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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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The results of the verification testing sequence V-2 performed on the space shuttle solid rocket booster thrust vector control subsystem are presented. A detailed history of the hot firings plus additional discussion of the auxiliary power unit and the hydraulic component performance is presented. The test objectives, data, and conclusions are included.
The results of the orbiter hardware/software interaction analysis for the AFT reaction control system are presented. The interaction between hardware failure modes and software are examined in order to identify associated issues and risks. All orbiter subsystems and interfacing program elements which interact with the orbiter computer flight software are analyzed. The failure modes identified in the subsystem/element failure mode and effects analysis are discussed.
The orbiter subsystems and interfacing program elements which interact with the orbiter computer flight software are analyzed. The failure modes identified in the subsystem/element failure mode and effects analysis are examined. Potential interaction with the software is examined through an evaluation of the software requirements. The analysis is restricted to flight software requirements and excludes utility/checkout software. The results of the hardware/software interaction analysis for the forward reaction control system are presented.
The test procedures and results in qualifying the Honeywell single family residence solar collector subsystem are presented. Testing was done in the following areas: pressure, service loads, hail, solar degradation, pollutants, thermal degradation, and outgassing.
The performance of Bosch hardware at the subsystem level (up to five-person capacity) in terms of five operating parameters was investigated. The five parameters were: (1) reactor temperature, (2) recycle loop mass flow rate, (3) recycle loop gas composition (percent hydrogen), (4) recycle loop dew point and (5) catalyst density. Experiments were designed and conducted in which the five operating parameters were varied and Bosch performance recorded. A total of 12 carbon collection cartridges provided over approximately 250 hours of operating time. Generally, one cartridge was used for each parameter that was varied. The Bosch hardware was found to perform reliably and reproducibly. No startup, reaction initiation or carbon containment problems were observed. Optimum performance points/ranges were identified for the five parameters investigated. The performance curves agreed with theoretical projections.
Measured characteristics of the spectrum of typical converters and the distribution of radiated Radio Frequency (RF) energy from the terminals (transmitting antenna and rectenna) of a beamed microwave power subsystem are presented for small transmitting and receiving S-band (2.45 GHz) subarrays. Noise and harmonic levels of tube and solid-state RF power amplifiers are shown. The RF patterns and envelope of a 64 element slotted waveguide antenna are given for the fundamental frequency and harmonics through the fifth. Reflected fundamental and harmonic patterns through the fourth for a 42 element rectenna subarray are presented for various dc load and illumination conditions. Bandwidth measurements for the waveguide antenna and rectenna are shown.
The scheduling algorithm for mission planning and logistics evaluation (SAMPLE) is presented. Two major subsystems are included: The mission payloads program; and the set covering program. Formats and parameter definitions for the payload data set (payload model), feasible combination file, and traffic model are documented.
The digital recording acquisition subsystem (DRAS) is a wideband digital recording system that can accommodate data sample rates from 0.125 to 8 MHz in binary increments. The implementation of the DRAS for radio interferometry applications in support of the Crustal Dynamics Project is described. The functional and performance characteristics of the equipment and the key aspects of the implementation plan are discussed.
Using a mathematical model, requirements for each of the nonavionic subsystems that interface with the shuttle avionics system are given.
Subsystem performance analysis required in flight design to assess the capability of the environmental control and life support system (ECLSS) to support the flight requirements and define operational procedures under contingency flight conditions is described. Current ECLSS modeling techniques are limited in the variety of configurations and they employ batch mode computer programs execution methods. Improvements in the variety of configurations that are modeled and a reduction in effort required for modeling and analysis is accomplished by developing a modular computer program which operates interactively.
A user guide for a library of interactive computer routines used to develop performance analysis models of specific environmental control and life support subsystems is presented.
This paper describes the use, operation, and preliminary thermal modeling of a Portable Oxygen Subsystem (POS). The POS is a partial rebreather which is being developed for Shuttle Orbiter support. Normally used as a pre-breather for denitrogenization prior to EVA, this semi-closed, breath powered breathing system can also be used for emergencies in the event of a contaminated or oxygen-deficient cabin atmosphere, to support an emergency transfer between vehicles, or as a clean oxygen supply in the event of a contaminated ambient atmosphere in the vicinity of the Orbiter after landing.
Nickel-cadmium batteries of 20 and 50 ampere-hour (AH) capacity have been developed and qualified. These batteries provide an energy storage capability of 40 to 150 AH for the Modular Power Subsystem, which is the power source for NASA's Multimission Modular Spacecraft. Battery fabrication is rigidly controlled to assure uniform performance from battery to battery. A unique feature of the battery design is that cells from various manufacturers can be used for battery assembly without modification. Both 20 and 50-AH batteries have been delivered, and an MPS module with three 20-AH batteries is currently operating satisfactorily in low earth orbit. Design characteristics and performance of the batteries are described.
Integrated subsystem level testing of the systems within the orbiter active thermal chamber capable of simulating ground, orbital, and entry temperature and pressure profiles. The test article was in a closed loop configuration that included flight type and functionally simulated protions of all ATCS components for collecting, transporting, and rejecting orbiter waste heat. Specially designed independently operating equipment simulated the transient thermal input from the cabin, payload, fuel cells, freon cold plates, hydraulic system, and space environment. Test team members using data, controls, and procedures available to a flight crew controlled the operation of the ATCS. The ATCS performance met or exceeded all thermal and operational requirements for planned and contingency mission support.
The functions of the JOB BUILDER remote batch processing subsystem are described. Instructions are given for using it as a component of a display system developed by personnel of the System Programming Laboratory, Institute of Space Research, USSR Academy of Sciences.
The effects on life cycle costs (LCC) of major design and performance technology parameters for multi kW LEO and GEO energy storage subsystems using NiCd and NiH2 batteries and fuel cell/electrolysis cell devices were examined. Design, performance and LCC dynamic models are developed based on mission and system/subsystem requirements and existing or derived physical and cost data relationships. The models define baseline designs and costs. The major design and performance parameters are each varied to determine their influence on LCC around the baseline values.
The effects on life cycle costs (LCC) of major design and performance technology parameters for multi kW LEO and GEO energy storage subsystems using NiCd and NiH2 batteries and fuel cell/electrolysis cell devices were examined. Design, performance and LCC dynamic models are developed based on mission and system/subsystem requirements and existing or derived physical and cost data relationships. The models are exercised to define baseline designs and costs. Then the major design and performance parameters are each varied to determine their influence on LCC around the baseline values.
An environmental control subsystem (ECS) in the passenger compartment of electric and hybrid vehicles is studied. Various methods of obtaining the desired temperature control for the battery pack is also studied. The functional requirements of ECS equipment is defined. Following categorization by methodology, technology availability and risk, all viable ECS concepts are evaluated. Each is assessed independently for benefits versus risk, as well as for its feasibility to short, intermediate and long term product development. Selection of the preferred concept is made against these requirements, as well as the study's major goal of providing safe, highly efficient and thermally confortable ECS equipment.