The long-range goal of this project is to understand and interpret atmospheric structures in the literal zone to improve the prediction of boundary layer processes on scales of 1 km to 100 km. This region of the atmosphere is complex, influenced by the competing effects of topography and differential heating. Large spatial and temporal variations in many fields are expected, but poorly predicted. The processes that control the distribution of aerosols, the formation, evolution and dissipation...
Topics: DTIC Archive, SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA, *MARINE ATMOSPHERES, BOUNDARY LAYER,...
The hazard classification procedures of TB 700-2 are improperly applied to pyrotechnics. Forty-six test methods were proposed as replacements for the currently applied methods. The proposed test methods were subjected to engineering review and analysis including the testing of two materials by six methods. Fifteen test methods were recommended for inclusion in a pyrotechnics supplement to TB 700-2.
Topics: DTIC Archive, Wilcox, Wayne R, GENERAL ELECTRIC CO BAY SAINT LOUIS MS ENGINEERING AND SCIENCE...
Thermal modeling is an important part of spacecraft design, especially where critical components have narrow operating temperature limits. For the Naval Postgraduate School?s NPSAT1 spacecraft, the lithium ion battery is the spacecraft component with the smallest temperature range of 0?C to 45?C during operation. Thermal analysis results, however, can only provide adequate results if there is sufficient fidelity in thermal modeling. Arguably, the values used in defining thermal coupling for...
Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA SPACE SYSTEMS ACADEMIC GROUP, *LITHIUM...
A numerical model is developed for the welding and subsequent loading of a fabricated structure. The model treats the weld process as a thermo- mechanical problem. A finite element formulation derived from the uncoupled thermal and mechanical energy balances forms the basis of the model. During the development of the thermal model, two significant problems are discussed. One is the material nonlinearity, which manifests itself in the temperature dependence of the thermal properties, and in the...
Topics: DTIC Archive, Hibbitt, Hugh D, BROWN UNIV PROVIDENCE RI DIV OF ENGINEERING, *STRUCTURES, *WELDS,...
ODTA detects temperature contact less, hence, it expands the upper usable temperature limit of DTA up to 3600 C accordingly suitable for studies of systems where enthalpic changes occur at high temperatures. Application of the computer graphics for the evaluation of the ODTA curves is demonstrated on melting of Y2OO3.A12O3 and Ya13-GdA1O3 systems. Measurement errors occurring at temperatures above 1900 C are pointed out and possibilities for their elimination or at least diminution are...
Topics: DTIC Archive, Caslavsky, Jaroslav L, ARMY LAB COMMAND WATERTOWN MA MATERIAL TECHNOLOGY LAB,...
Rhodium (III) acetylacetonate was investigated for its physical, thermal and optical properties. Ultraviolet-visible absorption spectra show absorption at 320 nm, 260 nm, and 210 nm. Density measurements yielded a value of 1.75 gram/cm cubed. Thermal characteristics were evaluated using differential thermal analysis(DTA). It was found that the compound is not volatile, decomposing upon heating. If heating rates are slower, decomposition is complete below the melting point. If the compound is...
Topics: DTIC Archive, Reisman,Arnold, NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF CHEMISTRY,...
An analytical study has been performed to assess the feasibility of using aerodynamically heated thermoelectric convertors to power RF proximity fuzes. The collective results of this study indicate that such a thermoelectric power supply is feasible for use with 20 mm projectiles and is compatible with the existing RF fuze circuit and safe arming distance requirements. A disc module concept has evolved from this study involving thin-film bismuth telluride as the basic thermoelectric element....
Topics: DTIC Archive, Eggers, Philip E, BATTELLE COLUMBUS DIV OH, *PROXIMITY FUZES, *THERMOELECTRIC POWER...
The technology of direct electrolysis of molten lunar regolith to produce oxygen and molten metal alloys has progressed greatly in the last few years. The development of long-lasting inert anodes and cathode designs as well as techniques for the removal of molten products from the reactor has been demonstrated. The containment of chemically aggressive oxide and metal melts is very difficult at the operating temperatures ca 1600 C. Containing the molten oxides in a regolith shell can solve this...
Topics: NASA Technical Reports Server (NTRS), DIMENSIONAL ANALYSIS, ELECTROLYSIS, LUNAR ROCKS, OXYGEN...
