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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 847 records · Page 47
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Modifications to the nozzle test chamber to extend nozzle static-test capability

The nozzle test chamber was modified to provide a high-pressure-ratio nozzle static-test capability. Experiments were conducted to determine the range of the ratio of nozzle total pressure to chamber pressure and to make direct nozzle thrust measurements using a three-component strain-gage force balance. Pressure ratios from 3 to 285 were measured with several axisymmetric nozzles at a nozzle total pressure of 15 to 190 psia. Devices for measuring system mass flow were calibrated using standard axisymmetric convergent choked nozzles. System mass-flow rates up to 10 lbm/sec are measured. The measured thrust results of these nozzles are in good agreement with one-dimensional theoretical predictions for convergent nozzles.

Keyes, J. W.↗
NASA NTRS1985

SSME seal test program: Test results for hole-pattern damper seals

The results consisting of direct and transverse force coefficients are presented for thirteen, hole-pattern, damper-seal configurations. The designation damper seal refers to a seal which uses a deliberately roughened stator nd smooth rotor, to increase the net damping force developed by a seal. The designation hole-pattern refers to a stator roughness pattern which is developed by a pattern of round holes while are milled into the stator. All seals tested use the same smooth rotor and have the same constant minimum clearance. The seal tests examined the following major design options: (1) hole-area density, i.e., the proportion of stator surface area consumed by holes; and (2) hole depth, particularly the ratio of hole depth to minimum clearance. In addition, limited data were taken to examine the influence of in-line versus staggered hole patterns and flat-bottomed versus spherical-bottomed holes.

Childs, D. W.↗
NASA NTRS1985

Amorphous silicon photovoltaic modules and test devices design, fabrication and testing

In July of 1984, Hughes and JPL initiated a contract for Hughes to design, fabricate and test 10 thin film Amorphous Silicon (a-Si) photovoltaic power modules. These modules were to be 1 ft x 4 ft in size. They were to be preceded by the delivery of 10 a-Si 4 in. square test devices. This effort is very timely since thin film PV development has progressed to the point where intermediate load power applications are on the horizon. It is important to know if current a-Si submodule design and manufacturing processes yield a product that is compatible with the packaging needed to meet a 20 to 30 year life span expectancy. The term submodule is assigned to an interconnected assembly of 28 a-Si cells deposited on a 1 foot square glass superstrate. These assemblies are equipped with electrical terminations, i.e., copper tabs at the four corners of the inverted submodules. It is these submodules that are to be interconnected and packaged into power modules, as opposed to the interconnected individual crystalline cells packaged into todays PV modules. A discussion of the fabrication methods and results follows.

Vanleeuwen, M.↗
NASA NTRS1986

Supplementary calibration test of the tip-aerodynamics- and acoustics-test pressure transducers

A calibration test is described that was performed to supplement the normal calibration of the 188 pressure transducers used in the Tip Aerodynamics and Acoustics Test. This calibration led to the identification of 15 transducers which had a slope change of greater than 7% from the initial calibration. The calibration procedure is described and the results presented. The effect of the slope changes on the pressure distributions are described, followed by a method to compensate for these changes.

Watts, M. E.↗
NASA NTRS1987

Force and moment tests to determine the interaction effects of the reaction control system jet plumes on the space shuttle Orbiter aerodynamics at Mach Number 6 (Test OA352)

The purpose of this test was to expand the existing Space Shuttle aerodynamics and Reaction Control System (RCS) data base to support the Glide Return to Launch Site (GRTLS) abort trajectory and the new Digital Autopilot. An existing model of the orbiter was used to investigate the aerodynamic effects of several combinations of RCS thrusters and thruster momentum ratios at Mach number 6. Two separate model installations were used to achieve an angle-of-attack range of -11 to 46 deg. The test was conducted at a unit Reynolds number of 0.8 x 10 to the 6th per foot.

Cayse, Robert W.↗
NASA NTRS1987

Space Station propulsion system test bed and control system testing results

The test bed fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the IOC Space Station application is described and test results are presented. The reliability and safety of the O2/H2 system was demonstrated with blowdowns and thruster firings. The flexibility of the system was demonstrated through the addition of an electrolysis supply module.

