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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Power from the Space Shuttle

The use of the Space Shuttle to provide avionics and electrical power accommodations to a large dedicated payload and/or to multiple smaller payloads throughout the flight is studied. The payload equipment can be mounted in the Shuttle Orbiter aft flight deck and middeck portions of the crew cabins and in the Orbiter cargo bay. The Orbiter provides avionics services to the following major payload classes: the single-section payload, the small payload, the middeck payload, and the Get-Away Special payload.

Speier, William M.↗
NASA NTRS1972

The solid polymer electrolyte fuel cell for the Space Shuttle Orbiter.

Recent developments in the General Electric solid polymer electrolyte fuel cell have demonstrated the capability of 2000 hours of maintenance-free life and the potential for 5000 to 10,000 hours of useful life with invariant performance. Hardware developments for a 5 kW fuel cell module directed toward NASA's Space Shuttle Orbiter application have demonstrated the capability of operation on propulsion-grade reactants, operation with simple stop/start procedures, and with a specific weight of 25 lb/kW for a complete module.

Chapman, L. E.↗
NASA NTRS2003

Forced Forward Smoldering Experiments Aboard The Space Shuttle

Smoldering is a basic combustion problem that presents a fire risk because it is initiated at low temperatures and because the reaction can propagate slowly in the material interior and go undetected for long periods of time. It yields a higher conversion of fuel to toxic compounds than does flaming, and may undergo a transition to flaming. To date there have been a few minor incidents of overheated and charred cables and electrical components reported on Space Shuttle flights. With the establishment of the International Space Station, and the planning of a potential manned mission to Mars, there has been an increased interest in the study of smoldering in microgravity. The Microgravity Smoldering Combustion (MSC) experiment is part of a study of the smolder characteristics of porous combustible materials in a spacecraft environment. The aim of the experiment is to provide a better fundamental understanding of the controlling mechanisms of smoldering combustion under normal- and microgravity conditions. This in turn will aid in the prevention and control of smolder originated fires, both on earth and in spacecrafts. The microgravity smoldering experiments have to be conducted in a space-based facility because smoldering is a very slow process and consequently its study in a microgravity environment requires extended periods of time. The microgravity experiments reported here were conducted aboard the Space Shuttle. The most recent tests were conducted during the STS-105 and STS-108 missions. The results of the forward smolder experiments from these flights are reported here. In forward smolder, the reaction front propagates in the same direction as the oxidizer flow. The heat released by the heterogeneous oxidation reaction is transferred ahead of the reaction heating the unreacted fuel. The resulting increase of the virgin fuel temperature leads to the onset of the smolder reaction, and propagates through the fuel. The MSC data are compared with normal gravity data to determine the effect of gravity on smolder.

Fernandez-Pello, A. C.↗
NASA NTRS1985

Astronaut hazard during free-flight polar EVA

Extravehicular Activity (EVA) during Shuttle flights planned for the late 1980's includes several factors which together may constitute an astronaut hazard. Free-flight EVA is planned whereas prior United States Earth orbit EVA has used umbilical tethers carrying communications, coolant, and oxygen. EVA associated with missions like LANDSAT Retrieval will be in orbits through the auroral oval where charging of spacecraft may occur. The astronaut performing free flight EVA constitutes an independent spacecraft. The astronaut and the Shuttle make up a system of electrically isolated spacecraft with a wide disparity in size. Unique situations, such as the astronaut being in the wake of the Shuttle while traversing an auroral disturbance, could result in significant astronaut and Shuttle charging. Charging and subsequent arc discharge are important because they have been associated with operating upsets and even satellite failure at geosynchronous orbit. Spacecraft charging theory and experiments are examined to evaluate charging for Shuttle size spacecraft in the polar ionosphere.

Hall, W. N.↗
NASA NTRS1985

The investigation of tethered satellite system dynamics

Progress in tethered satellite system dynamics research is reported. A retrieval rate control law with no angular feedback to investigate the system's dynamic response was studied. The initial conditions for the computer code which simulates the satellite's rotational dynamics were extended to a generic orbit. The model of the satellite thrusters was modified to simulate a pulsed thrust, by making the SKYHOOK integrator suitable for dealing with delta functions without loosing computational efficiency. Tether breaks were simulated with the high resolution computer code SLACK3. Shuttle's maneuvers were tested. The electric potential around a severed conductive tether with insulator, in the case of a tether breakage at 20 km from the Shuttle, was computed. The electrodynamic hazards due to the breakage of the TSS electrodynamic tether in a plasma are evaluated.

