulating heat exchanger loop. A local process fluid is in thermal contact with an outside portion of the circulating heat exchanger loop.

  11. Self-defrosting recuperative air-to-air heat exchanger

    DOE Patents [OSTI]

    Drake, Richard L.

    1993-01-01

    A heat exchanger includes a stationary spirally or concentrically wound heat exchanger core with rotating baffles on upper and lower ends thereof. The rotating baffles include rotating inlets and outlets which are in communication with respective fixed inlets and outlets via annuli. The rotation of the baffles causes a concurrent rotation of the temperature distribution within the stationary exchanger core, thereby preventing frost build-up in some applications and preventing the formation of hot spots in other applications.

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

    SciTech Connect (OSTI)

    Skupinski, R.C.; Tower, L.K.; Madi, F.J.; Brusk, K.D.

    1993-04-01

    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.

  13. Evaluation of porous media heat exchangers for fusion applications

    SciTech Connect (OSTI)

    Rosenfeld, J.H.; Lindemuth, J.E.; North, M.T.; Watson, R.D.; Youchison, D.L.; Goulding, R.H.

    1996-07-01

    Several types of porous media heat exchangers are being evaluated for use in fusion applications. Broadly, these devices can be classified as capillary-pumped (heat pipes) or mechanically-pumped heat exchangers. Monel/water thermosyphon heat pipes with a porous metal wick are being evaluated for use in Faraday shields. A subscale prototype has been fabricated, and initial tests at Oak Ridge National Laboratory have shown favorable results. Alkali metal heat pipes have demonstrated absorbed heat flux capability of over 1000 MW/m{sup 2}. An advanced gyrotron microwave cavity is being developed that uses water cooling in a mechanically-pumped copper porous metal heat exchanger. Tests on a prototype demonstrated absorbed heat flux capability in excess of 100 MW/m{sup 2}. Porous metal heat exchangers with helium, water, or liquid metal coolants are being evaluated for plasma-facing component cooling. Tests on a helium/copper porous metal heat exchanger demonstrated absorbed heat flux capability in excess of 15 MW/m{sup 2}. Applications, conceptual designs, fabricated hardware, and test results are summarized. 22 refs., 5 figs., 2 tabs.

  14. Direct-contact closed-loop heat exchanger

    DOE Patents [OSTI]

    Berry, Gregory F. (Naperville, IL); Minkov, Vladimir (Skokie, IL); Petrick, Michael (Joliet, IL)

    1984-01-01

    A high temperature heat exchanger with a closed loop and a heat transfer liquid within the loop, the closed loop having a first horizontal channel with inlet and outlet means for providing direct contact of a first fluid at a first temperature with the heat transfer liquid, a second horizontal channel with inlet and outlet means for providing direct contact of a second fluid at a second temperature with the heat transfer liquid, and means for circulating the heat transfer liquid.

  15. Comparison of natural convection heat exchangers for solar water heating systems

    SciTech Connect (OSTI)

    Davidson, J.; Liu, W.

    1998-09-15

    Thermosyphon heat exchangers are used in indirect solar water heating systems to avoid using a pump to circulate water from the storage tank to the heat exchanger. In this study, the authors consider the effect of heat exchanger design on system performance. They also compare performance of a system with thermosyphon flow to the same system with a 40W pump in the water loop. In the first part of the study, the authors consider the impact of heat exchanger design on the thermal performance of both one- and two-collector solar water heaters. The comparison is based on Solar Rating and Certification Corporation (SRCC) OG300 simulations. The thermosyphon heat exchangers considered are (1) a one-pass, double wall, 0.22 m{sup 2}, four tube-in-shell heat exchanger manufactured by AAA Service and Supply, Inc., (the Quad-Rod); (2) a two-pass, double wall, 0.2 m{sup 2}, tube-in-shell made by Heliodyne, Inc., but not intended for commercial development; (3) a one-pass, single wall, 0.28 m{sup 2}, 31 tube-in-shell heat exchanger from Young Radiator Company, and (4) a one-pass single-wall, 0.61 m{sup 2}, four coil-in-shell heat exchanger made by ThermoDynamics Ltd. The authors compare performance of the systems with thermosyphon heat exchangers to a system with a 40 W pump used with the Quad-Rod heat exchanger. In the second part of the study, the effects of reducing frictional losses through the heat exchanger and/or the pipes connecting the heat exchanger to the storage tank, and increasing heat transfer area are evaluated in terms of OG300 ratings.

  16. Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump

    DOE Patents [OSTI]

    Phillips, Benjamin A.; Zawacki, Thomas S.; Marsala, Joseph

    1994-11-29

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use the working solution of the absorption system for the heat transfer medium.

  17. Microchannel crossflow fluid heat exchanger and method for its fabrication

    DOE Patents [OSTI]

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

    1982-08-31

    A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

  18. Microchannel crossflow fluid heat exchanger and method for its fabrication

    DOE Patents [OSTI]

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

    1985-05-14

    A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance. 9 figs.

  19. Microchannel crossflow fluid heat exchanger and method for its fabrication

    DOE Patents [OSTI]

    Swift, Gregory W.; Migliori, Albert; Wheatley, John C.

    1985-01-01

    A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

  20. Acoustically enhanced heat exchange and drying apparatus

    DOE Patents [OSTI]

    Bramlette, T.T.; Keller, J.O.

    1987-07-10

    A heat transfer drying apparatus includes an acoustically augmented heat transfer chamber for receiving material to be dried. The chamber includes a first heat transfer gas inlet, a second heat transfer gas inlet, a material inlet, and a gas outlet which also serves as a dried material and gas outlet. A non-pulsing first heat transfer gas source provides a first drying gas to the acoustically augmented heat transfer chamber through the first heat transfer gas inlet. A valveless, continuous second heat transfer gas source provides a second drying gas to the acoustically augmented heat transfer chamber through the second heat transfer gas inlet. The second drying gas also generates acoustic waves which bring about acoustical coupling with the gases in the acoustically augmented heat transfer chamber. The second drying gas itself oscillates at an acoustic frequency of approximately 180 Hz due to fluid mechanical motion in the gas. The oscillations of the second heat transfer gas coupled to the first heat transfer gas in the acoustically augmented heat transfer chamber enhance heat and mass transfer by convection within the chamber. 3 figs.

  1. SILICON CARBIDE CERAMICS FOR COMPACT HEAT EXCHANGERS

    SciTech Connect (OSTI)

    DR. DENNIS NAGLE; DR. DAJIE ZHANG

    2009-03-26

    Silicon carbide (SiC) materials are prime candidates for high temperature heat exchangers for next generation nuclear reactors due to their refractory nature and high thermal conductivity at elevated temperatures. This research has focused on demonstrating the potential of liquid silicon infiltration (LSI) for making SiC to achieve this goal. The major advantage of this method over other ceramic processing techniques is the enhanced capability of making high dense, high purity SiC materials in complex net shapes. For successful formation of net shape SiC using LSI techniques, the carbon preform reactivity and pore structure must be controlled to allow the complete infiltration of the porous carbon structure which allows complete conversion of the carbon to SiC. We have established a procedure for achieving desirable carbon properties by using carbon precursors consisting of two readily available high purity organic materials, crystalline cellulose and phenolic resin. Phenolic resin yields a glassy carbon with low chemical reactivity and porosity while the cellulose carbon is highly reactive and porous. By adjusting the ratio of these two materials in the precursor mixtures, the properties of the carbons produced can be controlled. We have identified the most favorable carbon precursor composition to be a cellulose resin mass ratio of 6:4 for LSI formation of SiC. The optimum reaction conditions are a temperature of 1800 C, a pressure of 0.5 Torr of argon, and a time of 120 minutes. The fully dense net shape SiC material produced has a density of 2.96 g cm{sup -3} (about 92% of pure SiC) and a SiC volume fraction of over 0.82. Kinetics of the LSI SiC formation process was studied by optical microscopy and quantitative digital image analysis. This study identified six reaction stages and provided important understanding of the process. Although the thermal conductivity of pure SiC at elevated temperatures is very high, thermal conductivities of most commercial Si

  2. Heat exchanger and water tank arrangement for passive cooling system

    DOE Patents [OSTI]

    Gillett, J.E.; Johnson, F.T.; Orr, R.S.; Schulz, T.L.

    1993-11-30

    A water storage tank in the coolant water loop of a nuclear reactor contains a tubular heat exchanger. The heat exchanger has tube sheets mounted to the tank connections so that the tube sheets and tubes may be readily inspected and repaired. Preferably, the tubes extend from the tube sheets on a square pitch and then on a rectangular pitch there between. Also, the heat exchanger is supported by a frame so that the tank wall is not required to support all of its weight. 6 figures.

  3. Low Cost Polymer heat Exchangers for Condensing Boilers

    SciTech Connect (OSTI)

    Butcher, Thomas; Trojanowski, Rebecca; Wei, George; Worek, Michael

    2015-09-30

    Work in this project sought to develop a suitable design for a low cost, corrosion resistant heat exchanger as part of a high efficiency condensing boiler. Based upon the design parameters and cost analysis several geometries and material options were explored. The project also quantified and demonstrated the durability of the selected polymer/filler composite under expected operating conditions. The core material idea included a polymer matrix with fillers for thermal conductivity improvement. While the work focused on conventional heating oil, this concept could also be applicable to natural gas, low sulfur heating oil, and biodiesel- although these are considered to be less challenging environments. An extruded polymer composite heat exchanger was designed, built, and tested during this project, demonstrating technical feasibility of this corrosion-resistant material approach. In such flue gas-to-air heat exchangers, the controlling resistance to heat transfer is in the gas-side convective layer and not in the tube material. For this reason, the lower thermal conductivity polymer composite heat exchanger can achieve overall heat transfer performance comparable to a metal heat exchanger. However, with the polymer composite, the surface temperature on the gas side will be higher, leading to a lower water vapor condensation rate.

  4. A simplified model for heat transfer in heat exchangers and stack plates for thermoacoustic devices

    SciTech Connect (OSTI)

    Chen, Y.; Herman, C.

    1999-07-01

    A simplified model of heat transfer in heat exchangers and stack plates of thermoacoustic devices was developed. The model took advantage of previous results regarding the thermal behavior of the thermoacoustic core for investigations of the performance of heat exchangers attached to the core. Geometrical and operational parameters as well as thermophysical properties of the heat exchangers, the plate, and the working medium were organized into dimensionless groups that allowed to account for their impact on the performance of the heat exchangers. Numerical simulations with the model were carried out. Nonlinear temperature distributions and heat fluxes near the edge of the stack plate were observed. Effects of different parameters on the thermal performance of the heat exchangers were investigated.

  5. Heat exchanger for reactor core and the like

    DOE Patents [OSTI]

    Kaufman, Jay S.; Kissinger, John A.

    1986-01-01

    A compact bayonet tube type heat exchanger which finds particular application as an auxiliary heat exchanger for transfer of heat from a reactor gas coolant to a secondary fluid medium. The heat exchanger is supported within a vertical cavity in a reactor vessel intersected by a reactor coolant passage at its upper end and having a reactor coolant return duct spaced below the inlet passage. The heat exchanger includes a plurality of relatively short length bayonet type heat exchange tube assemblies adapted to pass a secondary fluid medium therethrough and supported by primary and secondary tube sheets which are releasibly supported in a manner to facilitate removal and inspection of the bayonet tube assemblies from an access area below the heat exchanger. Inner and outer shrouds extend circumferentially of the tube assemblies and cause the reactor coolant to flow downwardly internally of the shrouds over the tube bundle and exit through the lower end of the inner shroud for passage to the return duct in the reactor vessel.

  6. Process Heat Exchanger Options for the Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-06-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  7. Process Heat Exchanger Options for Fluoride Salt High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-04-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  8. Acoustically enhanced heat exchange and drying apparatus

    DOE Patents [OSTI]

    Bramlette, T. Tazwell (Livermore, CA); Keller, Jay O. (Oakland, CA)

    1989-01-01

    A heat transfer apparatus includes a first chamber having a first heat transfer gas inlet, a second heat transfer gas inlet, and an outlet. A first heat transfer gas source provides a first gas flow to the first chamber through the first heat transfer gas inlet. A second gas flow through a second chamber connected to the side of the first chamber, generates acoustic waves which bring about acoustical coupling of the first and second gases in the acoustically augmented first chamber. The first chamber may also include a material inlet for receiving material to be dried, in which case the gas outlet serves as a dried material and gas outlet.

  9. Oscillating side-branch enhancements of thermoacoustic heat exchangers

    DOE Patents [OSTI]

    Swift, Gregory W.

    2003-05-13

    A regenerator-based engine or refrigerator has a regenerator with two ends at two different temperatures, through which a gas oscillates at a first oscillating volumetric flow rate in the direction between the two ends and in which the pressure of the gas oscillates, and first and second heat exchangers, each of which is at one of the two different temperatures. A dead-end side branch into which the gas oscillates has compliance and is connected adjacent to one of the ends of the regenerator to form a second oscillating gas flow rate additive with the first oscillating volumetric flow rate, the compliance having a volume effective to provide a selected total oscillating gas volumetric flow rate through the first heat exchanger. This configuration enables the first heat exchanger to be configured and located to better enhance the performance of the heat exchanger rather than being confined to the location and configuration of the regenerator.