Norman, A. M.↗
NASA NTRS1987

Test flow calibration study of the Langley Arc-Heated Scramjet Test Facility

The test flow at the exits of two square cross-section contoured nozzles with nominal exit Mach numbers of 4.7 and 6 has been studied as calibration data for the NASA-Langley Arc-Heated Scramjet Test Facility over simulated flight conditions from Mach 5.5 (at altitudes from 98,600-128,000 ft) to Mach 7 (at altitudes from 108,000-149,000 ft). Nozzle exit contour maps of measured thermodynamic properties, calculated Mach number, and calculated mass flow are used to determine the mass flow approaching the inlets of various scramjet engines. Good agreement is found between experimentally measured facility total mass flow and facility total mass flow determined by integration of the nozzle exit mass flow contours.

Thomas, Scott R.↗
NASA NTRS1986

Evaluation of the infrared test method for the olympus thermal balance tests

The performance of the infrared (IR) rig used for the thermal balance testing of the Olympus S/C thermal model is discussed. Included in this evaluation are the rig effects themselves, the IRFLUX computer code used to predict the radiation inputs, the Monitored Background Radiometers (MBR's) developed to measure the absorbed radiation flux intensity, the Uniform Temperature Reference (UTR) based temperature measurement system and the data acquisition system. A preliminary set of verification tests were performed on a 1 m x 1 m zone to assess the performance of the IR lamps, calrods, MBR's and aluminized baffles. The results were used, in part, to obtain some empirical data required for the IRFLUX code. This data included lamp and calrod characteristics, the absorptance function for various surface types, and the baffle reflectivities.

Donato, M.↗
NASA NTRS1989

Propfan Test Assessment (PTA): Flight test report

The Propfan Test Assessment (PTA) aircraft was flown to obtain glade stress and noise data for a 2.74m (9 ft.) diameter single rotation propfan. Tests were performed at Mach numbers to 0.85 and altitudes to 12,192m (40,000 ft.). The propfan was well-behaved structurally over the entire flight envelope, demonstrating that the blade design technology was completely adequate. Noise data were characterized by strong signals at blade passage frequency and up to 10 harmonics. Cabin noise was not so high as to preclude attainment of comfortable levels with suitable wall treatment. Community noise was not excessive.

Little, B. H.↗
NASA NTRS1987

Development flight tests of JetStar LFC leading-edge flight test experiment

The overall objective of the flight tests on the JetStar aircraft was to demonstrate the effectiveness and reliability of laminar flow control under representative flight conditions. One specific objective was to obtain laminar flow on the JetStar leading-edge test articles for the design and off-design conditions. Another specific objective was to obtain operational experience on a Laminar Flow Control (LFC) leading-edge system in a simulated airline service. This included operational experience with cleaning requirements, the effect of clogging, possible foreign object damage, erosion, and the effects of ice particle and cloud encounters. Results are summarized.

Fisher, David F.↗
NASA NTRS1989

Ground-based testing of Precision Segmented Reflectors - PSR in the ground test environment

Recent PSR test experiences including panel surface error measurements and a truss beam experiment are covered. Principal environmental concerns, such as one-g condition, ambient microseismic environment, acoustic environment and thermal environment for the PSR testbed are analyzed. Results of the analysis and their implications for ground-based testing of large precision segmented optical systems are presented.

Satter, C. M.↗
NASA NTRS1992

Electromagnetic compatibility (EMC) standard test chamber upgrade requirements for spacecraft design verification tests

In view of the serious performance deficiencies inherent in conventional modular and welded shielding EMC test enclosures, in which multipath reflections and resonant standing waves can damage flight hardware during RF susceptibility tests, NASA-Goddard has undertaken the modification of a 20 x 24 ft modular-shielded enclosure through installation of steel panels to which ferrite tiles will be mounted with epoxy. The internally reflected RF energy will thereby be absorbed, and exterior power-line noise will be reduced. Isolation of power-line filters and control of 60-Hz ground connections will also be undertaken in the course of upgrading.