A study was performed to determine if a Design of Experiments (DOE)/Response Surface Methodology could be applied to on-orbit thermal analysis and produce a set of Response Surface Equations (RSE) that predict Orion vehicle temperatures within 10 F. The study used the Orion Outer Mold Line model. Five separate factors were identified for study: yaw, pitch, roll, beta angle, and the environmental parameters. Twenty-three external Orion components were selected and their minimum and maximum...
Topics: NASA Technical Reports Server (NTRS), THERMAL ANALYSIS, EXPERIMENT DESIGN, ANGULAR DISTRIBUTION,...
The time-dependent thermo-viscoplastic response of aerospace structures subjected to intense aerothermal loads is predicted using the finite-element method. The finite-element analysis uses the Bodner-Partom unified viscoplastic constitutive relations to determine rate-dependent nonlinear material behavior. The methodology is verified by comparison with experimental data and other numerical results for a uniaxially-loaded bar. The method is then used (1) to predict the structural response of a...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC HEATING, AERODYNAMIC INTERFERENCE, AERODYNAMIC...
The focus of this task was to validate the ADPAC code for heat transfer calculations. To accomplish this goal, the ADPAC code was modified to allow for a Cartesian coordinate system capability and to add boundary conditions to handle spanwise periodicity and transpiration boundaries. The primary validation case was the film cooled C3X vane. The cooling hole modeling included both a porous region and grid in each discrete hold. Predictions for these models as well as smooth wall compared well...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC HEAT TRANSFER, COMPUTATIONAL FLUID DYNAMICS, FILM...
Mainstream Engineering Corporation is developing a gravity-insensitive system that will allow a vapor-compression-cycle heat pump to be used in both microgravity (10(exp -6)g) and lunar (10(exp -6)g) environments. System capacity is 5 kW to 15 kW at design refrigerant operating conditions of 4.44 C and 60 C evaporating and condensing temperatures, respectively. The current program, performed for NASA Johnson Space Center (JSC) and presented in this paper, includes compressor performance...
Topics: NASA Technical Reports Server (NTRS), HEAT PUMPS, MICROGRAVITY, THERMAL ANALYSIS, LUNAR...
Initial transient thermal models have been developed to simulate a heat flux gage calibration process capable of generating high heat flux levels of interest to reciprocating and gas turbine engine industries as well as the aerospace industry. These transient models are based on existing, experimentally validated, steady state models of the cylindrical blackbody calibration system. The steady state models were modified to include insertion of a heat flux gage into the hot zone of the...
Topics: NASA Technical Reports Server (NTRS), CYLINDRICAL BODIES, HEAT FLUX, BLACK BODY RADIATION,...
This paper presents the finite element stress and distortion analysis completed on the Receiver Telescope lens of the Lunar Orbiter Laser Altimeter (LOLA). LOLA is one of six instruments on the Lunar Reconnaissance Orbiter (LRO), scheduled to launch in 2008. LOLA's main objective is to produce a high-resolution global lunar topographic model to aid in safe landings and enhance surface mobility in future exploration missions. The Receiver Telescope captures the laser pulses transmitted through a...
Topics: NASA Technical Reports Server (NTRS), FINITE ELEMENT METHOD, LUNAR ORBITER, RECONNAISSANCE, LENSES,...
Wind tunnels typically have higher free stream turbulence levels than are found in flight. Turbulence intensity was measured to be 0.5 percent in the NASA Lewis Icing Research Tunnel (IRT) with the cloud making sprays off and around 2 percent with cloud making equipment on. Turbulence intensity for flight conditions was found to be too low to make meaningful measurements for smooth air. This difference between free stream and wing tunnel conditions has raised questions as to the validity of...
Topics: NASA Technical Reports Server (NTRS), AIRFOILS, CONVECTIVE HEAT TRANSFER, ICE FORMATION,...
As part of a Constellation session at the 2007 Thermal & Fluids Analysis Workshop (TFAWS), an overview of the Crew Launch Vehicle (CLV), Crew Exploration Vehicle (CEV) and Lunar Lander systems will be given. This presentation provides a general description of the CLV (also known as Ares-I)and Ares-V vehicles portion of the session. The presentation will provide an overview of the thermal requirements, design environments, challenges and thermal modeling examples.
Topics: NASA Technical Reports Server (NTRS), ARES 5 CARGO LAUNCH VEHICLE, SPACECREWS, THERMAL ANALYSIS,...
