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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 289 records · Page 16

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NASA NTRS1991

Critical technology experiment results for lightweight space heat receiver

Critical technology experiments have been performed on thermal energy storage modules in support of the NASA Advanced Solar Dynamic Brayton Heat Receiver Program. The modules, wedge-shaped canisters containing lithium fluoride (LiF), were designed to minimize the mechanical stresses that occur during the phase change of the LiF. Nickel foam inserts were placed in two of the test canisters to provide thermal conductivity enhancement and to distribute the void volume throughout the canister. A procedure was developed for reducing the nickel oxides on the nickel foam to enhance the wicking ability of the foam. The canisters were filled with LiF and closure-welded at the NASA Lewis Research Center. Two canisters, one with a nickel foam insert, the other without an insert, were thermally cycled in various orientations in a fluidized bed furnace. Computer-aided tomography was successfully used to nondestructively determine void locations in the canisters. Finally, canister dimensional stability was measured after thermal cycling with an inspection fixture.

Schneider, Michael G.↗

NASA NTRS1991

Visualizing the thermal performance of heat pipes with thermochromic liquid crystals

A novel technique has been developed to visualized the thermal performance characteristics of simple low temperature heat pipes and thermosyphons. Copper heat pipes with internal, annular mesh wicks and charged with Refrigerant-12 were externally coated with thermochromic liquid crystal (TLC) paints. The thermally sensitive TLC coating reversibly changes color upon heating and readily permits visual identification of transient and steady state isotherms during low temperature operation. The start-up and operational behaviors of the heat pipe as well as the presence of non-condensible gases can be visually identified through a spectrum of color changes. A brief video demonstration illustrating heat pipe thermal performance characteristics has been developed and illustrates the utility of TLCs for visualizing thermal behavior.

Gunnerson, Fred S.↗

NASA NTRS1993

Making Porous Zirconia For Heat Pipes

Batch composition of processing schedule developed to produce porous zirconia having bubble point between 10 and 20 psi. Porous zirconia used to make wicks for heat pipes.

Liu, Felix↗

NASA NTRS1993

Single-Heater, Three-Zone Furnace

Temperature profile shaped with help of thermal barriers. Proposed furnace for use in experiments on growth of crystals of highly pure material in ampoule provides three temperature zones, yet contains only one heat-pipe liner and one heater and operates with only one controller. Three temperature zones established as thermal resistances of wicks and noncondensible gas reduces flows of heat into channel containing ampoule. Motion of ampoule along channel causes gradients of temperature to move along specimen in ampoule. Variety of three-zone temperature profiles in furnace created by changing thermal resistances of zones and injecting noncondensible gas at appropriate point. Furnace used for variety of experiments.

Gernert, Nelson J.↗

NASA NTRS1992

The VTRE Program: An overview

The Vented Tank Resupply Experiment (VTRE) Program is a NASA In-Space Technology Experiments Program (IN-STEP) that will develop, and fly a small, low cost space experiment to investigate, develop, and acquire needed data to extend and advance the technology of capillary vane fluid management devices to applications requiring direct venting of gas from tanks in low-gravity. GAS venting may be required for control of pressure, or to allow low-g fill of a tank with liquid while holding a constant tank back pressure by gas venting. Future space applications requiring these fluid management capabilities include both cryogenic and Earth storable fluid systems. The experiment is planned as a Shuttle Hitchhiker payload, and will be developed around two transparent tanks equipped with capillary vane devices between which a test liquid can be transferred. Experiments will be conducted for vented transfer, direct venting, stability of liquid positioning to accelerations within and significantly above the design values, and fluid reorientation by capillary wicking of liquid into the vane device following intentional liquid upset.

Bailey, William J.↗

NASA NTRS1993

Quons, an interpolation between Bose and Fermi oscillators

After a brief mention of Bose and Fermi oscillators and of particles which obey other types of statistics, including intermediate statistics, parastatistics, paronic statistics, anyon statistics, and infinite statistics, I discuss the statistics of 'quons' (pronounced to rhyme with muons), particles whose annihilation and creation operators obey the q-deformed commutation relation (the quon algebra or q-mutator) which interpolates between fermions and bosons. I emphasize that the operator for interaction with an external source must be an effective Bose operator in all cases. To accomplish this for parabose, parafermi and quon operators, I introduce parabose, parafermi, and quon Grassmann numbers, respectively. I also discuss interactions of non-relativistic quons, quantization of quon fields with antiparticles, calculation of vacuum matrix elements of relativistic quon fields, demonstration of the TCP theorem, cluster decomposition, and Wick's theorem for relativistic quon fields, and the failure of local commutativity of observables for relativistic quon fields. I conclude with the bound on the parameter q for electrons due to the Ramberg-Snow experiment.