  10. A fundamentally new approach to air-cooled heat exchangers.

    SciTech Connect (OSTI)

    Koplow, Jeffrey P.

    2010-01-01

    We describe breakthrough results obtained in a feasibility study of a fundamentally new architecture for air-cooled heat exchangers. A longstanding but largely unrealized opportunity in energy efficiency concerns the performance of air-cooled heat exchangers used in air conditioners, heat pumps, and refrigeration equipment. In the case of residential air conditioners, for example, the typical performance of the air cooled heat exchangers used for condensers and evaporators is at best marginal from the standpoint the of achieving maximum the possible coefficient of performance (COP). If by some means it were possible to reduce the thermal resistance of these heat exchangers to a negligible level, a typical energy savings of order 30% could be immediately realized. It has long been known that a several-fold increase in heat exchanger size, in conjunction with the use of much higher volumetric flow rates, provides a straight-forward path to this goal but is not practical from the standpoint of real world applications. The tension in the market place between the need for energy efficiency and logistical considerations such as equipment size, cost and operating noise has resulted in a compromise that is far from ideal. This is the reason that a typical residential air conditioner exhibits significant sensitivity to reductions in fan speed and/or fouling of the heat exchanger surface. The prevailing wisdom is that little can be done to improve this situation; the 'fan-plus-finned-heat-sink' heat exchanger architecture used throughout the energy sector represents an extremely mature technology for which there is little opportunity for further optimization. But the fact remains that conventional fan-plus-finned-heat-sink technology simply doesn't work that well. Their primary physical limitation to performance (i.e. low thermal resistance) is the boundary layer of motionless air that adheres to and envelops all surfaces of the heat exchanger. Within this boundary layer

  11. Brazed aluminum, Plate-fin heat exchangers for OTEC

    SciTech Connect (OSTI)

    Foust, H.D.

    1980-12-01

    Brazed aluminum plate-fin heat exchangers have been available for special applications for over thirty years. The performance, compactness, versatility, and low cost of these heat exchangers has been unequaled by other heat exchanger configuration. The application of brazed aluminum has been highly limited because of necessary restrictions for clean non-corrosive atmospheres. Air and gas separation have provided ideal conditions for accepting brazed aluminum and in turn have benefited by the salient features of these plate-fin heat exchangers. In fact, brazed aluminum and cryogenic gas and air separation have become nearly synonymous. Brazed aluminum in its historic form could not be considered for a seawater atmosphere. However, technology presents a new look of significant importance to OTEC in terms of compactness and cost. The significant technological variation made was to include one-piece hollow extensions for the seawater passages. Crevice corrosion sites are thereby entirely eliminated and pitting corrosion attack will be controlled by an integral and sacrificial layer of a zinc-aluminum alloy. This paper on brazed aluminum plate-fin heat exchangers for OTEC will aquaint the reader with the state-of-art and variations suggested to qualify this form of aluminum for seawater use. In order to verify the desirable cost potential for OTEC, Trane teamed with Westinghouse to perform an OTEC system analysis with this heat exchanger. These results are very promising and reported in detail elsewhere.

  12. Design issues of a thermoacoustic refrigerator and its heat exchangers

    SciTech Connect (OSTI)

    Wetzel, M.; Herman, C.

    1996-12-31

    Thermoacoustic refrigeration is a fast advancing new refrigeration technology. Performance calculations indicate remarkable values for the thermoacoustic core of a thermoacoustic refrigerator. The thermoacoustic core is responsible for pumping heat from a cold to a hot temperature reservoir. However, the systems necessary to support the thermoacoustic core, such as heat exchangers and acoustic drivers are the weak points of this refrigeration technology. Particularly, heat exchangers were designed so far without any optimization. A reason for this is the lack of knowledge of the flow structures and heat transfer phenomena at the interface between the thermoacoustic core and the heat exchangers. For the purpose of gaining better insight, the authors built a thermoacoustic refrigerator model and applied visualization techniques, such as smoke injection and holographic interferometry, to visualize the flow and temperature fields at the interface.

  13. Sabdia's Radial Flow Air Bearing Heat Exchanger

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Sandia Cooler) vapor chamber hydrodynamic air bearing heat-sink-impeller Dr. Jeff Koplow, jkoplow@sandia.gov Sandia National Laboratories Project Summary Timeline: Start date: ...

  14. Fast reactor power plant design having heat pipe heat exchanger

    DOE Patents [OSTI]

    Huebotter, P.R.; McLennan, G.A.

    1984-08-30

    The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

  15. Fast reactor power plant design having heat pipe heat exchanger

    DOE Patents [OSTI]

    Huebotter, Paul R.; McLennan, George A.

    1985-01-01

    The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

  16. Self-defrosting recuperative air-to-air heat exchanger

    DOE Patents [OSTI]

    Drake, R.L.

    1993-12-28

    A heat exchanger is described which includes a stationary spirally or concentrically wound heat exchanger core with rotating baffles on upper and lower ends thereof. The rotating baffles include rotating inlets and outlets which are in communication with respective fixed inlets and outlets via annuli. The rotation of the baffles causes a concurrent rotation of the temperature distribution within the stationary exchanger core, thereby preventing frost build-up in some applications and preventing the formation of hot spots in other applications. 3 figures.

  17. Temperature control system for a J-module heat exchanger

    DOE Patents [OSTI]

    Basdekas, Demetrios L.; Macrae, George; Walsh, Joseph M.

    1978-01-01

    The level of primary fluid is controlled to change the effective heat transfer area of a heat exchanger utilized in a liquid metal nuclear power plant to eliminate the need for liquid metal control valves to regulate the flow of primary fluid and the temperature of the effluent secondary fluid.

  18. Renormalized anisotropic exchange for representing heat assisted magnetic recording media

    SciTech Connect (OSTI)

    Jiao, Yipeng; Liu, Zengyuan; Victora, R. H.

    2015-05-07

    Anisotropic exchange has been incorporated in a description of magnetic recording media near the Curie temperature, as would be found during heat assisted magnetic recording. The new parameters were found using a cost function that minimized the difference between atomistic properties and those of renormalized spin blocks. Interestingly, the anisotropic exchange description at 1.5 nm discretization yields very similar switching and magnetization behavior to that found at 1.2 nm (and below) discretization for the previous isotropic exchange. This suggests that the increased accuracy of anisotropic exchange may also reduce the computational cost during simulation.

  19. Advanced Rotating Heat Exchangers | Department of Energy

    Energy Savers [EERE]

    2006 (Westphalen, D., Roth, K. W. and Brodrick,J. (2006) 'Heat transfer enhancement', ASHRAE Journal,48(4), 68-71.) Contacts DOE Technology Manager: Tony Bouza Performer: Omar ...

  20. Advanced Rotating Heat Exchangers | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    D., Roth, K. W. and Brodrick,J. (2006) 'Heat transfer enhancement', ASHRAE Journal,48(4), 68-71.) Contacts DOE Technology Manager: Tony Bouza Performer: Ed Vineyard,...

  1. Direct-contact closed-loop heat exchanger

    DOE Patents [OSTI]

    Berry, G.F.; Minkov, V.; Petrick, M.

    1981-11-02

    A high temperature heat exchanger is disclosed which has a closed loop and a heat transfer liquid within the loop, the closed loop having a first horizontal channel with inlet and outlet means for providing direct contact of a first fluid at a first temperature with the heat transfer liquid, a second horizontal channel with inlet and outlet means for providing direct contact of a second fluid at a second temperature with the heat transfer liquid, and means for circulating the heat transfer liquid.

  2. Carbon Nanotube Heat-Exchange Systems - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen and Fuel Cell Hydrogen and Fuel Cell Advanced Materials Advanced Materials Find More Like This Return to Search Carbon Nanotube Heat-Exchange Systems National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary Most power-generation systems produce heat as a by-product. For example, internal combustion engines used to power most vehicles today combust a high-energy fuel (e.g., gasoline) to generate mechanical motion and heat. Fuel cells that

  3. Special heat transfer monitor (HTM) for the Trane Company OTEC heat exchanger

    SciTech Connect (OSTI)

    Kuzay, T.M.; Panchal, C.B.; Gavin, A.P.

    1981-02-01

    A Heat Transfer Monitor (HTM) is a sensitive device which quantifies development of biofouling in the OTEC heat exchanger surfaces in terms of degrading heat transfer coefficient as biofouling progresses. The Carnegie-Mellon University (CMU) type HTM has been successfully utilized to date for plain circular OTEC heat exchanger tubes. With the development of compact heat exchangers for OTEC with non-circular and/or complex tube geometries, a device independent HTM (Universal Monitor) concept is being sought. For the meantime, however, novel methods have been developed to extend the principles of the CMU type HTM to noncircular tube geometries. The theory, formulation, analytical solutions and laboratory test results are presented for the novel use of the CMU HTM concept with such a special tube for the Trane Company heat exchanger for OTEC.

  4. Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump

    DOE Patents [OSTI]

    Phillips, Benjamin A.; Zawacki, Thomas S.

    1996-12-03

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use the working solution of the absorption system for the heat transfer medium. A combination of weak and rich liquor working solution is used as the heat transfer medium.

  5. Progress Report for Diffusion Welding of the NGNP Process Application Heat Exchangers

    SciTech Connect (OSTI)

    R.E. Mizia; D.E. Clark; M.V. Glazoff; T.E. Lister; T.L. Trowbridge

    2011-04-01

    The NGNP Project is currently investigating the use of metallic, diffusion welded, compact heat exchangers to transfer heat from the primary (reactor side) heat transport system to the secondary heat transport system. The intermediate heat exchanger will transfer this heat to downstream applications such as hydrogen production, process heat, and electricity generation. The channeled plates that make up the heat transfer surfaces of the intermediate heat exchanger will have to be assembled into an array by diffusion welding.

  6. Heat exchanger module for stirling engines

    SciTech Connect (OSTI)

    Darche, M. J. P.; Carlquist, S.

    1985-02-12

    The invention relates to Stirling engines and provides a modular assembly composed of a cylinder head, a heater, a regenerator, a cooler and a cold duct, and making it possible by mounting a plurality of identical modules on an engine assembly to construct a multi-cylinder double acting Stirling engine of the indirect heating type.

  7. Liquid Salt Heat Exchanger Technology for VHTR Based Applications

    SciTech Connect (OSTI)

    Anderson, Mark; Sridhara, Kumar; Allen, Todd; Peterson, Per

    2012-10-11

    The objective of this research is to evaluate performance of liquid salt fluids for use as a heat carrier for transferring high-temperature process heat from the very high-temperature reactor (VHTR) to chemical process plants. Currently, helium is being considered as the heat transfer fluid; however, the tube size requirements and the power associated with pumping helium may not be economical. Recent work on liquid salts has shown tremendous potential to transport high-temperature heat efficiently at low pressures over long distances. This project has two broad objectives: To investigate the compatibility of Incoloy 617 and coated and uncoated SiC ceramic composite with MgCl2-KCl molten salt to determine component lifetimes and aid in the design of heat exchangers and piping; and, To conduct the necessary research on the development of metallic and ceramic heat exchangers, which are needed for both the helium-to-salt side and salt-to-process side, with the goal of making these heat exchangers technologically viable. The research will consist of three separate tasks. The first task deals with material compatibility issues with liquid salt and the development of techniques for on-line measurement of corrosion products, which can be used to measure material loss in heat exchangers. Researchers will examine static corrosion of candidate materials in specific high-temperature heat transfer salt systems and develop an in situ electrochemical probe to measure metallic species concentrations dissolved in the liquid salt. The second task deals with the design of both the intermediate and process side heat exchanger systems. Researchers will optimize heat exchanger design and study issues related to corrosion, fabrication, and thermal stresses using commercial and in-house codes. The third task focuses integral testing of flowing liquid salts in a heat transfer/materials loop to determine potential issues of using the salts and to capture realistic behavior of the salts in a

  8. Experimental investigation of a reticulated porous alumina heat exchanger for high temperature gas heat recovery

    SciTech Connect (OSTI)

    Banerjee, A; Chandran, RB; Davidson, JH

    2015-01-22

    The present study presents an experimental study of a prototype counter-flow heat exchanger designed to recover sensible heat from inert and reactive gases flowing through a high temperature solar reactor for splitting CO2. The tube-in-tube heat exchanger is comprised of two concentric alumina tubes, each filled with reticulated porous alumina with a nominal porosity of 80% and pore density of 5 pores per inch (ppi). The RPC provides high heat transfer surface area per unit volume (917 m(-1)) with low pressure drop. Measurements include the permeability, inertial coefficient, overall heat transfer coefficient, effectiveness and pressure drop. For laminar flow and an inlet gas temperature of 1240 K, the overall heat transfer coefficients are 36-41 W m(-2) K-1. The measured performance is in good agreement with a prior CFD model of the heat exchanger. (C) 2014 Elsevier Ltd. All rights reserved.