Lorenzini, E.↗
NASA NTRS1997

Lightning Threat Analysis for the Space Shuttle Launch Pad and the Payload Changeout Room Using Finite Difference Methods

This report describes finite difference computer calculations for the Space Shuttle Launch Pad which predict lightning induced electric currents and electric and magnetic fields caused by a lightning strike to the Lightning Protection System caternary wire. Description of possible lightning threats to Shuttle Payload components together with specifications for protection of these components, result from the calculation of lightning induced electric and magnetic fields inside and outside the during a lightning event. These fields also induce currents and voltages on cables and circuits which may be connected to, or a part of, shuttle payload components. These currents and voltages are also calculated. These threat levels are intended as a guide for designers of payload equipment to specify any shielding and/or lightning protection mitigation which may be required for payload components which are in the process of preparation or being transferred into the Shuttle Orbiter.

Collier, Richard S.↗
NASA NTRS1999

Observations from the Microgravity Smoldering Combustion (MSC) Ultrasound Imaging System (UIS)

The Microgravity Smoldering Combustion (MSC) experiment is a study of the smolder characteristics of porous combustible materials in a microgravity environment. The objective of the study is to provide a better understanding of the controlling mechanisms of smolder, both in microgravity and normal earth gravity. Experiments have been conducted aboard the NASA Space Shuttle in the GAS-CAN, an apparatus requiring completely remote operation. Future GAS-CAN experiments will utilize an ultrasound imaging system (UIS). Thermocouples are currently used to measure temperature and reaction front velocities, but a less intrusive method is desirable, as smolder is affected by heat transfer along the thermocouple. It is expected that the UIS will eventually replace the existing array of thermocouples as a non-intrusive technique without compromising data acquisition. Smoldering is defined as a non-flaming, self-sustaining, propagating, exothermic, surface reaction, deriving its principal heat from heterogeneous oxidation of the fuel. Smolder of cable insulation is of particular concern in the space program; to date there have been a few minor incidents of overheated and charred cables and electrical components reported on Space Shuttle flights. Recently, the establishment of the International Space Station and other space facilities has increased interest in the study of smoldering in microgravity because of the need to preempt the possibility, and/or to minimize the effect of a smolder initiated fire during the operation of these facilities. The ignition and propagation of smolder are examined using both thermocouples and the UIS. The UIS has been implemented into the MSC flight hardware. The system provides information about local permeability variations within a smoldering sample, which can, in turn, be interpreted to track the propagation of the smolder reaction. The method utilizes the observation that transmission of an ultrasonic signal through a porous material increases with increasing permeability. Since a propagating smolder reaction leaves behind a char that is higher in permeability than the original (unburnt) material, ultrasonic transmission can be employed to monitor the progress of the primary reaction front, char evolution (i.e. material left by the smolder reaction), pyrolysis, and condensation fronts.

Walther, D.C.↗
NASA NTRS1975

Experiment definition studies for AMPS Spacelab

The electrical charging of the space shuttle orbiter is discussed in relation to the AMPS Spacelab payload along with an operations research technique for the selection of AMPS Spacelab experiments. Experiments proposed for AMPS include: hydromagnetic wave experiments; bistatic sounder of AMPS wake; and an artificial meteor gun. Experiment objectives and instrument functions are given for all experiments.

Liemohn, H.↗
NASA NTRS1977

Study of an astronomical extreme ultraviolet rocket spectrometer for use on shuttle missions

The adaptation of an extreme ultraviolet astronomy rocket payload for flight on the shuttle was studied. A sample payload for determining integration and flight procedures for experiments which may typically be flown on shuttle missions was provided. The electrical, mechanical, thermal, and operational interface requirements between the payload and the orbiter were examined. Of particular concern was establishing a baseline payload accommodation which utilizes proven common hardware for electrical, data, command, and possibly real time monitoring functions. The instrument integration and checkout procedures necessary to assure satisfactory in-orbit instrument performance were defined and those procedures which can be implemented in such a way as to minimize their impact on orbiter integration schedules were identified.

