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Report documents evaluation test on commercial flat-plate solar collector that uses water as working fluid. Performance was measured before and after 34-day exposure to natural environment. Tables in metric and English units present data on air and water temperatures, waterflow, insolation, efficiency, and windspeed and direction.
The procedures used and the results obtained during the evaluation test program on the S. N. 1, (liquid) solar collector are presented. The flat plate collector uses water as the working fluid. The absorber plate is aluminum with plastic tubes coated with urethane black. The glazing consists of .040 in fiberglass reinforced polyester. The collector weight is 78.5 pounds with overall external dimensions of approximately 50.3in. x 98.3in. x 3.8in. The following information is given: thermal performance data under simulated conditions, structural behavior under static loading, and the effects of long term exposure to natural weathering. These tests were conducted using the MSFC Solar Simulator.
The overall objectives of the Phase IV Solid Polymer Electrolyte Fuel Cell Technology Program were to: (1) establish fuel cell life and performance at temperatures, pressures and current densities significantly higher than those previously demonstrated; (2) provide the ground work for a space energy storage system based on the solid polymer electrolyte technology (i.e., regenerative H2/O2 fuel cell); (3) design, fabricate and test evaluate a full-scale single cell unit. During this phase, significant progress was made toward the accomplishment of these objectives.
A 256 word by 8-bit random access memory chip was developed utilizing p channel, metal gate metal-nitride-oxide-silicon (MNOS) technology; with operational characteristics of a 2.5 microsecond read cycle, a 6.0 microsecond write cycle, 800 milliwatts of power dissipation; and retention characteristics of 10 to the 8th power read cycles before data refresh and 5000 hours of no power retention. Design changes were implemented to reduce switching currents that caused parasitic bipolar transistors inherent in the MNOS structure to turn on. Final wafer runs exhibited acceptable yields for a die 250 mils on a side. Evaluation testing was performed on the device in order to determine the maturity of the device. A fixed gate breakdown mechanism was found when operated continuously at high temperature.
Procedures used and results obtained during the evaluation test program on a flat plate collector which uses water as the working fluid are discussed. The absorber plate is copper tube soldered to copper fin coated with flat black paint. The glazing consists of two plates of Lo-Iron glass; the insulation is polyurethane foam. The collector weight is 242.5 pounds with overall external dimensions of approximately 48.8 in. x 120.8 in. x 4.1 in. The test program was conducted to obtain thermal performance data before and after 34 days of weather exposure test.
Feasibility of the annular momentum control device (AMCD) for the control and stabilization of spacecraft is presented. The AMCD is momentum storage equipment consisting of a thin rim, magnetically suspended and rotated by noncontacting electromagnetic actuators. The laboratory model AMCD, the rim, and the magnetic suspension system are described, along with their evaluation tests. Because it utilizes permanent magnet flux biased magnetic bearing elements, the original laboratory model magnetic suspension system produced control limitations, and a new suspension system which used zero flux bias was designed and fabricated. Tests of the improved system show that a medium control loop bandwidth is required to achieve stability at low rim velocities, but at higher rim speed the bandwidth of the control loop interacts with bending modes of the rim and causes instability. Decreasing the bandwidth by changing to a precession control mode is discussed, and the results of such a computer simulation are presented.
Commercial tracking collector that uses acrylic Fresnel lenses to focus Sunlight on copper absorber tubes was evaluated. Tests are documented in 16 page report.
Report presents results of performance evaluation. Tests are part of continuing study of solar-heating systems and components for NASA and Department of Energy. Test data are presented as graphs and tables. Report also summarizes test procedures and mathematical analysis of results.
The procedures used and the results obtained during the evaluation test program on the Solar Unlimited, Inc., Suncatcher SH-11 (liquid) solar collector are presented. The flat-plate collector case assembly is made of .08 inch aluminum 3003 H14 riveted with fiberglass board insulation. The absorber consists of collared aluminum fins mechanically bonded to 3/8 inch copper tubing and coated with 3M Nextel black. Water is used as the working fluid. The glazing is made of a single glass, 1/8 inch water white, tempered and antireflective. The collector weight is 85 pounds with overall external dimensions of about 35.4 in x 82.0 in x 4.0 in. Thermal performance data on the Solar Unlimited Suncatcher SH-11 solar collector under simulated conditions were conducted using the MSFC Solar Simulator.