  9. Materials, Turbomachinery and Heat Exchangers for Supercritical CO2 Systems

    SciTech Connect (OSTI)

    Anderson, Mark; Nellis, Greg; Corradini, Michael

    2012-10-19

    The objective of this project is to produce the necessary data to evaluate the performance of the supercritical carbon dioxide cycle. The activities include a study of materials compatibility of various alloys at high temperatures, the heat transfer and pressure drop in compact heat exchanger units, and turbomachinery issues, primarily leakage rates through dynamic seals. This experimental work will serve as a test bed for model development and design calculations, and will help define further tests necessary to develop high-efficiency power conversion cycles for use on a variety of reactor designs, including the sodium fast reactor (SFR) and very high-temperature gas reactor (VHTR). The research will be broken into three separate tasks. The first task deals with the analysis of materials related to the high-temperature S-CO{sub 2} Brayton cycle. The most taxing materials issues with regard to the cycle are associated with the high temperatures in the reactor side heat exchanger and in the high-temperature turbine. The system could experience pressures as high as 20MPa and temperatures as high as 650°C. The second task deals with optimization of the heat exchangers required by the S-CO{sub 2} cycle; the S-CO{sub 2} flow passages in these heat exchangers are required whether the cycle is coupled with a VHTR or an SFR. At least three heat exchangers will be required: the pre-cooler before compression, the recuperator, and the heat exchanger that interfaces with the reactor coolant. Each of these heat exchangers is unique and must be optimized separately. The most challenging heat exchanger is likely the pre-cooler, as there is only about a 40°C temperature change but it operates close to the CO{sub 2} critical point, therefore inducing substantial changes in properties. The proposed research will focus on this most challenging component. The third task examines seal leakage through various dynamic seal designs under the conditions expected in the S-CO{sub 2} cycle

  10. Diffusion Welding of Compact Heat Exchangers for Nuclear Applications

    SciTech Connect (OSTI)

    Denis Clark; Ron Mizia; Dr. Michael V. Glazoff; Mr. Michael W. Patterson

    2012-06-01

    The next-­-generation nuclear plant (NGNP) is designed to be a flexible source of energy, producing various mixes of electrical energy and process heat (for example, for hydrogen generation) on demand. Compact heat exchangers provide an attractive way to move energy from the helium primary reactor coolant to process heat uses. For process heat efficiency, reactor outlet temperatures of 750-­-900°C are desirable. There are minor but deleterious components in the primary coolant; the number of alloys that can handle this environment is small. The present work concentrates on Alloys 800H and 617.

  11. Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy SBIR Phase 2B) Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Building-Integrated Heat & Moisture Exchange (SBIR Phase 2B) Lead Performer: Architectural Applications - Portland, Oregon Partner: Oregon State University - Corvallis, Oregon DOE Funding: $1,009,999 Cost

  12. Supercritical Carbon Dioxide Turbo-Expander and Heat Exchangers

    Broader source: Energy.gov [DOE]

    This fact sheet describes a supercritical carbon dioxide turbo-expander and heat exchangers project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by the Southwest Research Institute, is working to develop a megawatt-scale s-CO2 hot-gas turbo-expander optimized for the highly transient solar power plant profile. The team is also working to optimize novel printed circuit heat exchangers for s-CO2 applications to drastically reduce their manufacturing costs.

  13. Internal dust recirculation system for a fluidized bed heat exchanger

    DOE Patents [OSTI]

    Gamble, Robert L.; Garcia-Mallol, Juan A.

    1981-01-01

    A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided in a heat exchange relation to the bed and includes a steam drum disposed adjacent the bed and a tube bank extending between the steam drum and a water drum. The tube bank is located in the path of the effluent gases exiting from the bed and a baffle system is provided to separate the solid particulate matter from the effluent gases. The particulate matter is collected and injected back into the fluidized bed.

  14. Heat exchanger selection and design analyses for metal hydride heat pump systems

    SciTech Connect (OSTI)

    Mazzucco, Andrea; Voskuilen, Tyler G.; Waters, Essene L.; Pourpoint, Timothee L.; Rokni, Masoud

    2016-01-01

    This paper presents a design analysis for the development of highly efficient heat exchangers within stationary metal hydride heat pumps. The design constraints and selected performance criteria are applied to three representative heat exchangers. The proposed thermal model can be applied to select the most efficient heat exchanger design and provides outcomes generally valid in a pre-design stage. Heat transfer effectiveness is the principal performance parameter guiding the selection analysis, the results of which appear to be mildly (up to 13%) affected by the specific Nusselt correlation used. The thermo-physical properties of the heat transfer medium and geometrical parameters are varied in the sensitivity analysis, suggesting that the length of independent tubes is the physical parameter that influences the performance of the heat exchangers the most. The practical operative regions for each heat exchanger are identified by finding the conditions over which the heat removal from the solid bed enables a complete and continuous hydriding reaction. The most efficient solution is a design example that achieves the target effectiveness of 95%.

  15. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    SciTech Connect (OSTI)

    Mittereder, N.; Poerschke, A.

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season. Upon completion of the monitoring phase, measurements revealed that the initial TRNSYS simulated horizontal sub-slab ground loop heat exchanger fluid temperatures and heat transfer rates differed from the measured values. To determine the cause of this discrepancy, an updated model was developed utilizing a new TRNSYS subroutine for simulating sub-slab heat exchangers. Measurements of fluid temperature, soil temperature, and heat transfer were used to validate the updated model.

  16. Heat exchanger selection and design analyses for metal hydride heat pump systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mazzucco, Andrea; Voskuilen, Tyler G.; Waters, Essene L.; Pourpoint, Timothee L.; Rokni, Masoud

    2016-01-01

    This paper presents a design analysis for the development of highly efficient heat exchangers within stationary metal hydride heat pumps. The design constraints and selected performance criteria are applied to three representative heat exchangers. The proposed thermal model can be applied to select the most efficient heat exchanger design and provides outcomes generally valid in a pre-design stage. Heat transfer effectiveness is the principal performance parameter guiding the selection analysis, the results of which appear to be mildly (up to 13%) affected by the specific Nusselt correlation used. The thermo-physical properties of the heat transfer medium and geometrical parameters aremore » varied in the sensitivity analysis, suggesting that the length of independent tubes is the physical parameter that influences the performance of the heat exchangers the most. The practical operative regions for each heat exchanger are identified by finding the conditions over which the heat removal from the solid bed enables a complete and continuous hydriding reaction. The most efficient solution is a design example that achieves the target effectiveness of 95%.« less

  17. ASME code considerations for the compact heat exchanger

    SciTech Connect (OSTI)

    Nestell, James; Sham, Sam

    2015-08-31

    The mission of the U.S. Department of Energy (DOE), Office of Nuclear Energy is to advance nuclear power in order to meet the nation's energy, environmental, and energy security needs. Advanced high temperature reactor systems such as sodium fast reactors and high and very high temperature gas-cooled reactors are being considered for the next generation of nuclear reactor plant designs. The coolants for these high temperature reactor systems include liquid sodium and helium gas. Supercritical carbon dioxide (sCO₂), a fluid at a temperature and pressure above the supercritical point of CO₂, is currently being investigated by DOE as a working fluid for a nuclear or fossil-heated recompression closed Brayton cycle energy conversion system that operates at 550°C (1022°F) at 200 bar (2900 psi). Higher operating temperatures are envisioned in future developments. All of these design concepts require a highly effective heat exchanger that transfers heat from the nuclear or chemical reactor to the chemical process fluid or the to the power cycle. In the nuclear designs described above, heat is transferred from the primary to the secondary loop via an intermediate heat exchanger (IHX) and then from the intermediate loop to either a working process or a power cycle via a secondary heat exchanger (SHX). The IHX is a component in the primary coolant loop which will be classified as "safety related." The intermediate loop will likely be classified as "not safety related but important to safety." These safety classifications have a direct bearing on heat exchanger design approaches for the IHX and SHX. The very high temperatures being considered for the VHTR will require the use of very high temperature alloys for the IHX and SHX. Material cost considerations alone will dictate that the IHX and SHX be highly effective; that is, provide high heat transfer area in a small volume. This feature must be accompanied by low pressure drop and mechanical reliability and robustness

  18. Testing of thermally enhanced cement ground heat exchanger grouts

    SciTech Connect (OSTI)

    Kavanaugh, S.P.; Allan, M.L.

    1999-07-01

    Optimal performance of closed-loop, ground-source heat pumps (ground-coupled heat pumps) is dependent upon the thermal properties of the backfill in the annual region between the ground heat exchanger (GHEX) tubes and the outer bore wall. Equally important is the protection of groundwater aquifers from contaminants that may flow from the surface of other aquifers through poorly sealed boreholes. Conventional cement and bentonite-based grouts have relatively low thermal conductivities. Loop requirements often increase beyond the allotted budget in applications where regulatory bodies require the entire heat exchanger length to be grouted. This paper reports on the results of four mixes of thermally enhanced cementitious grouts. Four grouts were evaluated in a test stand to minimize the impact of external factors typically present in field tests. The test stand accepts up to 6 in. (15 cm) ground heat exchangers in a 10 ft (3 m) test section. Controlled testing is performed in either the cooling mode (loop above 85 F [29 C]) or heating mode (loop at 32 F [0 C]), and the temperature of the outer bore wall is held constant with a groundwater source. Results indicate cement grouts that are enhanced with low-cost additives have thermal conductivities three to four times as large as conventional high-solids bentonite grouts. This would result in reduced heat exchanger lengths compared to those grouted with bentonite. There appears to be no measurable increase in overall borehole resistance due to separation of the colder tubes from the grout in the heating mode. This discussion does not include pumpability, permeability, and material handling issues, which must be thoroughly investigated before any grout can be recommended for use.

  19. Metallic heat exchangers for coal gasification

    SciTech Connect (OSTI)

    Natesan, K.

    1984-07-01

    A high-temperature corrosion program is being conducted to evaluate the corrosion behavior of selected metallic alloys and coatings in mixed-gas atmospheres for application in heat recovery systems of coal gasification schemes. The experiments conducted with internally air-cooled specimens have established three key variables, namely the gas temperature, metal temperature, and gas chemistry. In addition, the alloy chemistry and exposure time have a strong influence on the corrosion scale morphologies and metal recession rates. The results showed that the scale growth in carbon steel and low- to medium-chromium steels is predominantly linear with time. Selection of these materials will be primarily based upon acceptable corrosion wastage rate. On the other hand, high-chromium alloys can develop thin oxide scales resulting in negligible wastage via corrosion, but are susceptible to accelerated corrosion in mixed-gas atmospheres. 6 references, 12 figures, 4 tables.

  20. Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump

    DOE Patents [OSTI]

    Phillips, B.A.; Zawacki, T.S.

    1998-07-21

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use, as the heat transfer medium, the working fluid of the absorption system taken from the generator at a location where the working fluid has a rich liquor concentration. 5 figs.

  1. Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump

    DOE Patents [OSTI]

    Phillips, Benjamin A.; Zawacki, Thomas S.

    1998-07-21

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use, as the heat transfer medium, the working fluid of the absorption system taken from the generator at a location where the working fluid has a rich liquor concentration.

  2. Heat exchanger with intermediate evaporating and condensing fluid

    DOE Patents [OSTI]

    Fraas, Arthur P.

    1978-01-01

    A shell and tube-type heat exchanger, such as a liquid sodium-operated steam generator for use in nuclear reactors, comprises a shell containing a primary fluid tube bundle, a secondary fluid tube bundle at higher elevation, and an intermediate fluid vaporizing at the surface of the primary fluid tubes and condensing at the surface of the secondary fluid tubes.

  3. Heat exchanger with leak detecting double wall tubes

    DOE Patents [OSTI]

    Bieberbach, George; Bongaards, Donald J.; Lohmeier, Alfred; Duke, James M.

    1981-01-01

    A straight shell and tube heat exchanger utilizing double wall tubes and three tubesheets to ensure separation of the primary and secondary fluid and reliable leak detection of a leak in either the primary or the secondary fluids to further ensure that there is no mixing of the two fluids.

  4. Fouling characteristics of compact heat exchangers and enhanced tubes.

    SciTech Connect (OSTI)

    Panchal, C. B.; Rabas, T. J.

    1999-07-15

    Fouling is a complex phenomenon that (1) encompasses formation and transportation of precursors, and (2) attachment and possible removal of foulants. A basic understanding of fouling mechanisms should guide the development of effective mitigation techniques. The literature on fouling in complex flow passages of compact heat exchangers is limited; however, significant progress has been made with enhanced tubes.

  5. Integral collector storage system with heat exchange apparatus

    DOE Patents [OSTI]

    Rhodes, Richard O.