Dyer, Edward F.↗
NASA NTRS1993

Los Alamos studies of the Nevada test site facilities for the testing of nuclear rockets

The topics are presented in viewgraph form and include the following: Nevada test site geographic location; location of NRDA facilities, area 25; assessment program plan; program goal, scope, and process -- the New Nuclear Rocket Program; nuclear rocket engine test facilities; EMAD Facility; summary of final assessment results; ETS-1 Facility; and facilities cost summary.

Hynes, Michael V.↗
NASA NTRS1943

Some investigations of the general instability of stiffened metal cylinders III : continuation of tests of wire-braced specimens and preliminary tests of sheet-covered specimens

This is the third of a series of reports covering an investigation of the general instability problem by the California Institute of Technology. The first five reports of this series cover investigations of the general instability problem under the loading conditions of pure bending and were prepared under the sponsorship of the Civil Aeronautics Administration. The succeeding reports of this series cover the work done on other loading conditions under the sponsorship of the National Advisory Committee for Aeronautics. This report is concerned primarily with the continuation of the tests of wire-braced specimens, and preliminary tests of sheet-covered specimens that had been made in the experimental investigation on the problem of the general instability of stiffened metal cylinders at the C.I.T.

ALUMINUM ALLOYS, SHEETS, ALCOA 17ST↗
NASA NTRS1927

Description of the NACA Universal Test Engine and Some Test Results

This report describes the 5-inch bore by 7-inch stroke single cylinder test engine used at the Langley Field Laboratory of the National Advisory Committee for Aeronautics in laboratory research on internal-combustion engine problems and presents some results of tests made therewith. The engine is arranged for variation over wide ranges, of the compression ratio and lift and timing of both inlet and exhaust valves while the engine is in operation. Provision is also made for the connection of a number of auxiliaries. These features tend to make the engine universal in character, and especially suited for the study of certain problems involving change in compression ratio, valve timing, and lift.

Ware, Marsden↗
NASA NTRS1930

Wind-Tunnel Tests on a Series of Wing Models Through a Large Angle of Attack Range. Part I : Force Tests

This investigation covers force tests through a large range of angle of attack on a series of monoplane and biplane wing models. The tests were conducted in the atmospheric wind tunnel of the National Advisory Committee for Aeronautics. The models were arranged in such a manner as to make possible a determination of the effects of variations in tip shape, aspect ratio, flap setting, stagger, gap, decalage, sweep back, and airfoil profile. The arrangements represented most of the types of wing systems in use on modern airplanes. The effect of each variable is illustrated by means of groups of curves. In addition, there are included approximate autorotational characteristics in the form of calculated ranges of "rotary instability." a correction for blocking in this tunnel which applies to monoplanes at large angles of attack has been developed, and is given in an appendix. (author)

Knight, Montgomery↗
NASA NTRS1993

NASTRAN Modeling of Flight Test Components for UH-60A Airloads Program Test Configuration

Based upon the recommendations of the UH-60A Airloads Program Review Committee, work towards a NASTRAN remodeling effort has been conducted. This effort modeled and added the necessary structural/mass components to the existing UH-60A baseline NASTRAN model to reflect the addition of flight test components currently in place on the UH-60A Airloads Program Test Configuration used in NASA-Ames Research Center's Modern Technology Rotor Airloads Program. These components include necessary flight hardware such as instrument booms, movable ballast cart, equipment mounting racks, etc. Recent modeling revisions have also been included in the analyses to reflect the inclusion of new and updated primary and secondary structural components (i.e., tail rotor shaft service cover, tail rotor pylon) and improvements to the existing finite element mesh (i.e., revisions of material property estimates). Mode frequency and shape results have shown that components such as the Trimmable Ballast System baseplate and its respective payload ballast have caused a significant frequency change in a limited number of modes while only small percent changes in mode frequency are brought about with the addition of the other MTRAP flight components. With the addition of the MTRAP flight components, update of the primary and secondary structural model, and imposition of the final MTRAP weight distribution, modal results are computed representative of the 'best' model presently available.

Idosor, Florentino R.↗