Greenberg, O. W.↗

NASA NTRS1992

Heat pipe performance experiment

The objective of the heat pipe performance experiment is to answer questions about how heat pipe performance in space differs from heat pipe performance on the ground. This part of the experiment will attempt to account for the following: (1) gravity domination in ground testing; (2) surface tension domination in a microgravity environment; and (3) the effects of underfill and overfill. The secondary objective of the experiment is to obtain quantitative data for axial groove and porous wick heat pipes in a microgravity environment for comparison with the following: (1) analytical models; (2) ground test data; and (3) existing flight data.

Fleischman, George↗

NASA NTRS1993

A numerical analysis of high-temperature heat pipe startup from the frozen state

Continuum and rarefied vapor flows co-exist along the heat pipe length for most of the startup period. A two-region model is proposed in which the vapor flow in the continuum region is modeled by the compressible Navier-Stokes equations, and the vapor flow in the rarefied region is simulated by a self-diffusion model. The two vapor regions are linked with appropriate boundary conditions, and heat pipe wail, wick, and vapor flow are solved as a conjugate problem. The numerical solutions for the entire heat pipe startup process from the frozen state are compared with the corresponding experimental data with good agreement.

Cao, Y.↗

NASA NTRS1992

Design and development of a two-phase reservoir for the Capillary Pumped Loop (CAPL) Flight Experiment

The Capillary Pumped Loop (CAPL) Flight Experiment has undergone numerous design modifications to reflect recent changes in the thermal control system baselined for Earth Observation System (EOS) spacecraft. The experiment redesign has also allowed technological advances in two-phase fluid loop components to be incorporated. The experiment's reservoir is one of the components targeted for redesign. The design and development of a new reservoir for the CAPL Flight Experiment is discussed in this paper. A prototype reservoir is described, and a hydrodynamic analysis of its wick structure is included. Testing of the prototype reservoir is also discussed.

Wolf, David A.↗

NASA NTRS1994

Modular Cooling Components

Three modular heat-transfer components designed for use together or separately. Simple mechanical connections facilitate assembly of these and related heat-transfer components into cooling systems of various configurations, such as to cool laboratory equipment rearranged for different experiments. Components are clamp-on cold plate, cold plate attached to flexible heat pipe, and thermal-bus receptacle. Clamp-on cold plate moved to any convenient location for attachment of equipment cooled by it, then clamped onto thermal bus. Heat from equipment conducted through plate and into coolant. Thermal-bus receptacle integral with thermal bus. Includes part of thermal bus to which clamp-on cold plate attached, plus tapered socket into which condenser end of flexible heat pipe plugged. Thermal-bus receptacle includes heat-pipe wick structure using coolant in bus to enhance transfer of heat from cold plate.

Eastman, G. Yale↗

NASA NTRS1994

Computing Temperatures And Pressures Along Heat Pipes

NASA Lewis Research Center Heat Pipe, LERCHP, computer code developed to predict performances of heat pipes in steady state. Used as design software tool on personal computer or, with suitable calling routine, as subroutine for mainframe-computer radiator code. For accurate mathematical modeling of heat pipes, LERCHP makes variety of wick structures available to user. User chooses among several working fluids, for which monomer/dimer equilibrium considered. Vapor-flow algorithm treats compressibility and axially varying heat input. Facilitates determination of heat-pipe operating temperatures and heat-pipe limits encountered at specified heat input and environmental temperature. Written in FORTRAN 77.

Faker, K. W.↗

NASA NTRS1993

Transient studies of capillary-induced flow

This paper presents the numerical and experimental results of a study performed on the transient rise of fluid in a capillary tube. The capillary tube problem provides an excellent mechanism from which to launch an investigation into the transient flow of a fluid in a porous wick structure where capillary forces must balance both adverse gravitational effects and frictional losses. For the study, a capillary tube, initially charged with a small volume of water, was lowered into a pool of water. The behavior of the column of fluid during the transient that followed as more water entered the tube from the pool was both numerically and experimentally studied.

Reagan, M. K.↗

NASA NTRS1995

Long life 80Ah standard IPV NiH2 battery cell

A standard Nickel-Hydrogen (NiH2) Individual Pressure Vessel (IPV) battery cell is needed to meet future low cost, high performance mission requirements for NASA, military, and civil space programs. A common or standard cell design has evolved from the heritage of HST, Milstar, and other Air Force Mantech cell designs with substantial flight experience, while incorporating some of the historical COMSAT cell design features described in a previous NASA publication. Key features include slurry process nickel electrodes having high strength, long life and high yield (lower cost), and dual layer zircar separators for improved KOH retention, uniformality, and longer life. The cell design will have a zirconium oxide wall wick inside the pressure vessel to redistribute electrolyte and extend life. The slurry electrode will be 35 mils thick to take advantage of qualified cell mechanical configurations and proven assembly and activation techniques developed by Eagle Picher Industries (EPI) for the Hubble Space Telescope (HST) RNH-90-3 and 'Generic HST' RNH-90-5 cell designs with back-to-back nickel electrodes produced by the dry sinter process. The 80Ah common cell design can be scaled to meet capacity requirements from 60Ah to 100Ah. Producibility, commonality, and long life performance will be enhanced with the robust cell design described herein.