    2004-04-20

    The present invention relates to an integral solar energy collector storage systems. Generally, an integral collector storage system includes a tank system, a plurality of heat exchange tubes with at least some of the heat exchange tubes arranged within the tank system, a first glazing layer positioned over the tank system and a base plate positioned under the tank system. In one aspect of the invention, the tank system, the first glazing layer an the base plate each include protrusions and a clip is provided to hold the layers together. In another aspect of the invention, the first glazing layer and the base plate are ribbed to provide structural support. This arrangement is particularly useful when these components are formed from plastic. In yet another aspect of the invention, the tank system has a plurality of interconnected tank chambers formed from tubes. In this aspect, a supply header pipe and a fluid return header pipe are provided at a first end of the tank system. The heat exchange tubes have inlets coupled to the supply header pipe and outlets coupled to the return header pipe. With this arrangement, the heat exchange tubes may be inserted into the tank chambers from the first end of the tank system.

  6. Finned Tube With Vortex Generators For A Heat Exchanger.

    DOE Patents [OSTI]

    Sohal, Manohar S.; O'Brien, James E.

    2005-12-20

    A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

  7. Finned Tube With Vortex Generators For A Heat Exchanger.

    DOE Patents [OSTI]

    Sohal, Monohar S.; O'Brien, James E.

    2004-09-14

    A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at least one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

  8. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    SciTech Connect (OSTI)

    Mittereder, Nick; Poerschke, Andrew

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season.

  9. Secondary heat exchanger design and comparison for advanced high temperature reactor

    SciTech Connect (OSTI)

    Sabharwall, P.; Kim, E. S.; Siahpush, A.; McKellar, M.; Patterson, M.

    2012-07-01

    Next generation nuclear reactors such as the advanced high temperature reactor (AHTR) are designed to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. This study considers two different types of heat exchangers - helical coiled heat exchanger and printed circuit heat exchanger - as possible options for the AHTR secondary heat exchangers with distributed load analysis and comparison. Comparison is provided for all different cases along with challenges and recommendations. (authors)

  10. Novel Power Electronics Three-Dimensional Heat Exchanger: Preprint

    SciTech Connect (OSTI)

    Bennion, K.; Cousineau, J.; Lustbader, J.; Narumanchi, S.

    2014-08-01

    Electric drive systems for vehicle propulsion enable technologies critical to meeting challenges for energy, environmental, and economic security. Enabling cost-effective electric drive systems requires reductions in inverter power semiconductor area. As critical components of the electric drive system are made smaller, heat removal becomes an increasing challenge. In this paper, we demonstrate an integrated approach to the design of thermal management systems for power semiconductors that matches the passive thermal resistance of the packaging with the active convective cooling performance of the heat exchanger. The heat exchanger concept builds on existing semiconductor thermal management improvements described in literature and patents, which include improved bonded interface materials, direct cooling of the semiconductor packages, and double-sided cooling. The key difference in the described concept is the achievement of high heat transfer performance with less aggressive cooling techniques by optimizing the passive and active heat transfer paths. An extruded aluminum design was selected because of its lower tooling cost, higher performance, and scalability in comparison to cast aluminum. Results demonstrated a heat flux improvement of a factor of two, and a package heat density improvement over 30%, which achieved the thermal performance targets.

  11. Heat exchanger efficiently operable alternatively as evaporator or condenser

    DOE Patents [OSTI]

    Ecker, Amir L.

    1981-01-01

    A heat exchanger adapted for efficient operation alternatively as evaporator or condenser and characterized by flexible outer tube having a plurality of inner conduits and check valves sealingly disposed within the outer tube and connected with respective inlet and outlet master flow conduits and configured so as to define a parallel flow path for a first fluid such as a refrigerant when flowed in one direction and to define a serpentine and series flow path for the first fluid when flowed in the opposite direction. The flexible outer tube has a heat exchange fluid, such as water, flowed therethrough by way of suitable inlet and outlet connections. The inner conduits and check valves form a package that is twistable so as to define a spiral annular flow path within the flexible outer tube for the heat exchange fluid. The inner conduits have thin walls of highly efficient heat transfer material for transferring heat between the first and second fluids. Also disclosed are specific materials and configurations.

  12. Light weight and economical exhaust heat exchanger for waste heat recovery using mixed radiant and convective heat transfer

    Broader source: Energy.gov [DOE]

    A hybrid heat exchanger is designed to keep highly stressed materials around the working fluid at a moderate temperature so that it can operate at higher working fluid pressure.

  13. Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation

    SciTech Connect (OSTI)

    Xing, Lu; Cullin, James; Spitler, Jeffery; Im, Piljae; Fisher, Daniel

    2011-01-01

    A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

  14. Heat exchanger sizing for vertical closed-loop ground-source heat pumps

    SciTech Connect (OSTI)

    Cane, R.L.D.; Clemes, S.B.; Morrison, A.; Hughes, P.J.

    1995-12-31

    A building energy simulation program has been used in conjunction with a ground heat exchanger sizing algorithm to develop general guidelines on how to size vertical ground heat exchangers for closed-loop ground-source heat pump systems in large buildings. The analysis considered three commercial building types of varying size with different internal loads and heat pump efficiencies. Each building variation was simulated in seven cities, three in the US and four in Canada. The ground heat exchanger sizing algorithm has been previously validated against actual system data. The analysis results showed a strong correlation between heat exchanger length required and annual energy rejected to the ground, if the building was cooling-dominated, or annual energy extracted from the ground, if the building was heating-dominated. The resulting sizing guidelines recommend hour-by-hour energy analysis to determine the energy extracted from and rejected to the building water loop. Using this information the designer will have available easy-to-use, accurate sizing guidelines that should result in more economical installations than those based on previous ``rule of thumb`` guidelines.

  15. Performance of dehumidifying heat exchangers with and without wetting coatings

    SciTech Connect (OSTI)

    Hong, K.; Webb, R.L.

    1999-11-01

    Limited previous work has shown that use of special hydrophilic coatings will provide lower air pressure drop in finned tube heat exchangers operated under dehumidifying conditions. However, no detailed work has been reported on the effect of different coating types, or different fin surface geometries on the wet pressure drop. In this study, wind tunnel tests were performed on three different fin geometries (wavy, lanced, and louver) under wet and dry conditions. All dehumidification tests were done for fully wet surface conditions. For each geometry, the tests were performed on uncoated and coated heat exchangers. For all three fin geometries, the wet-to-dry pressure drop ratio was 1.2 at 2.5 m/s frontal air velocity. The coatings have no influence on the wet or dry heat transfer coefficient. However, the wet surface heat transfer coefficient was 10 to 30% less than the dry heat transfer coefficient, depending on the particular fin geometry. The effect of the fin press oil on wet pressure drop was also studied. If the oil contains a surfactant, good temporary wetting can be obtained on an uncoated surface; however, this effect is quickly degraded as the oil is washed from the surface during wet operation. This work also provides a critical assessment of data reduction methods for wet surface operation, including calculation of the fin efficiency.

  16. Selection, Evaluation, And Rating of Compact Heat exchangers

    Energy Science and Technology Software Center (OSTI)

    2014-10-07

    SEARCH determines and optimizes the design of a compact heat exchanger for specified process conditions. The user specifies process boundary conditions including the fluid state and flow rate and SEARCH will determine the optimum flow arrangement, channel geometry, and mechanical design for the unit. Fluids are modeled using NUST Refprop or tabulated values. A variety of thermal-hydraulic correlations are available including user-defined equations to accurately capture the heat transfer and pressure drop behavior of themore » process flows.« less

  17. Building America Technology Solutions for New and Existing Homes: Foundation Heat Exchanger, Oak Ridge, Tennessee

    Broader source: Energy.gov [DOE]

    This case study introduces the foundation heat exchanger that can significantly reduce the cost of the ground source heat pump (GHSP).

  18. Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange

    SciTech Connect (OSTI)

    McBride, Troy O.; Bell, Alexander; Bollinger, Benjamin R.

    2012-08-07

    In various embodiments, efficiency of energy storage and recovery systems compressing and expanding gas is improved via heat exchange between the gas and a heat-transfer fluid.

  19. Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange

    DOE Patents [OSTI]

    McBride, Troy O; Bell, Alexander; Bollinger, Benjamin R; Shang, Andrew; Chmiel, David; Richter, Horst; Magari, Patrick; Cameron, Benjamin

    2013-07-02

    In various embodiments, efficiency of energy storage and recovery systems compressing and expanding gas is improved via heat exchange between the gas and a heat-transfer fluid.

  20. Integrated Three-Dimensional Module Heat Exchange for Power Electronics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cooling - Energy Innovation Portal Vehicles and Fuels Vehicles and Fuels Find More Like This Return to Search Integrated Three-Dimensional Module Heat Exchange for Power Electronics Cooling National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary The power electronics market has started to grow dramatically with the onset of new technologies in automotive applications, power generation, energy storage, and other growing markets. A critical element

  1. Fouling of HVAC fin and tube heat exchangers

    SciTech Connect (OSTI)

    Siegel, Jeffrey; Carey, Van P.

    2001-07-01

    Fin and tube heat exchangers are used widely in residential, commercial and industrial HVAC applications. Invariably, indoor and outdoor air contaminants foul these heat exchangers. This fouling can cause decreased capacity and efficiency of the HVAC equipment as well as indoor air quality problems related to microbiological growth. This paper describes laboratory studies to investigate the mechanisms that cause fouling. The laboratory experiments involve subjecting a 4.7 fins/cm (12 fins/inch) fin and tube heat exchanger to an air stream that contains monodisperse particles. Air velocities ranging from 1.5-5.2 m/s (295 ft/min-1024 ft/min) and particle sizes from 1--8.6 {micro}m are used. The measured fraction of particles that deposit as well as information about the location of the deposited material indicate that particles greater than about 1 {micro}m contribute to fouling. These experimental results are used to validate a scaling analysis that describes the relative importance of several deposition mechanisms including impaction, Brownian diffusion, turbophoresis, thermophoresis, diffusiophoresis, and gravitational settling. The analysis is extended to apply to different fin spacings and particle sizes typical of those found in indoor air.

  2. Heat exchanger bypass system for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A heat exchanger bypass system for an absorption refrigeration system is disclosed. The bypass system operates to pass strong solution from the generator around the heat exchanger to the absorber of the absorption refrigeration system when strong solution builds up in the generator above a selected level indicative of solidification of strong solution in the heat exchanger or other such blockage. The bypass system includes a bypass line with a gooseneck located in the generator for controlling flow of strong solution into the bypass line and for preventing refrigerant vapor in the generator from entering the bypass line during normal operation of the refrigeration system. Also, the bypass line includes a trap section filled with liquid for providing a barrier to maintain the normal pressure difference between the generator and the absorber even when the gooseneck of the bypass line is exposed to refrigerant vapor in the generator. Strong solution, which may accumulate in the trap section of the bypass line, is diluted, to prevent solidification, by supplying weak solution to the trap section from a purge system for the absorption refrigeration system.

  3. Fluidized bed heat exchanger with water cooled air distributor and dust hopper

    DOE Patents [OSTI]

    Jukkola, Walfred W.; Leon, Albert M.; Van Dyk, Jr., Garritt C.; McCoy, Daniel E.; Fisher, Barry L.; Saiers, Timothy L.; Karstetter, Marlin E.

    1981-11-24

    A fluidized bed heat exchanger is provided in which air is passed through a bed of particulate material containing fuel. A steam-water natural circulation system is provided for heat exchange and the housing of the heat exchanger has a water-wall type construction. Vertical in-bed heat exchange tubes are provided and the air distributor is water-cooled. A water-cooled dust hopper is provided in the housing to collect particulates from the combustion gases and separate the combustion zone from a volume within said housing in which convection heat exchange tubes are provided to extract heat from the exiting combustion gases.

  4. Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Ali Siahpush; Michael McKellar; Michael Patterson; Eung Soo Kim

    2012-06-01

    The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers—helical coiled heat exchanger and printed circuit heat exchanger—as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.

  5. Study on the heat transfer of heat exchangers for the Stirling Engine

    SciTech Connect (OSTI)

    Kanzaka, M. ); Iwabuchi, M. )

    1991-01-01

    This paper reports that heat-transfer characteristics in heated tubes under periodically reversing flow conditions have been investigated experimentally using a test apparatus that simulates the heat exchangers for the actual Sterling engine. It was shown that the heat-transfer characteristics under these conditions were greatly affected by the piston phase-angle difference that generates the reversing flow of the working gas, and this phenomenon was proper to the heat transfer under the periodically reversing flow and was different from conventional heat transfer in steady flow. The experimental correlation considering the influence of the piston phase-angle difference for the heat-transfer coefficient has been induced by the use of the working gas velocity evaluated from the Schmidt cycle model which is one of the ideal Sterling cycles.

  6. Countercurrent direct contact heat exchange process and system

    DOE Patents [OSTI]

    Wahl, III, Edward F.; Boucher, Frederic B.