A heat source such as a magnetic induction/eddy current generator remotely heats a region of a surface of a test structure to a desired depth. For example, the frequency of the heating source can be varied to heat to the desired depth. A thermal sensor senses temperature changes in the heated region as a function of time. A computer compares these sensed temperature changes with calibration standards of a similar sample having known disbond and/or inclusion geography(ies) to analyze the test...
Topics: NASA Technical Reports Server (NTRS), DEFECTS, DEPTH, EDDY CURRENTS, HEAT SOURCES, INCLUSIONS,...
Thermal analysis for the Ares I-X vehicle has involved extensive thermal model integration, since thermal models of vehicle elements came from several different NASA and industry organizations. Many valuable lessons were learned in terms of model integration and validation. Modeling practices such as submodel, analysis group and symbol naming were standardized to facilitate the later model integration. Upfront coordination of coordinate systems, timelines, units, symbols and case scenarios was...
Topics: NASA Technical Reports Server (NTRS), ARES 1 LAUNCH VEHICLE, THERMAL ANALYSIS, TEMPERATURE...
This document describes the development of the Hydrodynamic Power Semiconductor Device Simulator (HPSDS), which solves the quantum mechanical hydrodynamic balance equations for the electrons and holes along with the Poisson equation, for a LW dimensional device. The program will compute the electrostatic potential, electron and hole densities, recombination rate, electron and hole velocities, current densities, electron and hole temperatures, and other quantities of interest as functions of...
Topics: DTIC Archive, Cui, Hong-Liang, STEVENS INST OF TECH HOBOKEN NJ DEPT OF PHYSICS AND ENGINEERING...
Technology refinements to the packaging process, as well as assuring the highest possible yield of serviceable F/S&A systems, are specifically addressed. The primary objective of this research project is to provide a basic physics based understanding of the behavior and performance of Safe and Arm (S & A) systems. The research covers a broad range of activities ranging from basic materials characterization to overall system level models. The research is conducted as a collaborative...
Topics: DTIC Archive, Park, S B, STATE UNIV OF NEW YORK AT BINGHAMTON, *INDIUM, *SAFING AND...
Pressure Differential Scanning Calorimeter (PDSC) is a thermal analytical technique for evaluating oxidation-thermal stability of polymer materials including lubricating greases using the differential heat flow between sample reference thermocouples under various temperatures and pressures. The ASTM D 5483 test method is one of acceptable PDSC techniques to evaluate the grease oxidation stability. In a research effort, a decomposition kinetic model was developed to predict grease high...
Topics: DTIC Archive, Rhee, In-Sik, TACOM RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI, *THERMAL...
The Thermodynamic Ocean Prediction System (TOPS) uses Mellor-Yamada Level II mixing and Ekman dynamics to forecast upper-ocean mixing and wind-drift advection. The U.S. Navy's Fleet Numerical Oceanography Center (FNOC) cycles TOPS with its operational, upper-ocean =, thermal analyses for several regional areas. These include the northern and southern hemispheres, the eastern and western Mediterranean Sea and the Norwegian Sea. The analyses (or nowcasts) provide initial conditions to TOPS. The...
Topics: DTIC Archive, Harding, John H, NAVAL OCEANOGRAPHIC AND ATMOSPHERIC RESEARCH LAB STENNIS SPACE...
The Naval Post Graduate School has obtained software which can be used for the thermal analysis of an electronic component. This software includes two versions, one for steady state analysis and the other for transient analysis. Each version consists of two programs, a model builder and a thermal analyzer. This thesis describes a user friendly, menu driven specific model builder which may be used to rapidly generate a thermal model, containing up to 750 nodes, for a microcircuit die. This model...
Topics: DTIC Archive, Willhelm, Joseph A , Jr, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *THERMAL PROPERTIES,...
Material characterization is essential both for design use and control. Specifically, materials designed for vibration damping and noise suppression precise values of the modulus and loss factor over a wide range of frequency and temperature. Until now, apparatus for making such measurements had very limited frequency and temperature ranges, were of questionable accuracy, and were usually very time consuming to operate. This report presents data as a function of temperature, from the glassy to...
Topics: DTIC Archive, Madigosky, Walter M, NAVAL SURFACE WARFARE CENTER SILVER SPRING MD, *RUBBER,...
The thermal analysis system and tube furnace have been used to conduct initial studies on the conversion of alkoxysiloxy derivatives to metal silicate solid state materials. These results, pertaining titanium, zirconium, and hafnium, are described. Interest in low-temperature chemical routes to ceramic materials is based largely on the potential for generating metastable structures with unusual properties, or on development of improved processing methods. The sol-gel method in particular has...
