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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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Program uses combination of procedures to determine eigenfunction solutions of discrete damped structures, including spinning ones, while fully exploiting banded configuration of associated matrices.
Apollo Program experience in the processing of scientific data from the Apollo lunar surface experiments package, in which computers and associated hardware and software were used, is summarized. The facility developed for the preprocessing of the lunar science data is described, as are several computer facilities and programs used by the Principal Investigators. The handling, processing, and analyzing of lunar science data and the interface with the Principal Investigators are discussed. Pertinent problems that arose in the development of the data processing schemes are discussed so that future programs may benefit from the solutions to the problems. The evolution of the data processing techniques for lunar science data related to recommendations for future programs of this type.
Computer program based on heave/pitch analysis simulates dynamic behavior during landing impact and taxi over irregular runway. Program can be adapted to run on any computer with FORTRAN compiler.
Computer program performs transient thermal analysis of any 2-node to 200-node-thermal network, which transports heat by fluid flow convection. Program can be modified to add conduction along tubes and radiation.
Digital systems which deal with functions outside the aircraft in commercial aviation are discussed with attention to navigation and communication. New systems of air traffic control (ATC) are described, including time division multiple access (TDMA) to ground-based ATC units and to the Navstar/GPS (global positioning system). Such innovations are expected to come on-line before the mid-1980s, and greatly increase air safety, while at the same time making a pilot's work easier.
A program is underway to design, develop, fabricate, and qualify large high-load forward and aft separation bolts for the Space Shuttle; the bolts will serve as attachment between two solid rocket boosters and the external tank. This paper reviews bolt development, with emphasis on the scaling of components, the use of high strength maraging steel for the internal components, and the use of lead as a hydraulic fluid.
Laser systems deployed in satellite tracking were upgraded to accuracy levels where biases from systematic unmodelled effects constitute the basic factor that prohibits extraction of the full amount of information contained in the observations. Taking into consideration that the quality of the instrument advances at a faster pace compared to the understanding and modeling of the physical processes involved, one can foresee that in the near future when all lasers are replaced with third generation ones the limiting factor for the estimated accuracies will be the aforementioned biases. Therefore, for the reduction of the observations, methods should be deployed in such a way that the effect of the biases will be kept well below the noise level. Such a method was proposed and studied. This method consists of using the observed part of the satellite pass and converting the laser ranges into range differences in hopes that they will be less affected by biases in the orbital models, the reference system, and the observations themselves.
Program provides batch and device queueing facilities for various computers networked in UNIX environment. Allows network manager to allocate and track resources across network without requiring user to specifically log in on remote target machines.
Program aids in structural design of wide range of objects, from high-impact printer parts to turbine engine blades, and fully validated. Since source code included, NASTRAN modified or enhanced for new applications.
Current programs addressed in aeroassist flight experiment are: (1) evaluation of thermal performance of advanced rigid and flexible insulations and reflective coating; (2) investigation of lighter than baseline materials; (3) investigation of rigid insulations which perform well; (4) study of flexible insulations which require ceramic coating; and (5) study of reflective coating effective at greater than 15 percent. In National Aerospace Plane (NASP), the programs addressed are: (1) high and low temperature insulations; and (2) attachment/standoff methodology critical which affects thermal performance.
The program goal is to develop a computerized life prediction model capable of identifying present aging progress and predicting end of life for aircraft wiring. A summary is given in viewgraph format of progress made on phase 1 objectives, which were to identify critical aircraft wiring problems; relate most common failures identified to the wire mechanism causing the failure; assess wiring requirments, materials, and stress environment for fighter aircraft; and demonstrate the feasibility of a time-temperature-environment model.
A program was conducted to determine if a state of the art micro-machined silicon solid state flow sensor could be used to replace the existing space shuttle orbiter flow sensors. The rather aggressive goal was to obtain a new sensor which would also be a multi-gas sensor and operate over a much wider flow range and with a higher degree of accuracy than the existing sensors. Two types of sensors were tested. The first type was a venturi throat design and the second was a bypass design. The accuracy of venturi design was found to be marginally acceptable. The bypass sensor was much better although it still did not fully reach the accuracy goal. Two main problems were identified which would require further work.
The U.S. Space Exploration Policy has established a vision for human exploration of the moon and Mars. One option for power for future outposts on the lunar and Martian surfaces is a nuclear reactor coupled with a free-piston Stirling convertor at a power level of 30-40 kWe. A 25 kW convertor was developed in the 1990s under the SP-100 program. This system consisted of two 12.5 kWe engines connected at their hot ends and mounted in tandem to cancel vibration. Recently, NASA began a new project with Auburn University to develop a 5 kWe, single convertor for use in such a possible lunar power system. Goals of this development program include a specific power in excess of 140 We/kg at the convertor level, lifetime in excess of five years and a control system that will safely manage the convertors in case of an emergency. Foster-Miller, Inc. is developing the 5 kWe Stirling Convertor Assembly. The characteristics of the design along with progress in developing the system will be described.