    1979-01-01

    Recovery of energy from geothermal brines and other hot water sources by direct contact heat exchange with a working fluid, such as a hydrocarbon working fluid, e.g. isobutane. The process and system consists of a plurality of stages, each stage including mixing and settling units. In the first stage, hot brine and arm working fluid are intimately mixed and passed into a settler wherein the brine settles to the bottom of the settler and the hot working fluid rises to the top. The hot working fluid is passed to a heat engine or turbine to produce work and the working fluid is then recycled back into the system. The system is comprised of a series of stages each containing a settler and mixer, and wherein the working fluid and the brine flow in a countercurrent manner through the stages to recover the heat from the brine in increments and raise the temperature of the working fluid in increments.

  7. Condensation analysis for plate-frame heat exchangers

    SciTech Connect (OSTI)

    Arman, B.; Rabas, T.J.

    1995-07-01

    A theoretical analysis is presented to predict single component and binary-mixture condensation in plate-frame heat exchangers. A thermodynamic property model based on the Peng-Robinson equation of state was developed for the binary-mixture equilibrium and formulated into a performance prediction program. A set of equations was formulated and a calculation algorithm was developed to predict the local rate of heat and mass transfer for binary mixtures. Friction-factor and heat-transfer-coefficient correlations were developed using experimental data obtained with ammonia condensation. The role of the mass-transfer resistance associated with the condensation process were analyzed for a propane/butane mixture using two limiting cases: (1) no liquid-phase mass-transfer resistance, and (2) infinite liquid-phase mass-transfer resistance. The results show that the vapor-phase mass-transfer resistance is the controlling mechanism for binary-mixture condensation.

  8. Experimental study of mixed convection heat transfer in vertical helically coiled tube heat exchangers

    SciTech Connect (OSTI)

    Ghorbani, N. [School of Mechanical Engineering, University of Leeds, Leeds, England (United Kingdom); Taherian, H. [Department of Engineering Technology and Industrial Distribution, Texas A and M University, College Station, TX (United States); Gorji, M. [Department of Mechanical Engineering, Babol Noushirvani University of Technology, Babol (Iran); Mirgolbabaei, H. [Department of Mechanical Engineering, Islamic Azad University, Jouybar branch, Jouybar (Iran)

    2010-10-15

    In this study the mixed convection heat transfer in a coil-in-shell heat exchanger for various Reynolds numbers, various tube-to-coil diameter ratios and different dimensionless coil pitch was experimentally investigated. The experiments were conducted for both laminar and turbulent flow inside coil. Effects of coil pitch and tube diameters on shell-side heat transfer coefficient of the heat exchanger were studied. Different characteristic lengths were used in various Nusselt number calculations to determine which length best fits the data and several equations were proposed. The particular difference in this study in comparison with the other similar studies was the boundary conditions for the helical coils. The results indicate that the equivalent diameter of shell is the best characteristic length. (author)

  9. Aging management guideline for commercial nuclear power plants - heat exchangers

    SciTech Connect (OSTI)

    Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

    1994-06-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  10. Properties of Alloy 617 for Heat Exchanger Design

    SciTech Connect (OSTI)

    Wright, Richard Neil; Carroll, Laura Jill; Benz, Julian Karl; Wright, Julie Knibloe; Lillo, Thomas Martin; Lybeck, Nancy Jean

    2014-10-01

    Abstract – Alloy 617 is among the primary candidates for very high temperature reactor heat exchangers anticipated for use up to 950ºC. Elevated temperature properties of this alloy and the mechanisms responsible for the observed tensile, creep and creep-fatigue behavior have been characterized over a wide range of test temperatures up to 1000ºC. Properties from the current experimental program have been combined with archival information from previous VHTR research to provide large data sets for many heats of material, product forms, and weldments. The combined data have been analyzed to determine conservative values of yield and tensile strength, strain rate sensitivity, creep-rupture behavior, fatigue and creep- fatigue properties that can be used for engineering design of reactor components. Phenomenological models have been developed to bound the regions over which the engineering properties are well known or can be confidently extrapolated for use in design.

  11. Experimental investigation of plastic finned-tube heat exchangers, with emphasis on material thermal conductivity

    SciTech Connect (OSTI)

    Chen, Lin; Li, Zhen; Guo, Zeng-Yuan

    2009-07-15

    In this paper, two modified types of polypropylene (PP) with high thermal conductivity up to 2.3 W/m K and 16.5 W/m K are used to manufacture the finned-tube heat exchangers, which are prospected to be used in liquid desiccant air conditioning, heat recovery, water source heat pump, sea water desalination, etc. A third plastic heat exchanger is also manufactured with ordinary PP for validation and comparison. Experiments are carried out to determine the thermal performance of the plastic heat exchangers. It is found that the plastic finned-tube heat exchanger with thermal conductivity of 16.5 W/m K can achieve overall heat transfer coefficient of 34 W/m{sup 2} K. The experimental results are compared with calculation and they agree well with each other. Finally, the effect of material thermal conductivity on heat exchanger thermal performance is studied in detail. The results show that there is a threshold value of material thermal conductivity. Below this value improving thermal conductivity can considerably improve the heat exchanger performance while over this value improving thermal conductivity contributes very little to performance enhancement. For the finned-tube heat exchanger designed in this paper, when the plastic thermal conductivity can reach over 15 W/m K, it can achieve more than 95% of the titanium heat exchanger performance and 84% of the aluminum or copper heat exchanger performance with the same dimension. (author)

  12. Integrated heat exchanger design for a cryogenic storage tank

    SciTech Connect (OSTI)

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

    2014-01-29

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

  13. Continuation of Studies on Development of ODS Heat Exchanger Tubing

    SciTech Connect (OSTI)

    Lawrence Brown; David Workman; Bimal Kad; Gaylord Smith; Archie Robertson; Ian Wright

    2008-04-15

    The Department of Energy (DOE), National Energy Technology Center (NETL), has initiated a strategic plan for the development of advanced technologies needed to design and build fossil fuel plants with very high efficiency and environmental performance. These plants, referred to as 'Vision 21' and FutureGen programs by DOE, will produce electricity, chemicals, fuels, or a combination of these products, and possibly secondary products such as steam/heat for industrial use. MA956 is a prime candidate material being considered for a high temperature heat exchanger in the 'Vision 21' and FutureGen programs. This material is an oxide dispersion strengthened (ODS) alloy; however, there are some gaps in the data required to commit to the use of these alloys in a full-size plant. To fill the technology gaps for commercial production and use of the material for 'Advanced Power Generation Systems' this project has performed development activity to significant increase in circumferential strength of MA956 as compared to currently available material, investigated bonding technologies for bonding tube-to-tube joints through joining development, and performed tensile, creep and fire-side corrosion tests to validate the use and fabrication processes of MA956 to heat exchanger tubing applications. Development activities within this projected has demonstrated increased circumferential strength of MA956 tubes through flow form processing. Of the six fabrication technologies for bonding tube-to-tube joints, inertia friction welding (IFW) and flash butt welding (FBW) were identified as processes for joining MA956 tubes. Tensile, creep, and fire-side corrosion test data were generated for both base metal and weld joints. The data can be used for design of future systems employing MA956. Based upon the positive development activities, two test probes were designed and fabricated for field exposure testing at 1204 C ({approx}2200 F) flue gas. The probes contained tube portions with FBW

  14. Optimization of heat exchanger design in a thermoacoustic engine using a second law analysis

    SciTech Connect (OSTI)

    Ishikawa, H.; Hobson, P.A.

    1996-05-01

    An analysis for the time averaged entropy generation due to both flow and heat transfer losses in the heat exchangers of a thermoacoustic engine has been developed. An expression for the optimum dimensionless heat exchanger area corresponding to minimum entropy generation has been determined in terms of three other dimensionless parameters. Optimum heat exchanger areas were calculated for three thermoacoustic devices. For the prime mover components of the thermoacoustic devices investigated where the temperature differences across the regenerator stacks were high, the analysis developed indicated that the heat exchanger at the hot end of the regenerator stack should be smaller than that at the cold end.

  15. Erosion of heat exchanger tubes in fluidized beds

    SciTech Connect (OSTI)

    Johnson, E.K.; Flemmer, R.L.C.

    1991-01-01

    This final report describes the activities of the 3-year project entitled Erosion of Heat Exchanger Tubes In Fluidized Beds.'' which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. [times] 24in. fluidized bed, comparative wear results In a 6in. [times] 6in. fluidized bed, the development of a dragometer and the collection of a comprehensive set of drag force data in the 24in. [times] 24in. bed, Fast Fourier Transform (FFT) analysis of bubble probe data to establish dominant bubble frequencies in the 24in. [times] 24in. bed, the use of a heat flux gauge for measurement of heat transfer coefficients in the 24in. [times] 24in. bed and the modeling of the tube wear in the 24in. [times] 24in. bed. Analysis of the wear data from the 24in. square bed indicates that tube wear increases with increase in superficial velocity, and with increase in tube height. The latter effect is a result of the tubes higher up in the bed seeing greater movement of dense phase than tubes lower down In the bed. In addition, tube wear was found to decrease with increase in particle size, for constant superficial velocity. Three models of tube wear were formulated and provided acceptable prediction of wear when compared with the experimental data.

  16. Analytical Study on Thermal and Mechanical Design of Printed Circuit Heat Exchanger

    SciTech Connect (OSTI)

    Su-Jong Yoon; Piyush Sabharwall; Eung-Soo Kim

    2013-09-01

    The analytical methodologies for the thermal design, mechanical design and cost estimation of printed circuit heat exchanger are presented in this study. In this study, three flow arrangements of parallel flow, countercurrent flow and crossflow are taken into account. For each flow arrangement, the analytical solution of temperature profile of heat exchanger is introduced. The size and cost of printed circuit heat exchangers for advanced small modular reactors, which employ various coolants such as sodium, molten salts, helium, and water, are also presented.

  17. Advanced Heat/Mass Exchanger Technology for Geothermal and solar Renewable

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Systems | Department of Energy Heat/Mass Exchanger Technology for Geothermal and solar Renewable Energy Systems Advanced Heat/Mass Exchanger Technology for Geothermal and solar Renewable Energy Systems Advanced Heat/Mass Exchanger Technology for Geothermal and solar Renewable Energy Systems presentation at the April 2013 peer review meeting held in Denver, Colorado. university_of_nevada_peer2013.pdf (770.58 KB) More Documents & Publications Guide to Developing Air-Cooled Lithium

  18. A self-circulating heat exchanger for use in stirling and

    Office of Scientific and Technical Information (OSTI)

    thermoacoustic-stirling engines (Conference) | SciTech Connect Conference: A self-circulating heat exchanger for use in stirling and thermoacoustic-stirling engines Citation Details In-Document Search Title: A self-circulating heat exchanger for use in stirling and thermoacoustic-stirling engines A major technical hurdle to the implementation of large Stirling engines or thermoacoustic engines is the reliability, performance, and manufacturability of the hot heat exchanger that brings

  19. Technical Information Exchange on Pyrolysis Oil: Potential for a renewable heating oil substitution

    Broader source: Energy.gov [DOE]

    Two-day agenda from the workshop: Technical Information Exchange on Pyrolysis Oil: Potential for a renewable heating oil substitution fuel in New England.

  20. Deposition of biological aerosols on HVAC heat exchangers

    SciTech Connect (OSTI)

    Siegel, Jeffrey; Walker, Ian

    2001-09-01

    Many biologically active materials are transported as bioaerosols 1-10 {micro}m in diameter. These particles can deposit on cooling and heating coils and lead to serious indoor air quality problems. This paper investigates several of the mechanisms that lead to aerosol deposition on fin and tube heat exchangers. A model has been developed that incorporates the effects of several deposition mechanisms, including impaction, Brownian and turbulent diffusion, turbophoresis, thermophoresis, diffusiophoresis, and gravitational settling. The model is applied to a typical range of air velocities that are found in commercial and residential HVAC systems 1 - 6 m/s (200 - 1200 ft/min), particle diameters from 1 - 8 {micro}m, and fin spacings from 3.2 - 7.9 fins/cm (8 - 16 fins/inch or FPI). The results from the model are compared to results from an experimental apparatus that directly measures deposition on a 4.7 fins/cm (12 FPI) coil. The model agrees reasonably well with this measured data and suggests that cooling coils are an important sink for biological aerosols and consequently a potential source of indoor air quality problems.

  1. Low GWP Refrigerants Modelling Study for a Room Air Conditioner Having Microchannel Heat Exchangers

    SciTech Connect (OSTI)

    Shen, Bo; Bhandari, Mahabir S

    2016-01-01

    Microchannel heat exchangers (MHX) have found great successes in residential and commercial air conditioning applications, being compact heat exchangers, to reduce refrigerant charge and material cost. This investigation aims to extend the application of MHXs in split, room air conditioners (RAC), per fundamental heat exchanger and system modelling. For this paper, microchannel condenser and evaporator models were developed, using a segment-to-segment modelling approach. The microchannel heat exchanger models were integrated to a system design model. The system model is able to predict the performance indices, such as cooling capacity, efficiency, sensible heat ratio, etc. Using the calibrated system and heat exchanger models, we evaluated numerous low GWP (global warming potential) refrigerants. The predicted system performance indices, e.g. cooling efficiency, compressor discharge temperature, and required compressor displacement volume etc., are compared. Suitable replacements for R22 and R-410A for the room air conditioner application are recommended.

