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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 development of the module concepts are reviewed, and a number of functional elements are listed. Other areas examined include some of the following; (1) mission operations; (2) environmental control and life support subsystems concepts; (3) thermal heat rejection; (4) space radiation effect analysis; and (5) satellite power system test requirements.
The equations for processing ground tracking data during a space shuttle ascent or entry, or any nonfree flight phase of a shuttle mission are given. The resulting computer program processes data from up to three stations simultaneously: C-band station number 1; C-band station number 2; and an S-band station. The C-band data consists of range, azimuth, and elevation angle measurements. The S-band data consists of range, two angles, and integrated Doppler data in the form of cycle counts. A nineteen element state vector is used in Kalman filter to process the measurements. The acceleration components of the shuttle are taken to be independent exponentially-correlated random variables. Nine elements of the state vector are the measurement bias errors associated with range and two angles for each tracking station. The biases are all modeled as exponentially-correlated random variables with a typical time constant of 108 seconds. All time constants are taken to be the same for all nine state variables. This simplifies the logic in propagating the state error covariance matrix ahead in time.
The distortion and degradation of the informational content of satellite sensed data by scene generation and atmospheric propagation are discussed. A method is described for obtaining a system point spread function representing the fractional radiance poisoning each pixel gives and receives. The sensor data output is then reprocessed or restored. The degree of restoration is signal to noise dependent. A technique is given for approximating the impact of the atmosphere on the propagation of scene radiance.
A brief description of recommended supporting research and technology items resulting from the space station analysis study is provided. Descriptions include the title; the status with respect to the state of the art; the justification; the technical plan including objectives and technical approach; resource requirements categorized by manpower, specialized facilities, and funding in 1977 dollars; and also the target schedule. The goal is to provide high confidence in the solutions for the various functional system development problems, and to do so within a time period compatible with the overall evolutionary space construction base schedule.
Cost estimates for the space station systems analysis were recorded. Space construction base costs and characteristics were cited as well as mission hardware costs and characteristics. Also delineated were cost ground rules, the program schedule, and a detail cost estimate and funding distribution.
The lightning environment for space shuttle design is defined and requirements that the design must satisfy to insure protection of the vehicle system from direct and indirect effects of lightning are imposed. Specifications, criteria, and guidelines included provide a practical and logical approach to protection problems.
Planning requirements identified in this study cover a range of functions including management plans, payload planning, optimization and analysis, flight and mission planning, and mission reporting, as well as all the design, integration and test functions that are hardware oriented. Some of the above functions would be done only once for the entire program, others would be done once for each payload, and others are applicable to each of the many experiments or end items in each payload.
Presented are the results of extensive testing of two 30-cm ion thrusters which are virtually identical to the 900 series Engineering Model Thruster in an ongoing 15,000-hour life test. Included are performance data for the nominal full-power (2650 W) operating point; performance sensitivities to discharge voltage, discharge losses, accelerator voltage, and magnetic baffle current; and several power throttling techniques (maximum Isp, maximum thrust/power ratio, and two cases in between). Criteria for throttling are specified in terms of the screen power supply envelope, thruster operating limits, and control stability. In addition, reduced requirements for successful high voltage recycles are presented.
Power levels up to 100 kWe average were baselined for the electrical power system of the space construction base, a long-duration manned facility capable of supporting manufacturing and large scale construction projects in space. Alternatives to the solar array battery systems discussed include: (1) solar concentrator/brayton; (2) solar concentrator/thermionic; (3) isotope/brayton; (4) nuclear/brayton; (5) nuclear thermoelectric; and (6) nuclear thermionic.
Data on the NASA-University relationship are reported that encompass research in over 600 schools through several thousand grants and contracts. This user-driven system is capable of producing a variety of cyclical and query-type reports describing the total NASA-University profile. The capabilities, designed as part of the system, require a minimum of user maintenance in order to ensure system efficiency and data validity to meet the recurrent Statutory and Executive Branch information requirements as well as ad hoc inquiries from NASA general management, Congress, other Federal agencies, private sector organizations, universities and individuals. The data base contains information on each university, the individual projects and the financial details, current and historic, on all contracts and grants. Complete details are given on the system from its unique design features to the actual steps required for daily operation.
Specific cases of known or potentially useful applications of remote sensing in assessing biological resources are discussed. It is concluded that the more usable remote sensing techniques relate to the measurement of population fluctuations in aquatic systems. Sensing of the flora and the fauna of the Bay is considered with emphasis on direct sensing of aquatic plant populations and of water quality. Recommendations for remote sensing projects are given.
The remote sensing technology required for locating, identifying, and monitoring nonpoint, or diffuse, pollution caused by improper land use practices is discussed. Establishment of an information system to include all remote sensed data acquired on the Bay and to disseminate information to users is considered.
The FORTRAN computing program predicts flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuels of varying end point and hydrogen content specifications. The program has a provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.
A rotorcraft nonlinear simulation called REXOR II, divided into three volumes, is described. The first volume is a development of rotorcraft mechanics and aerodynamics. The second is a development and explanation of the computer code required to implement the equations of motion. The third volume is a user's manual, and contains a description of code input/output as well as operating instructions.
There are no author-identified significant results in this report.
There are no author-identified significant results in this report.
Potentially feasible system concepts for providing additional power, thermal control, and attitude to the baseline orbiter were investigated in order to support a greater variety of space missions and to extend the orbiter's ability to remain in orbit. Results of these analyses include an incremental growth plan that offers the flexibility of adding capability as, and when, it is needed in order to satisfy emerging user requirements.
Near term, cost effective concepts were defined to augment the power and duration capability offered to shuttle payload users. Feasible concept options that could evolve to provide free-flying power and other services to users in the 1984 time frame were also examined.