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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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Thermionic energy converter converts nuclear generated heat directly into high frequency and direct current output. It consists of a potassium plasma cell, a tantalum emitter, and a silver plated copper collector. This conversion process eliminates the steam interface usually required between the atomic heat source and the electrical conversion system.
Isothermal continuous flow calorimeter is designed to test a nickel-cadmium battery under numerous orbital conditions. This sensitive calorimeter collects cell data such as oxygen pressure and rate of heat generation, and calculates changes in enthalpy.
Tables and graphs were compiled for solving nonlinear heat transfer constant area fin problems. The differential equation describing one-dimensional steady-state temperature distribution and heat flow under three modes of heat transfer with heat generation was investigated.
Lubricating mechanism, cage design, and heat generation of ball bearings for liquid hydrogen turbopumps, and design factors of contact seals for liquid fluorine pumps
Improved cutting fluid completely controls the heat generated from machining operations, thus providing longer tool life. Fluid is especially useful in the working of plastics and replaces less efficient contaminating oils.
Voltage regulator provides improved voltage-regulating system in which power dissipation and consequent heat generation are minimized. Each power source section is controlled sequentially so that only one operates in a linear range at a time.
Switching circuit utilizing silicon controlled rectifier reduces input power requirements normally associated with testing power semiconductors in an operational type mode. Circuit alleviates problems of inaccessibility, lack of large amounts of power, physical size of power resistors, wiring, and heat generation.
Module utilizes static water-feed electrolysis system and air-cooled fins to remove heat generated by cell inefficiencies. Module generates 0.15 pounds of oxygen and 0.0188 pounds of hydrogen at current density of 100 amps per square foot. Generator operates in aircraft, spacecraft, or submarine cabins.
Units are used for repairing and assembling stainless steel tubing. Heat generated by chemical reaction is used to melt brazing alloy and bonded area is not contaminated by the reactants or by-products of the reaction.
Existence and extendability of continuous eigenvector branches and application of nonlinear programming algorithms to nonlinear heat generation and rotating string problems
Living human tissue thermal behavior analytical modeling including internal heat generation and blood flow effects
Thermal behavior simulation of cooling biological system, describing heat generation and transfer at normothermic to hibernating body temperatures with mathematical model
The auxiliary power unit (APU) for the space shuttle is required to provide hydraulic and electrical power on board the booster and orbiter vehicles. Five systems and their associated components, which utilize hot gas turbines to supply horsepower at gearbox output pads, were studied. Hydrogen-oxygen and storable propellants were considered for the hot gas supply. All APU's were required to be self-contained with respect to dissipating internally generated heat. These five systems were evaluated relative to a consistent criteria. The system supplied with high pressure gaseous hydrogen and oxygen was recommended as the best approach. It included a two-stage pressure-compounded partial-admission turbine, a propellant conditioning system with recuperation, a control system, and a gearbox. The gearbox output used was 240 hp. At the close of the study a 400 hp level was considered more appropriate for meeting the prime shuttle vehicle needs, and an in-depth analysis of the system at the 400 hp output level was recommended.
A test program was carried out to demonstrate an igniter motor initiation system utilizing the bimetallic material Pyrofuze for a solid propellant rocket with controlled low rate of thrust buildup. The program consisted of a series of vacuum ignition tests using a slab burning window motor that simulated the principal initial ballistic parameters of the full scale igniter motor. A Pyrofuze/pyrotechnic igniter system was demonstrated that uses a relatively low electrical current level for initiation and that eliminates the necessity of a pyrotechnic squib, with its accompanying accidental firing hazards and the typical basket of pyrotechnic pellets. The Pyrofuze ignition system does require an initial constraining of the igniter motor nozzle flow, and at the low initiating electrical current level the ignition delay time of this system was found to be quite sensitive to factors affecting local heat generation or loss rates.
The auxiliary power unit (APU) for the space shuttle is required to provide hydraulic and electrical power on board the booster and orbiter vehicles. Five systems and their associated components, which utilize hot gas turbines to supply horsepower at gearbox output pads, were studied. Hydrogen-oxygen and storable propellants were considered for the hot gas supply. All APU's were required to be self contained with respect to dissipating internally generated heat. These five systems were evaluated relative to a consistent criteria. The system supplied with high pressure gaseous hydrogen and oxygen was recommended as the best approach. It included a two-stage pressure-compounded partial-admission turbine, a propellant conditioning system with recuperation, a control system, and a gearbox. The gearbox output used was 240 HP. At the close of the study a 400 HP level was considered more appropriate for meeting the prime shuttle vehicle needs, and an in-depth analysis of the system at the 400 HP output level was recommended.
An analytical study is presented which shows the effects of large energy release and the concurrent high acceleration of inner stream fluid on the coaxial flow field in a gas core reactor. The governing equations include the assumptions of only radial radiative transport of energy represented as an energy diffusion term in the Euler equations. The method of integral relations is used to obtain the numerical solution. Results show that the rapidly accelerating, heat generating inner stream actually shrinks in radius as it expands axially.
Lunar heat-flow calculations are carried out for a model moon in which (1) near-surface initial temperatures are very high (as the occurrence of a surface anorthositic layer seems to require), and (2) heat-generating radionuclides are transported upward when melting occurs. Near-surface regions are found to cool and then experience a resurgence of high temperature, as radionuclide-rich magmas from the lunar interior accumulate near the surface. This peaking of near-surface temperature can be brought into correspondence with the episode of vulcanism that gave rise to the basalts represented in the Apollo samples, if we assume relatively high lunar temperatures in early times (due to high initial temperatures, or a high content of radioactive elements, or both).
Planetary quarantine analyses performed for recent unmanned Mars and Venus missions assumed that the probability of contamination by a spacecraft given accidental impact was equivalent to one. However, in the case of the gaseous outer planets, the heat generated during the inadvertent entry of a spacecraft into the planetary atmosphere might be sufficient to cause significant microbial burden reduction. This could affect navigation strategy by reducing the necessity for biasing the aim point away from the planets. An effort has been underway to develop the tools necessary to predict temperature histories for a typical spacecraft during inadvertent entry. In order that the results have general applicability, parametric analyses were performed. The thermal response of the spacecraft components and debris resulting from disintegration was determined. The temperature histories of small particles and composite materials, such as thermal blankets and an antenna, were given special attention. Guidelines are given to indicate the types of components and debris most likely to contain viable organisms, which could contaminate the lower layers of the Jovian atmosphere (approximately one atmosphere of pressure).