  2. Feasibility Study of Secondary Heat Exchanger Concepts for the Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall

    2011-09-01

    The work reported herein represents a significant step in the preliminary design of heat exchanger options (material options, thermal design, selection and evaluation methodology with existing challenges). The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production using either a subcritical or supercritical Rankine cycle.

  3. Experimental analysis of heat transfer characteristics and pressure drop through screen regenerative heat exchangers. Master's thesis

    SciTech Connect (OSTI)

    Wiese, J.L.

    1993-12-01

    This study investigated the effect on heat transfer and friction characteristics for screen regenerative heat exchangers with the screen thickness reduced by rolling. The experiments were performed on 250 and 325 mesh, 304 stainless steel screen using helium gas. Reynolds numbers, based on hydraulic radius, Re, were between 10 and 100. Both the Colburn factor, StPr(2/3), and friction factor, f, decreased as the screen thickness was reduced. A correlation was found for predicting friction factor, f. The drag coefficient per screen remained nearly unchanged for thicknesses reduced not more than 30 percent. The decrease in Colburn factor was significant for Re less than 40. For Re between 40 and 100 the decrease in Colburn factor was less than the experimental uncertainty. Regenerative Cooling, Regenerators, Cryogenic Engines, Screens (Woven Materials), Mesh, Stirling Cycle.

  4. Numerical Study on Crossflow Printed Circuit Heat Exchanger for Advanced Small Modular Reactors

    SciTech Connect (OSTI)

    Yoon, Su-Jong; Sabharwall, Piyush; Kim, Eung-Soo

    2014-03-01

    Various fluids such as water, gases (helium), molten salts (FLiNaK, FLiBe) and liquid metal (sodium) are used as a coolant of advanced small modular reactors (SMRs). The printed circuit heat exchanger (PCHE) has been adopted as the intermediate and/or secondary heat exchanger of SMR systems because this heat exchanger is compact and effective. The size and cost of PCHE can be changed by the coolant type of each SMR. In this study, the crossflow PCHE analysis code for advanced small modular reactor has been developed for the thermal design and cost estimation of the heat exchanger. The analytical solution of single pass, both unmixed fluids crossflow heat exchanger model was employed to calculate a two dimensional temperature profile of a crossflow PCHE. The analytical solution of crossflow heat exchanger was simply implemented by using built in function of the MATLAB program. The effect of fluid property uncertainty on the calculation results was evaluated. In addition, the effect of heat transfer correlations on the calculated temperature profile was analyzed by taking into account possible combinations of primary and secondary coolants in the SMR systems. Size and cost of heat exchanger were evaluated for the given temperature requirement of each SMR.

  5. Generator-Absorber heat exchange transfer apparatus and method using an intermediate liquor

    DOE Patents [OSTI]

    Phillips, Benjamin A.; Zawacki, Thomas S.

    1996-11-05

    Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use the working solution of the absorption system for the heat transfer medium where the working solution has an intermediate liquor concentration.

  6. MULTI-SCALE MODELING AND APPROXIMATION ASSISTED OPTIMIZATION OF BARE TUBE HEAT EXCHANGERS

    SciTech Connect (OSTI)

    Bacellar, Daniel; Ling, Jiazhen; Aute, Vikrant; Radermacher, Reinhard; Abdelaziz, Omar

    2014-01-01

    Air-to-refrigerant heat exchangers are very common in air-conditioning, heat pump and refrigeration applications. In these heat exchangers, there is a great benefit in terms of size, weight, refrigerant charge and heat transfer coefficient, by moving from conventional channel sizes (~ 9mm) to smaller channel sizes (< 5mm). This work investigates new designs for air-to-refrigerant heat exchangers with tube outer diameter ranging from 0.5 to 2.0mm. The goal of this research is to develop and optimize the design of these heat exchangers and compare their performance with existing state of the art designs. The air-side performance of various tube bundle configurations are analyzed using a Parallel Parameterized CFD (PPCFD) technique. PPCFD allows for fast-parametric CFD analyses of various geometries with topology change. Approximation techniques drastically reduce the number of CFD evaluations required during optimization. Maximum Entropy Design method is used for sampling and Kriging method is used for metamodeling. Metamodels are developed for the air-side heat transfer coefficients and pressure drop as a function of tube-bundle dimensions and air velocity. The metamodels are then integrated with an air-to-refrigerant heat exchanger design code. This integration allows a multi-scale analysis of air-side performance heat exchangers including air-to-refrigerant heat transfer and phase change. Overall optimization is carried out using a multi-objective genetic algorithm. The optimal designs found can exhibit 50 percent size reduction, 75 percent decrease in air side pressure drop and doubled air heat transfer coefficients compared to a high performance compact micro channel heat exchanger with same capacity and flow rates.

  7. Advanced Heat/Mass Exchanger Technology for Geothermal and solar...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    important source of irreversibility in a power plant is the heatmass exchange process. ... which translates to an improvement in power plant thermal efficiency. * Compressed ...

  8. EERE Success Story-3D Printing Enables New Generation of Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy 3D Printing Enables New Generation of Heat Exchangers EERE Success Story-3D Printing Enables New Generation of Heat Exchangers March 17, 2016 - 10:32am Addthis The University of Maryland used direct metal printing—a 3D printing technology—to manufacture a unique miniaturized air-to-refrigerant heat exchanger as a single, continuous piece. Image: University of Maryland, Center for Environmental Energy Engineering. The University of Maryland used direct metal

  9. Project Profile: High-Temperature Particle Heat Exchanger for sCO2 Power

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cycles (SuNLaMP) | Department of Energy High-Temperature Particle Heat Exchanger for sCO2 Power Cycles (SuNLaMP) Project Profile: High-Temperature Particle Heat Exchanger for sCO2 Power Cycles (SuNLaMP) Funding Program: SuNLaMP SunShot Subprogram: CSP Location: Sandia National Laboratory, Albuquerque, NM SunShot Award Amount: $4,586,967 This project is designing, developing, and testing a supercritical carbon dioxide (sCO2) heat exchanger that operates at temperatures higher than 720°C and

  10. SEP Request for Approval Form 1 - Modeling of Data at Finer Intervals...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    SEP Request for Approval Form 1 - Modeling of Data at Finer Intervals than Weekly File SEP-Request-for-Approval-Form-1Modeling-of-Data-at-Finer-Intervals-than-Weekly.docx More ...

  11. Progress Report for Diffusion Welding of the NGNP Process Application Heat Exchangers

    SciTech Connect (OSTI)

    R.E. Mizia; D.E. Clark; M.V. Glazoff; T.E. Lister; T.L. Trowbridge

    2011-12-01

    The U.S. Department of Energy selected the high temperature gas-cooled reactor as the basis for the Next Generation Nuclear Plant (NGNP). The NGNP will demonstrate the use of nuclear power for electricity, hydrogen production, and process heat applications. The NGNP Project is currently investigating the use of metallic, diffusion welded, compact heat exchangers to transfer heat from the primary (reactor side) heat transport system to the secondary heat transport system. An intermediate heat exchanger will transfer this heat to downstream applications such as hydrogen production, process heat, and electricity generation. The channeled plates that make up the heat transfer surfaces of the intermediate heat exchanger will have to be assembled into an array by diffusion welding. This report describes the preliminary results of a scoping study that evaluated the diffusion welding process parameters and the resultant mechanical properties of diffusion welded joints using Alloy 800H. The long-term goal of the program is to progress towards demonstration of small heat exchanger unit cells fabricated with diffusion welds. Demonstration through mechanical testing of the unit cells will support American Society of Mechanical Engineers rules and standards development, reduce technical risk, and provide proof of concept for heat exchanger fabrication methods needed to deploy heat exchangers in several potential NGNP configurations.1 Researchers also evaluated the usefulness of modern thermodynamic and diffusion computational tools (Thermo-Calc and Dictra) in optimizing the parameters for diffusion welding of Alloy 800H. The modeling efforts suggested a temperature of 1150 C for 1 hour with an applied pressure of 5 MPa using 15 {micro}m nickel foil as joint filler to reduce chromium oxidation on the welded surfaces. Good agreement between modeled and experimentally determined concentration gradients was achieved

  12. Design Option of Heat Exchanger for the Next Generation Nuclear Plant

    SciTech Connect (OSTI)

    Eung Soo Kim; Chang Oh

    2008-09-01

    The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTGRS) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale of a few hundred megawatts electric and hydrogen production. The power conversion system (PCS) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTGRS to provide higher efficiencies than can be achieved in the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. As part of the system integration of the VHTGRS and hydrogen production plant, the intermediate heat exchanger is used to transfer the process heat from VHTGRS to hydrogen plant. Therefore, the design and configuration of the intermediate heat exchanger are very important. This paper will include analysis of one stage versus two stage heat exchanger design configurations and thermal stress analyses of a printed circuit heat exchanger, helical coil heat exchanger, and shell/tube heat exchanger.

  13. BTO Awards Small Business Grants for Lighting, Building-Integrated Heat and Moisture Exchange Technology

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy Office of Science has awarded four Small Business Innovation Research (SBIR) grants targeting advances in solid-state lighting (SSL) and building-integrated heat and moisture exchange technology.

  14. Building-Integrated Heat & Moisture Exchange (STTR Phase 1 and 2) |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy STTR Phase 1 and 2) Building-Integrated Heat & Moisture Exchange (STTR Phase 1 and 2) 1 of 2 Building-integrated heat and moisture exchanger, the AirFlow(tm) Panel, installed for evaluation at Lawrence Berkeley National Lab. Image: Architectural Applications 2 of 2 A schematic of the AirFlow(tm) Panel developed by Architectural Applications. Image: Architectural Applications Lead Performer: Architectural Applications - Portland, OR Partners: -- Lawrence Berkeley

  15. Numerical simulation of gas dynamics and heat exchange tasks in fuel assemblies of the nuclear reactors

    SciTech Connect (OSTI)

    Zhuchenko, S. V.

    2014-11-12

    This report presents a PC-based program for solution gas dynamics and heat exchange mathematical tasks in fuel assemblies of the fast-neutron nuclear reactors. A fuel assembly consisting of bulk heat-generating elements, which are integrated together by the system of supply and pressure manifolds, is examined. Spherical heat-generating microelements, which contain nuclear fuel, are pulled into the heat-generating elements. Gaseous coolant proceed from supply manifolds to heat-generating elements, where it withdraws the nuclear reaction heat and assembles in pressure manifolds.

  16. Liquid Salt Heat Exchanger Technology for VHTR Based Applications...

    Office of Scientific and Technical Information (OSTI)

    The third task focuses integral testing of flowing liquid salts in a heat transfer... Country of Publication: United States Language: English Subject: 21 SPECIFIC NUCLEAR ...

  17. Thermal behavior of spiral fin-and-tube heat exchanger having fly ash deposit

    SciTech Connect (OSTI)

    Nuntaphan, Atipoang; Kiatsiriroat, Tanongkiat

    2007-08-15

    This research investigates the effect of fly-ash deposit on thermal performance of a cross-flow heat exchanger having a set of spiral finned-tubes as a heat transfer surface. A stream of warm air having high content of fly-ash is exchanging heat with a cool water stream in the tubes. In this study, the temperature of the heat exchanger surface is lower than the dew point temperature of air, thus there is condensation of moisture in the air stream on the heat exchanger surface. The affecting parameters such as the fin spacing, the air mass flow rate, the fly-ash mass flow rate and the inlet temperature of warm air are varied while the volume flow rate and the inlet temperature of the cold water stream are kept constant at 10 l/min and 5 C, respectively. From the experiment, it is found that as the testing period is shorter than 8 h the thermal resistance due to the fouling increases with time. Moreover, the deposit of fly-ash on the heat transfer surface is directly proportional to the dust-air ratio and the amount of condensate on heat exchange surface. However, the deposit of fly-ash is inversely proportional to the fin spacing. The empirical model for evaluating the thermal resistance is also developed in this work and the simulated results agree well with those of the measured data. (author)

  18. Radiation from Large Gas Volumes and Heat Exchange in Steam Boiler Furnaces

    SciTech Connect (OSTI)

    Makarov, A. N.

    2015-09-15

    Radiation from large cylindrical gas volumes is studied as a means of simulating the flare in steam boiler furnaces. Calculations of heat exchange in a furnace by the zonal method and by simulation of the flare with cylindrical gas volumes are described. The latter method is more accurate and yields more reliable information on heat transfer processes taking place in furnaces.