Armantrout, Jon D.↗

NASA NTRS1995

Unique features of a new nickel-hydrogen 2-cell CPV

Two-cell nickel-hydrogen common pressure vessel (CPV) units with some unusual design features have been successfully built and tested. The features of interest are half-normal platinum loading for the negative electrodes, the use of rabbit-ear terminals for a CPV unit, and the incorporation of a wall wick. The units have a nominal capacity of 20 Ah and are 3.5 inches in diameter. Electric performance data are provided. The data support the growing viability of the two-cell CPV design concept.

Wheeler, James R.↗

NASA NTRS1995

Apparatus for diffusion controlled dialysis under microgravity conditions

Apparatus for implementing crystal growth by allowing mixing of solutions under microgravity conditions includes a housing within which a number of pairs of chambers are formed. The chambers of each pair are aligned and a rotary valve is positioned between the chambers of each pair. When the valve is in a first position one chamber of each pair may communicate with the other chamber. A separate valve is provided for each pair of chambers so that each pair of chambers may be activated independently of the others and sequentially at selected intervals. Protein solution may be located within a small cavity in a cap which closes one of the chambers of a pair, and the cavity in the cap is closed by a dialysis membrane. The length of certain pairs of chambers may differ from the length of other pairs of chambers to optimize conditions for various dialysis productions, and wicking material may be incorporated into selected chambers for controlling the critical approach to supersaturation.

Carter, Daniel C.↗

NASA NTRS1994

Ionospheric convection during the magnetic storm of 20-21 March 1991

We report on the response of high-latitude ionospheric convection during the magnetic storm of March 20-21 1990. IMP-8 measurements of solar wind plasma and interplanetary magnetic field (IMF), ionospheric convection flow measurements from the Wick and Goose Bay coherent radars, EISCAT, Millstone Hill and Sondrestorm incoherent radars and three digisondes at Millstone Hill, Goose Bay and Qaanaaq are presented. Two intervals of particular interest have been indentified. The first starts with a storm sudden commencement at 2243 UT on March 20 and includes the ionospheric activity in the following 7 h. The response time of the ionospheric convection to the southward tuning of the IMF in the dusk to midnight local times is found to be approximately half that measured in a similar study at comparable local times during more normal solar wind conditions. A subsequent reconfiguration of the nightside convection pattern was also observed, although it was not possible to distinguish between effects due to possible changes in B(sub y) and effects due to substorm activity. The second interval, 1200-2100 UT 21 March 1990, included a southward turning of the IMF which resulted in the B(sub z) component becoming -10 nT. The response time on the dayside to this change in the IMF at the magnetopause was approximately 15 min to 30 min which is a factor of approximately 2 greater than those previously measured at higher latitudes. A movement of the nightside flow reversal, possibly driven by current systems associated with the substorm expansion phases, was observed, implying that the nightside convection pattern can be dominated by substorm activity.

Taylor, J. R.↗

NASA NTRS1995

The Cryogenic Test Bed experiments: Cryogenic heat pipe flight experiment CRYOHP (STS-53). Cryogenic two phase flight experiment CRYOTP (STS-62). Cryogenic flexible diode flight experiment CRYOFD

This paper presents an overview of the Cryogenic Test Bed (CTB) experiments including experiment results, integration techniques used, and lessons learned during integration, test and flight phases of the Cryogenic Heat Pipe Flight Experiment (STS-53) and the Cryogenic Two Phase Flight Experiment (OAST-2, STS-62). We will also discuss the Cryogenic Flexible Diode Heat Pipe (CRYOFD) experiment which will fly in the 1996/97 time frame and the fourth flight of the CTB which will fly in the 1997/98 time frame. The two missions tested two oxygen axially grooved heat pipes, a nitrogen fibrous wick heat pipe and a 2-methylpentane phase change material thermal storage unit. Techniques were found for solving problems with vibration from the cryo-collers transmitted through the compressors and the cold heads, and mounting the heat pipe without introducing parasitic heat leaks. A thermally conductive interface material was selected that would meet the requirements and perform over the temperature range of 55 to 300 K. Problems are discussed with the bi-metallic thermostats used for heater circuit protection and the S-Glass suspension straps originally used to secure the BETSU PCM in the CRYOTP mission. Flight results will be compared to 1-g test results and differences will be discussed.

Thienel, Lee↗

NASA NTRS1996

Mars global surveyor

The design and performance of a highly reliable, 20 volt nickel hydrogen battery compatible with existing NiCad Mars observer based spacecraft components and an 800 psi, zirconium wall wick Common Pressure Vessel (CPV) are discussed. The objectives of the design process are: to meet or exceed all PD requirements by using existing technologies; to have high reliability hardware and parallel fabrication of components; and low schedule risk configurations. This paper discusses the tests performed on the batteries (capacity, charge retention, random vib., pyro shock, energy density, and packing factor) and the results of the tests. In addition to the design discussion, a brief introduction on Mars Global Surveyor (MGS) Satellite objectives (NASA's next interplanetary mission) is also presented.

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