Topics: DTIC Archive, Tilley, T D, CALIFORNIA UNIV SAN DIEGO LA JOLLA DEPT OF CHEMISTRY, *CONVERSION,...
The Balanced Technology Initiative on Smart Weapons Operability (BTI/SWOE) has a goal to develop a computer simulation capability of the radiant field from the natural environment. This simulation capability would then be used by designers and testers of smart weapons electro-optic sensor systems to study the performance of the systems under anticipated environmental conditions. Vegetation offers a particular challenge to the BTI/SWOE modeling community due to the wide variety in types, shapes,...
Topics: DTIC Archive, Hummel, J R, SPARTA INC LEXINGTON MA, *FIELD TESTS, *COMPUTERIZED SIMULATION,...
Improvements in thermal and physical properties of epoxy resin systems have been demonstrated in the past through the influence of fillers. However, these improvements often come with a significant cost to processability. This paper examines the influence of nanofillers on a multifunctional epoxy resin system in terms of processability and thermal properties. The nanocomposites explored included nanosilica, linear calcium silicate (wollastonite), and polyhedral oligomeric silsesquioxane (POSS)...
Topics: DTIC Archive, Spero, Amy R, AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE, *EPOXY...
The objective of this program was to conduct a study, design and fabricate a cold crucible system for the synthesis and crystal growth of refractory semiconductors and oxides. A theoretical analysis of the cold crucible relating the properties of the material to the electrical characteristics of the cold crucible was completed. The thermal analysis, which includes thermal modeling by means of a computer technique, was also completed. A detailed analysis of the RF power control system necessary...
Topics: DTIC Archive, Wenckus, Joseph F., Cohen, Martin L., Emslie, Alfred G., Menashi, Wilson P., Strong,...
Purified dialkyldichlorosilane monomers were reacted with alkali metals in organic solvent solutions to form linear diorganosilane homopolymers and copolymers. The organosilane polymers were characterized by spectrometric and thermal analysis. Polymer solubilities in organic solvents were determined. Formation of polymer charge transfer complexes were briefly examined. (Author)
Topics: DTIC Archive, Wesson,J P, Williams,T C, UNION CARBIDE CORP TARRYTOWN N Y, *POLYMERS,...
The objective of the program is to perform a design study for a laser-driven, high-intensity pulsed plasma source for X-ray lithography, including a consideration of the effects of such a source on the X-ray mask structures. During this initial quarterly period, work has begun on the design for the CO2 laser driver, as well as on an analysis of the constraints imposed upon the pulsed X-ray source parameters due to thermally-induced stress damage to the mask. The complete design for the CO2...
Topics: DTIC Archive, Ballantyne,A, AVCO EVERETT RESEARCH LAB INC EVERETT MA, *PHOTOLITHOGRAPHY, *X RAY...
The objective of the program is to perform a design study for a laser-driven, high-intensity pulsed plasma source for X-ray lithography, including a consideration of the effects of such a source on the X-ray mask structures. During this initial quarterly period, work has begun on the design for the CO2 laser driver, as well as on an analysis of the constraints imposed upon the pulsed X-ray source parameters due to thermally-induced stress damage to the mask. The complete design for the CO2...
Topics: DTIC Archive, Ballantyne,A, AVCO EVERETT RESEARCH LAB INC EVERETT MA, *PHOTOLITHOGRAPHY, *X RAY...
The energetic plasticizer Shell P722, 2,3-bis(difluoramino)propyl 2, 2-dinitropropyl carbonate, shows excellent stability during prolonged heating. As determined by gas evolution, weight loss, and infrared analysis no significant change occurs after heating for 31 days at 90 C. An improved synthesis of the energetic plasticizer Shell P731, 4,4,4-trinitrobut-1-yl cyanoacetate, is based on the sodium borohydride reduction of trinitrobutyraldehyde to trinitrobutanol (TNBOH) in a water-benzene...
Topics: DTIC Archive, Rocklin, A L, SHELL DEVELOPMENT CO EMERYVILLE CA, *SOLID ROCKET PROPELLANT...
A two-wavelength radiometer and its new computerized data- acquisition/-logging system were installed on the Naval Undersea Center's Oceanographic Research Tower off the coast of San Diego. Data were taken on 14 days during a 6-week period. Meteorological sensors were installed to measure air temperature, dew point, wind speed, bulk-water temperature and net radiative heat flux. A voltage input corresponding to the wind direction was provided and outputs from a 31-element thermistor chain...