  19. Effect of Channel Configurations for Tritium Transfer in Printed Circuit Heat Exchangers

    SciTech Connect (OSTI)

    Chang Oh; Eung Kim; Robert Shrake; Mike Patterson

    2009-05-01

    The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTR) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale of a few hundred megawatts electric and hydrogen production. The power conversion system (PCS) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTR to provide higher efficiencies than can be achieved in the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. In the VHTR system, an intermediate heat exchanger (IHX), which transfers heat from the reactor core to the electricity or hydrogen production system is one key component, and its effectiveness is directly related to the system overall efficiency. In the VHTRs, the gas fluids used for coolant generally have poor heat transfer capability, so it requires very large surface area for a given condition. For this reason, a compact heat exchanger (CHE), which is widely used in industry especially for gasto-gas or gas-to-liquid heat exchange is considered as a potential candidate for an IHX replacing the classical shell and tube type heat exchanger. A compact heat exchanger is arbitrary referred to be a heat exchanger having a surface area density greater than 700 m2/m3. The compactness is usually achieved by fins and micro-channels, and leads to the enormous heat transfer enhancement and size reduction. The surface area density is the

  20. Global Heat Exchangers Market to be driven by Rapidly Expanding...

    Open Energy Info (EERE)

    by Rapidly Expanding End-user Industries Home > Groups > Renewable Energy RFPs Wayne31jan's picture Submitted by Wayne31jan(150) Contributor 2 July, 2015 - 00:43 Heat...

  1. Building America Case Study: Foundation Heat Exchanger, Oak Ridge...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for a building is a function of the building's space-conditioning and water-heating loads. ... At House 1, the hybrid FHXHGHX system was installed in a 300 linear foot excavation, and ...

  2. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    SciTech Connect (OSTI)

    Edward Levy; Harun Bilirgen; John DuPoint

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: (1) An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing high-moisture, low rank coals. (2) Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. (3) Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. (4) Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. (5) Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. (6) Condensed flue gas water treatment needs and costs. (7) Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. (8) Results of cost-benefit studies of condensing heat exchangers.

  3. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    SciTech Connect (OSTI)

    Levy, Edward; Bilirgen, Harun; DuPont, John

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: • An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing highmoisture, low rank coals. • Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. • Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. • Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. • Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. • Condensed flue gas water treatment needs and costs. • Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. • Results of cost-benefit studies of condensing heat exchangers.

  4. Evaluation Methodology for Advance Heat Exchanger Concepts Using Analytical Hierarchy Process

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim

    2012-07-01

    The primary purpose of this study is to aid in the development and selection of the secondary/process heat exchanger (SHX) for power production and process heat application for a Next Generation Nuclear Reactors (NGNR). The potential options for use as an SHX are explored such as shell and tube, printed circuit heat exchanger. A shell and tube (helical coiled) heat exchanger is a recommended for a demonstration reactor because of its reliability while the reactor design is being further developed. The basic setup for the selection of the SHX has been established with evaluation goals, alternatives, and criteria. This study describes how these criteria and the alternatives are evaluated using the analytical hierarchy process (AHP).

  5. Heat Exchanger Design Options and Tritium Transport Study for the VHTR System

    SciTech Connect (OSTI)

    Chang H. Oh; Eung S. Kim

    2008-09-01

    This report presents the results of a study conducted to consider heat exchanger options and tritium transport in a very high temperature reactor (VHTR) system for the Next Generation Nuclear Plant Project. The heat exchanger options include types, arrangements, channel patterns in printed circuit heat exchangers (PCHE), coolant flow direction, and pipe configuration in shell-and-tube designs. Study considerations include: three types of heat exchanger designs (PCHE, shell-and-tube, and helical coil); single- and two-stage unit arrangements; counter-current and cross flow configurations; and straight pipes and U-tube designs in shell-and-tube type heat exchangers. Thermal designs and simple stress analyses were performed to estimate the heat exchanger options, and the Finite Element Method was applied for more detailed calculations, especially for PCHE designs. Results of the options study show that the PCHE design has the smallest volume and heat transfer area, resulting in the least tritium permeation and greatest cost savings. It is theoretically the most reliable mechanically, leading to a longer lifetime. The two-stage heat exchanger arrangement appears to be safer and more cost effective. The recommended separation temperature between first and second stages in a serial configuration is 800oC, at which the high temperature unit is about one-half the size of the total heat exchanger core volume. Based on simplified stress analyses, the high temperature unit will need to be replaced two or three times during the plants lifetime. Stress analysis results recommend the off-set channel pattern configuration for the PCHE because stress reduction was estimated at up to 50% in this configuration, resulting in a longer lifetime. The tritium transport study resulted in the development of a tritium behavior analysis code using the MATLAB Simulink code. In parallel, the THYTAN code, previously performed by Ohashi and Sherman (2007) on the Peach Bottom data, was revived

  6. Review of Current Experience on Intermediate Heat Exchanger (IHX) and A Recommended Code Approach

    SciTech Connect (OSTI)

    Duane Spencer; Kevin McCoy

    2010-02-02

    The purpose of the ASME/DOE Gen IV Task 7 Part I is to review the current experience on various high temperature reactor intermediate heat exchanger (IHX) concepts. There are several different IHX concepts that could be envisioned for HTR/VHTR applications in a range of temperature from 850C to 950C. The concepts that will be primarily discussed herein are: (1) Tubular Helical Coil Heat Exchanger (THCHE); (2) Plate-Stamped Heat Exchanger (PSHE); (3) Plate-Fin Heat Exchanger (PFHE); and (4) Plate-Machined Heat Exchanger (PMHE). The primary coolant of the NGNP is potentially subject to radioactive contamination by the core as well as contamination from the secondary loop fluid. To isolate the radioactivity to minimize radiation doses to personnel, and protect the primary circuit from contamination, intermediate heat exchangers (IHXs) have been proposed as a means for separating the primary circuit of the NGNP (Next Generation Nuclear Plant) or other process heat application from the remainder of the plant. This task will first review the different concepts of IHX that could be envisioned for HTR/VHTR applications in a range of temperature from 850 to 950 C. This will cover shell-and-tube and compact designs (including the platefin concept). The review will then discuss the maturity of the concepts in terms of design, fabricability and component testing (or feedback from experience when applicable). Particular attention will be paid to the feasibility of developing the IHX concepts for the NGNP with operation expected in 2018-2021. This report will also discuss material candidates for IHX applications and will discuss specific issues that will have to be addressed in the context of the HTR design (thermal aging, corrosion, creep, creep-fatigue, etc). Particular attention will be paid to specific issues associated with operation at the upper end of the creep regime.

  7. Woven graphite fiber structures for use in ultra-light weigth heat exchangers

    SciTech Connect (OSTI)

    Hemrick, James Gordon; Lara-Curzio, Edgar; Loveland, Erick R; Sharp, Keith W; Schartow, Robert

    2011-01-01

    As part of U.S. Department of Energy efforts to find novel approaches for thermal management and heat recovery, work was undertaken at Oak Ridge National Laboratory (ORNL) to investigate the use of graphite-based materials for heat exchanger and thermal management devices. From this effort, lightweight, robust woven graphite-fiber structures were developed which provide high conductivity paths along the direction of the graphite fibers. These structures were produced and characterized for air permeability/pressure drop and thermal (heat transfer) performance. Results have been shown to be favorable for using such structures in ultra-light weight heat exchanger applications such as vehicle radiators or other areas where light weight, compact, conformable heat transfer devices are needed.

  8. HEAT TRANSFER ANALYSIS FOR ION-EXCHANGE COLUMN SYSTEM

    SciTech Connect (OSTI)

    Lee, S.; King, W.

    2011-05-23

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed, inadvertent column drainage, and loss of active cooling in the column. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature.

  9. Heat exchange in a multi-cavity volumetric solar receiver

    SciTech Connect (OSTI)

    Carotenuto, A.; Ruocco, G.; Reale, F. )

    1991-01-01

    The concept of a multi-cavity volumetric solar receiver is very attractive for the profitability of certain of its characteristics such as high efficiency and economy. The absorber is based on a pack of small ceramic cavities which intercept and absorb the inherent high solar flux reflected from an array of mirrors. Atmospheric air acts as a coolant medium when it is drawn through the pack. A model for an overall heat transfer performance of the receiver is given and numerically solved.

  10. Metallic heat exchangers for coal gasification. Final report

    SciTech Connect (OSTI)

    Natesan, K.

    1984-05-01

    A high-temperature corrosion program is being conducted to evaluate the corrosion behavior of selected metallic alloys and coatings in mixed-gas atmospheres for application in heat recovery systems of coal gasification schemes. The experiments conducted with internally air-cooled specimens have established three key variables, namely the gas temperature, metal temperature, and gas chemistry. In addition, the alloy chemistry and exposure time have a strong influence on the corrosion scale morphologies and metal recession rates. The results showed that the scale growth in carbon steel and low- to medium-chromium steels is predominantly linear with time. Selection of these materials will be primarily based upon acceptable corrosion wastage rate. On the other hand, high-chromium alloys can develop thin oxide scales resulting in negligible wastage via corrosion, but are susceptible to accelerated corrosion in mixed-gas atmospheres.

  11. Condensing heat-exchanger systems for oil-fired residential/commercial furnaces and boilers Phase I and II

    SciTech Connect (OSTI)

    Ball, D.A.; White, E.L.; Lux, J.J. Jr.; Locklin, D.W.

    1982-10-01

    The objective of the program reported was to provide supporting research to aid in the development and demonstration of oil-fired residential and commercial heating equipment that will operate in a condensing mode. Materials for heat exchangers are screened through coupon testing in a furnace simulator test rig and in an alternate immersion test rig. Condensate from oil-fired systems is characterized. Some general issues related to field application are treated, including heat exchanger fouling, venting of combustion gases, disposal of flue gas condensate, other means of condensate disposal, and evaluation of codes and standards. A heat transfer analysis is presented for general heat exchangers. (LEW)

  12. Additive Manufacturing for Cost Efficient Production of Compact Ceramic Heat Exchangers and Recuperators

    SciTech Connect (OSTI)

    Shulman, Holly; Ross, Nicole

    2015-10-30

    An additive manufacture technique known as laminated object manufacturing (LOM) was used to fabricate compact ceramic heat exchanger prototypes. LOM uses precision CO2 laser cutting of ceramic green tapes, which are then precision stacked to build a 3D object with fine internal features. Modeling was used to develop prototype designs and predict the thermal response, stress, and efficiency in the ceramic heat exchangers. Build testing and materials analyses were used to provide feedback for the design selection. During this development process, laminated object manufacturing protocols were established. This included laser optimization, strategies for fine feature integrity, lamination fluid control, green handling, and firing profile. Three full size prototypes were fabricated using two different designs. One prototype was selected for performance testing. During testing, cross talk leakage prevented the application of a high pressure differential, however, the prototype was successful at withstanding the high temperature operating conditions (1300 °F). In addition, analysis showed that the bulk of the part did not have cracks or leakage issues. This led to the development of a module method for next generation LOM heat exchangers. A scale-up cost analysis showed that given a purpose built LOM system, these ceramic heat exchangers would be affordable for the applications.

  13. Interface Exchange as an Indicator for Eddy Heat Transport

    SciTech Connect (OSTI)

    Petersen, Mark R.; Williams, Sean J.; Hecht, Matthew W.; Maltrud, Mathew E.; Hamann, Bernd; Patchett, John M.; Ahrens, James P.

    2012-06-12

    The ocean contains many large-scale, long-lived vortices, called mesoscale eddies, that are believed to have a role in the transport and redistribution of salt, heat, and nutrients throughout the ocean. Determining this role, however, has proven to be a challenge, since the mechanics of eddies are only partly understood; a standard definition for these ocean eddies does not exist and, therefore, scientifically meaningful, robust methods for eddy extraction, characterization, tracking and visualization remain a challenge. In order to shed light on the nature and potential roles of eddies, we have combined our previous research on eddy identification and tracking, and have used those approaches as the basis for analysis-driven computational experiments on the nature of eddies. Based on the resulting visualizations of eddy behavior, we have devised a new metric to characterize the transfer of water into and out of eddies across their boundary, and have developed visualization methods for this new metric to provide clues about the role eddies play in the global ocean and, potentially, climate change.

  14. Hybrid heat exchange for the compression capture of CO2 from recirculated flue gas

    SciTech Connect (OSTI)

    Oryshchyn, Danylo B.; Ochs, Thomas L.; Summers, Cathy A.

    2004-01-01

    An approach proposed for removal of CO2 from flue gas cools and compresses a portion of a recirculated flue-gas stream, condensing its volatile materials for capture. Recirculating the flue gas concentrates SOx, H2O and CO2 while dramatically reducing N2 and NOx, enabling this approach, which uses readily available industrial components. A hybrid system of indirect and direct-contact heat exchange performs heat and mass transfer for pollutant removal and energy recovery. Computer modeling and experimentation combine to investigate the thermodynamics, heat and mass transfer, chemistry and engineering design of this integrated pollutant removal (IPR) system.

  15. Waking the sleeping giant: Introducing new heat exchanger technology into the residential air-conditioning marketplace

    SciTech Connect (OSTI)

    Chapp, T.; Voss, M.; Stephens, C.