Bowyer, C. S.↗
NASA NTRS1978

A programmable power processor for a 25 kW power module

The paper presents the concept and major design problems of a programmable power processor for the 25 kW electrical power system for the Shuttle Orbiter. The load will be handled by three parallel power stages operated in phase sequence with each power transistor having its own commutating diode and filter inductor. The power stages will be run at a fixed frequency of 10 kHz with the 'on'-time variable up to 100%. The input filter bank in the breadboard programmable power processor is planned to be a series-parallel combination of tantalum cased tantalum wet-slug capacitors.

Kapustka, R. E.↗
NASA NTRS1982

NASA solar array flight experiment

The NASA large flexible solar array space shuttle flight experiment is described. The 32 x 4 m wing is deployed from the shuttle bay, and experiments in electrical output, multiple deployment, and structural dynamics are planned. Both 2 x 4 cm and 5.9 x 5.9 cm cell assemblies on the array blanket are evaluated. Safety/hazards provisions are described, including emergency jettison provisions. Ground testing and hardware fabrication are summarized.

Turner, G.↗
NASA NTRS2015

Shock Absorbers Save Structures and Lives during Earthquakes

With NASA funding, North Tonawanda, New York-based Taylor Devices Inc. developed fluidic shock absorbers to safely remove the fuel and electrical connectors from the space shuttles during launch. The company is now employing the technology as seismic dampers to protect structures from earthquakes. To date, 550 buildings and bridges have the dampers, and not a single one has suffered damage in the wake of an earthquake.

Source record↗
NASA NTRS2000

Electrical Auxiliary Power Unit (EAPU) Corona Design Guideline

This document is the result of a collaborative effort between NASA's Johnson Space Center, Marshall Space Flight Center, Glenn Research Center, and the United States Air Force Research Laboratory at Wright Patterson AFB in support of the Space Shuttle Orbiter Upgrades Program, specifically the Electric Auxiliary Power Unit Program. This document is intended as a guideline for design applications for corona and partial discharge avoidance and is not a requirements specification instrument.

Hall, David K.↗
NASA NTRS1977

Transportation concepts for space industrialization

Space shuttle and heavy lift launch vehicle concepts are described with attention to transportation cost trends. Chemical (LOX/LH2), nuclear, and electric propulsion systems are considered. Suggested space shuttle projects include the support of manned geosynchronous missions and the transfer of bulk cargo and large-delicate space structures from fabrication/assembly orbits to their operational locations. It is thought that development of the space shuttle will stimulate interest in space industrialization.

Murphy, J. T.↗
NASA NTRS1975

Nuclear energy waste-space transportation and removal

A method for utilizing the decay heat of actinide wastes to power an electric thrust vehicle is proposed. The vehicle, launched by shuttle to earth orbit and to earth escape by a tug, obtains electrical power from the actinide waste heat by thermionic converters. The heavy gamma ray and neutron shielding which is necessary as a safety feature is removed in orbit and returned to earth for reuse. The problems associated with safety are dealt with in depth. A method for eliminating fission wastes via chemical propulsion is briefly discussed.

Burns, R. E.↗
NASA NTRS2004

Electromagnetic Compatibility for the Space Shuttle

This slide presentation reviews the Space Shuttle electromagnetic compatibility (EMC). It includes an overview of the design of the shuttle with the areas that are of concern for the electromagnetic compatibility. It includes discussion of classical electromagnetic interference (EMI) and the work performed to control the electromagnetic interference. Another area of interest is electrostatic charging and the threat of electrostatic discharge and the attempts to reduce damage to the Shuttle from these possible hazards. The issue of electrical bonding is als reviewed. Lastly the presentation reviews the work performed to protect the shuttle from lightning, both in flight and on the ground.

Scully, Robert C.↗
NASA NTRS1978

Atmospheric electrification

Research areas of atmospheric electricity that could be explored from the shuttle or the tethered satellite are discussed. Emphasis is placed on atmospheric current flow and telluric currents. A model depicting the atmospheric electric global circuit is presented.

Kasemir, H. W.↗
NASA NTRS1972

Status of shuttle fuel cell technology program.

The hydrogen-oxygen fuel cell has been proved as an efficient and reliable electrical power supply for NASA manned-space-flight vehicles. It has thus ensured a role in the Space Shuttle Program as the primary electrical power supply for the Orbiter vehicle. The advanced fuel cell technology programs conducted under the management of the NASA Manned Spacecraft Center over the past two years have resulted in a high level of technical readiness in fuel cell power generation to support shuttle mission requirements. These programs have taken advantage of technological developments that have occurred since the designs were completed for the Gemini and Apollo fuel cells.

Rice, W. E.↗