- The Natural Environments (NE) Branch is within the MSFC Engineering Directorate’s Spacecraft and Vehicle System (S&VS) Department - S&VS plans, performs and directs the technical Design, Analysis, Test, Evaluation, Verification, Integration, and Applied Research and Development of future Spacecraft and Launch Vehicle Systems - Current programs we support - Space Launch System, Human Landing System, Mars Ascent Vehicle, Orion, Gateway - NE maintains expertise in terrestrial, space, and planetary natural environments definition, characterization, and analysis - Responsibility to disseminate this expertise to Agency programs and projects in support of environment definition, requirements development, vehicle development, operations, and sustaining engineering through program’s life cycle - Branch has two teams; Terrestrial and Planetary Environments (T&PE) and Space Environments (SE) - T&PE has extensive expertise characterizing terrestrial surface and atmospheric (aloft) environments - Winds, temperature, humidity, pressure, lightning, density, precipitation, radiant energy, aerosols, sea state, sea surface temperature - Maintains climatological databases for engineering analyses
The Automated Requirements Management System, which is being developed to support traceability and documentation of Space Station Freedom requirements, is described. The objectives of requirements management are validation and verification. Other benefits include comprehensive analytical capabilities, commonality and timeliness of requirements information availability across the program, and the reduction of information duplication and overlap.
This document describes the theoretical methods used in the rotorcraft noise prediction system (ROTONET), which is a part of the NASA Aircraft Noise Prediction Program (ANOPP). The ANOPP code consists of an executive, database manager, and prediction modules for jet engine, propeller, and rotor noise. The ROTONET subsystem contains modules for the prediction of rotor airloads and performance with momentum theory and prescribed wake aerodynamics, rotor tone noise with compact chordwise and full-surface solutions to the Ffowcs-Williams-Hawkings equations, semiempirical airfoil broadband noise, and turbulence ingestion broadband noise. Flight dynamics, atmosphere propagation, and noise metric calculations are covered in NASA TM-83199, Parts 1, 2, and 3.
As part of the NASA Integrated Systems Research Program, Environmentally Responsible Aviation Project, NASA GRC and GE Aviation have partnered to investigate the technology barriers associated with improved fuel economy of large gas turbine engines. Crucial to improving fuel economy is the increase in Pressure Ratio (PR) of the core compressor. General Electric is in the process of defining new advanced technology engine concepts and related engine architectures for both commercial and military subsonic and supersonic flight applications. These new concepts and architectures offer the potential of providing substantial improvements in mission fuel burn, emissions, and noise levels relative to SOTA engines and support the needs and goals of future Air force, Navy, and NASA aircraft systems. A key aspect of many of these new engine concepts is an ultra high pressure ratio core compressor. Current SOTA engines such as the GENx utilize a 23:1 class pressure ratio core compressor to achieve an overall pressure ratio in the 50:1 class. Future engines with overall pressure ratios in the 70– 80:1 class will need core compressors with pressure ratios in the 30:1 class. These single spool, ultra high pressure ratio compressors will have inherent challenges. The goal of this work is to provide a dedicated component test vehicle to study the very challenging compressor front stage performance and operability issues that arise in these aggressive machines. With a view to providing highly detailed aerodynamic data that will provide, subject to the rights restrictions for test data afforded under NASA Contract NNC10BA06B/NNC10TA64T, an industry standard data set for CFD validation.
The NASA Controlled Ecological Life Support System (CELSS) program was initiated with the premise that NASA's goal would eventually include extended duration missions with sizable crews requiring capabilities beyond the ability of conventional life support technology. Currently, as mission duration and crew size increase, the mass and volume required for consumable life support supplies also increase linearly. Under these circumstances the logistics arrangements and associated costs for life support resupply will adversely affect the ability of NASA to conduct long duration missions. A solution to the problem is to develop technology for the recycling of life support supplies from wastes. The CELSS concept is based upon the integration of biological and physico-chemical processes to construct a system which will produce food, potable water, and a breathable atmosphere from metabolic and other wastes, in a stable and reliable manner. A central feature of a CELSS is the use of green plant photosynthesis to produce food, with the resulting production of oxygen and potable water, and the removal of carbon dioxide.