Topics: DTIC Archive, Spiess, Fred N, SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA MARINE PHYSICAL LAB,...
Results of classification testing in accordance with US Army Technical Bulletin 700-2 Change, Chapters 3 and 4. Three bulk compositions and two end item munitions were tested. Additional results of all bulk pyrotechnic composition tested to date are included in appendix C of this report.
Topics: DTIC Archive, McIntyre, Fred L, GENERAL ELECTRIC CO BAY SAINT LOUIS MS ENGINEERING AND SCIENCE...
An efficient method has been developed for obtaining a high- resolution temperature distribution of the transient heat conduction inside an arbitrary domain containing any number of anisotropic materials. The method combines an adaptive, unstructured, mesh generation technique and a finite- element analysis program for a multi-material thermal analysis. The technique allows easy generation of fine elements in a high-temperature gradient area and coarse elements in a low-temperature gradient...
Topics: DTIC Archive, Chang, I-Shih, AEROSPACE CORP EL SEGUNDO CA, *FINITE ELEMENT ANALYSIS, *THERMAL...
Unique perfluoro-organic/inorganic oxide hybrid materials have been formulated by merging processes recently developed by us for the solution and melting processing of perfluorosulfonate ionomers (PFSI's) and (2) the production of nanocomposites by the in situ sol-gel reaction for silicon and metal alkoxides within the polar clusters of PFSI's. Our working hypothesis is that the resultant morphology of the inorganic phased is ordered by the nanophase-separated morphology of the PFSI matrix. In...
Topics: DTIC Archive, Mauritz, Kenneth A, UNIVERSITY OF SOUTHERN MISSISSIPPI HATTIESBURG DEPT OF POLYMER...
We report for the first time thermal non-equilibrium (separate electron and gas temperatures) numerical results for a hydrazine arcjet. All viscous flow properties are considered, assuming laminar axisymmetric flow. The model includes anode temperature distribution, and the electrical conductivity is coupled to the flow properties, allowing for a self-consistent current distribution. The numerical solution algorithm employs the compressible form of the PISO algorithm to solve the continuity and...
Topics: DTIC Archive, Krier, Herman, ILLINOIS UNIV AT URBANA DEPT OF MECHANICAL AND INDUSTRIAL ENGINEERING,...
The kinetics of the thermal decomposition of both pure and Mg doped AlH3 have been determined, by using both isothermal constant volume and simultaneous DTA-TGA techniques. Of most importance in these derived parameters is the fact that the activation energy for the thermal decomposition of the Mg doped AlH3 is different from that for the pure AlH3. To help resolve these discrepancies the electrical conductance of these same samples has also been measured as a function of temperature and time....
Topics: DTIC Archive, MARTIN MARIETTA CORP BALTIMORE MD RESEARCH INST FOR ADVANCED STUDIES, *SOLID ROCKET...
The high temperature phase equilibria of the Cr-Si-C and Ni-Si-C ternary systems were investigated by means of melting point, differential thermal analytical, X-ray, and metallographic techniques. Cursory investigations were also made in the Ni-Si and Ni-C binary systems. In the Cr-Si-C system, a ternary D8 sub 8-type phase, which forms two-phase equilibria with most of the other respective binary phases is present. The high temperature phase equilibria include eleven, four-phase reactions of...
Topics: DTIC Archive, Brukl, Charles E, AEROJET-GENERAL CORP SACRAMENTO CA MATERIALS RESEARCH LAB, *CARBON...
Development of probabilistic structural analysis methods for hot structures is a major activity at Lewis Research Center. It consists of five program elements: (1) probabilistic loads; (2) probabilistic finite element analysis; (3) probabilistic material behavior; (4) assessment of reliability and risk; and (5) probabilistic structural performance evaluation. Recent progress includes: (1) quantification of the effects of uncertainties for several variables on high pressure fuel turbopump (HPFT)...
Topics: NASA Technical Reports Server (NTRS), FAILURE ANALYSIS, FINITE ELEMENT METHOD, PROBABILITY THEORY,...
Work done at Case Western Reserve University on the Thermal Mechanical analysis of sprag helicopter clutches is reported. The report is presented in two parts. The first part is a description of a test rig for the measurement of the heat generated by high speed sprag clutch assemblies during cyclic torsional loading. The second part describes a finite element modeling procedure for sliding contact. The test rig provides a cyclic torsional load of 756 inch-pounds at 5000 rpm using a four-square...