A series of acoustic tests were conducted on the over the wing engine. These tests evaluated the fully suppressed noise levels in forward and reverse thrust operation and provided insight into the component noise sources of the engine plus the suppression achieved by various components. System noise levels using the contract specified calculation procedure indicate that the in-flight noise level on a 152 m sideline at takeoff and approach are 97.2 and 94.6 EPNdB, respectively, compared to a goal of 95.0 EPNdB. In reverse thrust, the system noise level was 106.1 PNdB compared to a goal of 100 PNdB. Baseline source noise levels agreed very well with pretest predictions. Inlet-radiated noise suppression of 14 PNdB was demonstrated with the high throat Mach number inlet at 0.79 throat Mach number.
Work performed in support of radiation and convective base heating predictions in developing the space shuttle thermal environment is described. Topics discussed include plume radiation predictions and the development of prediction methods; convective base heating predictions due to both reversed flow and direct plume impingement; and evaluation testing of a gas temperature probe used in short-duration base heating model tests.
This bibliography lists 341 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1980. Abstracts on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems are presented. Research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles are also presented.
The use of a self pulsed laser system for accurately describing the surface shape of large space deployed antenna structures was evaluated. Tests with a breadboard system verified functional operation with short time resolution on the order of .2 mm, nonambiguous ranging, and a maximum range capability on the order of 150 m. The projected capability of the system is resolution of less than .1 mm over a reasonable time period and a range extension to over 300 m.
A bibliography containing 431 abstracts addressing various topics in aeronautical engineering is given. The coverage includes engineering and theoretical aspects of design. construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles.
Results are presented from the shakedown and evaluation test of a bulk calorimeter. The calorimeter is designed to quench the combustion at the exit of a direct-connect, hydrogen fueled, scramjet combustor model, and to provide the measurements necessary to perform an analysis of combustion efficiency. Results indicate that the calorimeter quenches reaction, that reasonable response times are obtained, and that the calculated combustion efficiency is repeatable within + or -3 percent and varies in a regular way with combustor model parameters such as injected fuel equivalence ratio.
A clear air turbulence (CAT) flight test to evaluate and test four different sensors in the detection and measuring of CAT and other meteorological targets that relate to turbulence is discussed. The primary types of CAT investigated were mountain wave CAT, jetstream CAT, CAT in cirrus clouds, and CAT in frontal wind shears, troughs, and ridges. The sensors included the CO2 pulsed Doppler lidar and three radiometers. One of the radiometers, at a frequency of 55.5 GHz, looked at atmospheric temperature structure. Another, at a frequency of 180.1 GHz, looked at atmospheric water vapor and investigated the feasibility of measuring at the microwave frequency the turbulence features seen in the infrared (IR) frequencies. An IR radiometer at 27 to 33 microns was the fourth sensor. This last device and the temperature structure radiometer worked well at all flight levels.
The post-test evaluation of a single heat exchanger sodium hydroxide thermal energy storage module for use in solar electric generation is reported. Chemical analyses of the storage medium used in the experimental model are presented. The experimental verification of the module performance using an alternate heat transfer fluid, Caloria HT-43, is described. Based on these results, a design analysis of a dual heat exchanger concept within the storage module is presented. A computer model and a reference design for the dual system (storage working fluid/power cycle working fluid) were completed. The dual system is estimated to have a capital cost of approximately one half that of the single heat exchanger concept.
The objective of Sarsat is to demonstrate that satellites can greatly facilitate the monitoring, detection, and location of distress incidents alerted by Emergency Locator Transmitters (ELTs) and Emergency Position Indicating Radio Beacons (EPIRBs) carried on commercial, military, and general aviation aircraft and some marine vessels. The detection and location will be accomplished by relaying, via satellite, ELT/EPIRB distress information to ground stations, which will complete the data processing and forward alert and position location data to rescue coordination services. This paper presents a Sarsat system description and a summary of Coast Guard and USAF objectives for the initial demonstration and evaluation tests of Sarsat.