    1998-07-01

    The Air Conditioning Industry has made tremendous strides in improvements to the energy efficiency and reliability of its product offerings over the past 40 years. These improvement can be attributed to enhancements of components, optimization of the energy cycle, and modernized and refined manufacturing techniques. During this same period, energy consumption for space cooling has grown significantly. In January of 1992, the minimum efficiency requirement for central air conditioning equipment was raised to 10 SEER. This efficiency level is likely to increase further under the auspices of the National Appliance Energy Conservation Act (NAECA). A new type of heat exchanger was developed for air conditioning equipment by Modine Manufacturing Company in the early 1990's. Despite significant advantages in terms of energy efficiency, dehumidification, durability, and refrigerant charge there has been little interest expressed by the air conditioning industry. A cooperative effort between Modine, various utilities, and several state energy offices has been organized to test and demonstrate the viability of this heat exchanger design throughout the nation. This paper will review the fundamentals of heat exchanger design and document this simple, yet novel technology. These experiences involving equipment retrofits have been documented with respect to the performance potential of air conditioning system constructed with PF{trademark} Heat Exchangers (generically referred to as microchannel heat exchangers) from both an energy efficiency as well as a comfort perspective. The paper will also detail the current plan to introduce 16 to 24 systems into an extended field test throughout the US which commenced in the Fall of 1997.

  16. Parametric Sensivity Study of Operating and Design Variables in Wellbore Heat Exchangers

    SciTech Connect (OSTI)

    G. Michael Shook; Gopi Nalla; Gregory L. Mines; K. Kit Bloomfield

    2004-05-01

    This report documents the results of an extensive sensitivity study conducted by the Idaho National Engineering and Environmental Laboratory. This study investigated the effects of various operating and design parameters on wellbore heat exchanger performance to determine conditions for optimal thermal energy extraction and evaluate the potential for using a wellbore heat exchanger model for power generation. Variables studied included operational parameters such as circulation rates, wellbore geometries and working fluid properties, and regional properties including basal heat flux and formation rock type. Energy extraction is strongly affected by fluid residence time, heat transfer contact area, and formation thermal properties. Water appears to be the most appropriate working fluid. Aside from minimal tubing insulation, tubing properties are second order effects. On the basis of the sensitivity study, a best case model was simulated and the results compared against existing low-temperature power generation plants. Even assuming ideal work conversion to electric power, a wellbore heat exchange model cannot generate 200 kW (682.4e+3 BTU/h) at the onset of pseudosteady state. Using realistic conversion efficiency, the method is unlikely to generate 50 kW (170.6e+3 BTU/h).

  17. Parametric Sensitivity Study of Operating and Design Variables in Wellbore Heat Exchangers

    SciTech Connect (OSTI)

    Nalla, G.; Shook, G.M.; Mines, G.L.; Bloomfield, K.K.

    2004-05-01

    This report documents the results of an extensive sensitivity study conducted by the Idaho National Engineering and Environmental Laboratory. This study investigated the effects of various operating and design parameters on wellbore heat exchanger performance to determine conditions for optimal thermal energy extraction and evaluate the potential for using a wellbore heat exchanger model for power generation. Variables studied included operational parameters such as circulation rates, wellbore geometries and working fluid properties, and regional properties including basal heat flux and formation rock type. Energy extraction is strongly affected by fluid residence time, heat transfer contact area, and formation thermal properties. Water appears to be the most appropriate working fluid. Aside from minimal tubing insulation, tubing properties are second order effects. On the basis of the sensitivity study, a best case model was simulated and the results compared against existing low-temperature power generation plants. Even assuming ideal work conversion to electric power, a wellbore heat exchange model cannot generate 200 kW (682.4e+3 BTU/h) at the onset of pseudosteady state. Using realistic conversion efficiency, the method is unlikely to generate 50 kW (170.6e+3 BTU/h).

  18. Micro-scale heat-exchangers for Joule-Thomson cooling.

    SciTech Connect (OSTI)

    Gross, Andrew John

    2014-01-01

    This project focused on developing a micro-scale counter flow heat exchangers for Joule-Thomson cooling with the potential for both chip and wafer scale integration. This project is differentiated from previous work by focusing on planar, thin film micromachining instead of bulk materials. A process will be developed for fabricating all the devices mentioned above, allowing for highly integrated micro heat exchangers. The use of thin film dielectrics provides thermal isolation, increasing efficiency of the coolers compared to designs based on bulk materials, and it will allow for wafer-scale fabrication and integration. The process is intended to implement a CFHX as part of a Joule-Thomson cooling system for applications with heat loads less than 1mW. This report presents simulation results and investigation of a fabrication process for such devices.

  19. Power module packaging with double sided planar interconnection and heat exchangers

    DOE Patents [OSTI]

    Liang, Zhenxian; Marlino, Laura D.; Ning, Puqi; Wang, Fei

    2015-05-26

    A double sided cooled power module package having a single phase leg topology includes two IGBT and two diode semiconductor dies. Each IGBT die is spaced apart from a diode semiconductor die, forming a switch unit. Two switch units are placed in a planar face-up and face-down configuration. A pair of DBC or other insulated metallic substrates is affixed to each side of the planar phase leg semiconductor dies to form a sandwich structure. Attachment layers are disposed on outer surfaces of the substrates and two heat exchangers are affixed to the substrates by rigid bond layers. The heat exchangers, made of copper or aluminum, have passages for carrying coolant. The power package is manufactured in a two-step assembly and heating process where direct bonds are formed for all bond layers by soldering, sintering, solid diffusion bonding or transient liquid diffusion bonding, with a specially designed jig and fixture.

  20. Technology Development Roadmap for the Advanced High Temperature Reactor Secondary Heat Exchanger

    SciTech Connect (OSTI)

    P. Sabharwall; M. McCllar; A. Siahpush; D. Clark; M. Patterson; J. Collins

    2012-09-01

    This Technology Development Roadmap (TDRM) presents the path forward for deploying large-scale molten salt secondary heat exchangers (MS-SHX) and recognizing the benefits of using molten salt as the heat transport medium for advanced high temperature reactors (AHTR). This TDRM will aid in the development and selection of the required heat exchanger for: power production (the first anticipated process heat application), hydrogen production, steam methane reforming, methanol to gasoline production, or ammonia production. This TDRM (a) establishes the current state of molten salt SHX technology readiness, (b) defines a path forward that systematically and effectively tests this technology to overcome areas of uncertainty, (c) demonstrates the achievement of an appropriate level of maturity prior to construction and plant operation, and (d) identifies issues and prioritizes future work for maturing the state of SHX technology. This study discusses the results of a preliminary design analysis of the SHX and explains the evaluation and selection methodology. An important engineering challenge will be to prevent the molten salt from freezing during normal and off-normal operations because of its high melting temperature (390°C for KF ZrF4). The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The need for efficiency, compactness, and safety challenge the capabilities of existing heat exchanger technology. The description of potential heat exchanger configurations or designs (such as printed circuit, spiral or helical coiled, ceramic, plate and fin, and plate type) were covered in an earlier report (Sabharwall et al. 2011). Significant future work, much of which is suggested in this report, is needed before the benefits and full potential of the AHTR can be realized. The execution of this TDRM will focuses

  1. Liquid metal heat exchanger for efficient heating of soils and geologic formations

    DOE Patents [OSTI]

    DeVault, Robert C [Knoxville, TN; Wesolowski, David J [Kingston, TN

    2010-02-23

    Apparatus for efficient heating of subterranean earth includes a well-casing that has an inner wall and an outer wall. A heater is disposed within the inner wall and is operable within a preselected operating temperature range. A heat transfer metal is disposed within the outer wall and without the inner wall, and is characterized by a melting point temperature lower than the preselected operating temperature range and a boiling point temperature higher than the preselected operating temperature range.

  2. Directly connected heat exchanger tube section and coolant-cooled structure

    DOE Patents [OSTI]

    Chainer, Timothy J; Coico, Patrick A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Steinke, Mark E

    2014-04-01

    A cooling apparatus for an electronics rack is provided which includes an air-to-liquid heat exchanger, one or more coolant-cooled structures and a tube. The heat exchanger, which is associated with the electronics rack and disposed to cool air passing through the rack, includes a plurality of distinct, coolant-carrying tube sections, each tube section having a coolant inlet and a coolant outlet, one of which is coupled in fluid communication with a coolant loop to facilitate flow of coolant through the tube section. The coolant-cooled structure(s) is in thermal contact with an electronic component(s) of the rack, and facilitates transfer of heat from the component(s) to the coolant. The tube connects in fluid communication one coolant-cooled structure and the other of the coolant inlet or outlet of the one tube section, and facilitates flow of coolant directly between that coolant-carrying tube section of the heat exchanger and the coolant-cooled structure.

  3. An analytical oscillating-flow thermal analysis of the heat exchangers and regenerator in Stirling machines

    SciTech Connect (OSTI)

    Monte, F. de; Galli, G.; Marcotullio, F.

    1996-12-31

    A closed form-expression for the effectiveness of the heat exchangers and regenerator of a Stirling cycle machine is given. This result may be used in a simple way in order to evaluate their effect on the machine performance. The proposed method, indeed, allows the actual cycle gas temperatures in the heater and cooler to be obtained readily, once the geometry of the heater, cooler and regenerator is known and some quantities characterizing the engine dynamics (strokes, frequency and phase angle of the moving elements) and its heat-exchange processes (inlet temperatures of the heating and cooling fluids, and their volumetric flow rates) are measured. Thus, an immediate indication about the effectiveness of the heat exchangers and regenerator as well as about the machine thermal efficiency may be obtained. The availability of a closed-form expression for the heater, regenerator and cooler effectiveness is useful especially for those engines, like the free-piston Stirling engines, whose design requires the application of analytically based optimization criteria.

  4. Directly connected heat exchanger tube section and coolant-cooled structure

    DOE Patents [OSTI]

    Chainer, Timothy J.; Coico, Patrick A.; Graybill, David P.; Iyengar, Madhusudan K.; Kamath, Vinod; Kochuparambil, Bejoy J.; Schmidt, Roger R.; Steinke, Mark E.

    2015-09-15

    A method is provided for fabricating a cooling apparatus for cooling an electronics rack, which includes an air-to-liquid heat exchanger, one or more coolant-cooled structures, and a tube. The heat exchanger is associated with the electronics rack and disposed to cool air passing through the rack, includes a plurality of coolant-carrying tube sections, each tube section having a coolant inlet and outlet, one of which is coupled in fluid communication with a coolant loop to facilitate flow of coolant through the tube section. The coolant-cooled structure(s) is in thermal contact with an electronic component(s) of the rack, and facilitates transfer of heat from the component(s) to the coolant. The tube connects in fluid communication one coolant-cooled structure and the other of the coolant inlet or outlet of the one tube section, and facilitates flow of coolant directly between that coolant-carrying tube section of the heat exchanger and the coolant-cooled structure.

  5. Multiple pollutant removal using the condensing heat exchanger: Phase 1 final report, October 1995--July 1997

    SciTech Connect (OSTI)

    Bailey, R.T.; Jankura, B.J.; Kudlac, G.A.

    1998-06-01

    The Integrated Flue Gas Treatment (IFGT) system is a new concept whereby a Teflon{reg_sign} covered condensing heat exchanger is adapted to remove certain flue gas constitutents, both particulate and gaseous, while recovering low level heat. Phase 1 includes two experimental tasks. One task dealt principally with the pollutant removal capabilities of the IFGT at a scale of about 1.2MW{sub t}. The other task studied the durability of the Teflon{reg_sign} covering to withstand the rigors of abrasive wear by fly ash emitted as a result of coal combustion. The pollutant removal characteristics of the IFGT system were measured over a wide range of operating conditions. The coals tested included high, medium and low-sulfur coals. The flue gas pollutants studied included ammonia, hydrogen chloride, hydrogen fluoride, particulate, sulfur dioxide, gas phase and particle phase mercury and gas phase and particle phase trace elements. The particulate removal efficiency and size distribution was investigated. These test results demonstrated that the IFGT system is an effective device for both acid gas absorption and fine particulate collection. The durability of the Teflon{reg_sign} covered heat exchanger tubes was studied on a pilot-scale single-stage condensing heat exchanger (CHX{reg_sign}). Data from the test indicate that virtually no decrease in Teflon{reg_sign} thickness was observed for the coating on the first two rows of heat exchanger tubes, even at high inlet particulate loadings. Evidence of wear was present only at the microscopic level, and even then was very minor in severity.

  6. Foundation Heat Exchanger Final Report: Demonstration, Measured Performance, and Validated Model and Design Tool

    SciTech Connect (OSTI)

    Hughes, Patrick; Im, Piljae

    2012-04-01

    Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX

  7. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, K.H.; Ahluwalia, R.K.

    1994-10-18

    A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.

  8. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, Kwan H.; Ahluwalia, Rajesh K.

    1994-01-01

    A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.

  9. Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger

    DOE Patents [OSTI]

    Berry, G.F.; Minkov, V.; Petrick, M.

    1981-11-02

    A magnetohydrodynamic (MHD) power generating system is described in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

  10. Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger

    DOE Patents [OSTI]

    Berry, Gregory F.; Minkov, Vladimir; Petrick, Michael

    1988-01-01

    A magnetohydrodynamic (MHD) power generating system in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.