Topics: NASA Technical Reports Server (NTRS), CLUTCHES, CONTINUUM MECHANICS, CYCLIC LOADS, HEAT...
Following the Space Shuttle STS-51L disaster on January 28, 1986, a considerable redesign effort was launched on the Solid Rocket Booster. This effort culminated in three instrumented flights, STS-26R, 27R, and 29R, beginning in September of 1989. Aeroheating data were obtained on these flights in the form of pressure, heat flux, and gas temperature probe measurements. These data were analyzed from an ascent and reentry heating point of view. The flight data were verified, compared with...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC HEATING, DESIGN ANALYSIS, FLIGHT INSTRUMENTS,...
The following are discussed: NiH2 battery mission and environment; NiH2 cell heat dissipation; Nodal software; model development general philosophy; NiH2 battery model development; and NiH2 experimental developments.
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, NICKEL HYDROGEN BATTERIES, TEMPERATURE...
In this paper we use a photothermal imaging technique to characterize the damage caused to an imperfectly coated gold-coated Kapton sample exposed to successively increased fluences of atomic oxygen in a laboratory atomic source.
Topics: NASA Technical Reports Server (NTRS), KAPTON (TRADEMARK), METAL COATINGS, MICROSCOPY, OXYGEN ATOMS,...
The investigation of the vibrational disturbances of the Hubble Space Telescope that were discovered soon after deployment in orbit is described in detail. It was found that the disturbances were particularly evident during orbital day-night crossings, and that the magnitude of the disturbances was considerably larger than the design jitter requirement. This paper describes the process by which the vibrations were characterized and isolated to a particular mechanism. The analysis of the flight...
Topics: NASA Technical Reports Server (NTRS), HUBBLE SPACE TELESCOPE, SOLAR ARRAYS, VIBRATION EFFECTS,...
Several lander, probe and rover missions currently under study at the Jet Propulsion Laboratory (JPL) and especially in the Microdevices Laboratory (MDL) Center for Space Microelectronics Technology, focus on utilizing microelectromechanical systems (MEMS) based instruments for science data gathering. These small instruments and NASA's commitment to "faster, better, cheaper" type missions has brought about the need for novel approaches to satisfying mission requirements. Existing...
Topics: NASA Technical Reports Server (NTRS), MICROELECTROMECHANICAL SYSTEMS, MICROELECTRONICS,...
A drop tube-Impulse Atomization technique was used to produce copper droplets. In this method, energy is transferred to a liquid by plunger movement resulting in spherical droplets emanating from orifices. A mathematical model of the evolution of droplet velocity and temperature at various heights for different sized droplets was developed. A two-color pyrometer, DPV-2000, and a shadowgraph were used to measure droplets radiant energy, diameter and velocity. The temperature values from the...
Topics: NASA Technical Reports Server (NTRS), ATOMIZING, COPPER, DROPS (LIQUIDS), MATHEMATICAL MODELS, REAL...
The measurement of Seebeck coefficient and electrical resistivity are critical to the investigation of all thermoelectric systems. Therefore, it stands that the measurement uncertainty must be well understood to report ZT values which are accurate and trustworthy. A detailed uncertainty analysis of the ZEM-3 measurement system has been performed. The uncertainty analysis calculates error in the electrical resistivity measurement as a result of sample geometry tolerance, probe geometry...
Topics: NASA Technical Reports Server (NTRS), THERMOELECTRICITY, SEEBECK EFFECT, APPLICATIONS PROGRAMS...
No abstract available
Topics: NASA Technical Reports Server (NTRS), AEROTHERMODYNAMICS, SPACECRAFT LAUNCHING, ASCENT, AERODYNAMIC...
The Solar Alpha Rotary Joint (SARJ) is a mechanism of the International Space Station (ISS) that orients the solar power generating arrays toward the sun as the ISS orbits our planet. The orientation with the sun must be maintained to fully charge the ISS batteries and maintain all the other ISS electrical systems operating properly. In 2007, just a few months after full deployment, the starboard SARJ developed anomalies that warranted a full investigation including ISS Extravehicular Activity...
Topics: NASA Technical Reports Server (NTRS), MECHANICAL DRIVES, INTERNATIONAL SPACE STATION, SOLAR ARRAYS,...