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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Experimental heat transfer and flow results of a chordwise-finned turbine vane with impingement, film, and convection cooling

Experimental heat transfer data are presented for a vane tested in a turbojet engine at turbine inlet gas temperatures to 1644 K (2500 F), coolant temperatures to 700 K (800 F), and coolant-to-gas flow ratios to 0.187. Methods are presented for correlating heat transfer data and obtaining coolant flow distribution through the vane. Calculated and measured coolant flow distributions and vane metal temperatures are compared.

Gauntner, J. W.↗
NASA NTRS1973

Study of high altitude plume impingement

The radiation intensities are determined in the base region of the space shuttle due to solid particle radiation emanating from the solid rocket motors of the shuttle. Results of an analysis of the Titan 3 and simulated solid rocket motor radiation intensities are presented. The gas particle flow fields of the Titan 3 nozzle and plume and a space shuttle solid rocket motor nozzle and plume are described. The gaseous Titan 3 flow fields are discussed utilizing the results of flow fields generated by a gaseous and two phase method-of-characteristics computer programs. A two phase computer flow field analysis program was developed. An outflow correction theory is developed which will be used to modify existing convection heat transfer methods for better heat transfer predictions on bodies immersed in rocket exhaust plumes.

Mcanally, J. V.↗
NASA NTRS1973

Dynamic loading of aircraft surfaces due to jet exhaust impingement

High-lift wing concepts being considered for application to commercial STOL transports are discussed. The flow patterns which produce dynamic loads on these wings are indicated. Measurements of surface pressure and acceleration on a one-half-scale model of an externally blown double-slotted flap are reported. Root-mean-square values, power spectra, and scaling parameters are shown.

Lansing, D. L.↗
NASA NTRS1973

Interference heating due to shock wave impingement on laminar boundary layers.

Laminar interference heating correlations have been developed based on recent experimental data obtained with wedge/flat plate models for wide ranges of Reynolds number and shock strength. Two correlation techniques were developed using the Eckert reference method. The peak interference Stanton number was first correlated with shock strength, Reynolds number, and Prandtl number based on flow conditions upstream of the interference region. The second approach was made by correlating peak interference Stanton number with only Reynolds number and Prandtl number based on downstream flow conditions. The laminar boundary layer remains laminar when both Reynolds number and shock strength are low but becomes transitional or turbulent when Reynolds number or/and shock strength are increased.

Hung, F. T.↗
NASA NTRS1974

Pressure-loss and flow coefficients inside a chordwise-finned, impingement, convection, and film air-cooled turbine vane

Total-pressure-loss coefficients, flow discharge coefficients, and friction factors were determined experimentally for the various area and geometry changes and flow passages within an air-cooled turbine vane. The results are compared with those of others obtained on similar configurations, both actual and large models, of vane passages. The supply and exit air pressures were controlled and varied. The investigation was conducted with essentially ambient-temperature air and without external flow of air over the vane.

Hippensteele, S. A.↗
NASA NTRS1974

Research on free and impinging jets for the development of STOL aircraft

The effect of the exit plane conditions on the initial region of an axisymmetric jet was systematically investigated. An essentially top-hat mean velocity profile and a homogeneous turbulence structure were maintained at the exit plane for eight distinct scale and intensity conditions. Mass and momentum flux values are independent of the exit turbulence structure for the range investigated; however, a significant (approximately 25%) increase in the latter implies a pronounced static pressure decrement inside the jet. Details of the velocity profile and turbulence structure are influenced by the exit plane conditions. The three radial-axial components of the Reynolds stress tensor have been conditionally sampled and are analyzed to show the initial condition effects.

Foss, J. F.↗
NASA NTRS1976

The plume impingement test program at AEDC utilizing the S-2 ullage motors (November 1973), section 1

Proposed experiments for analyzing rocket plumes are reported. Two groups of experiments were studied: (1) those that would help define some of the parameters that characterize the plume and (2) those that would enable evaluation of some of the contamination effects of the plume environment on various items of interest. The items investigated, the purpose of the investigation, are given in tabular form.

Source record↗
NASA NTRS1976

The large motor plume/material impingement test program at AEDC utilizing the four selected propellants from the small motor tests at MSFC (July, August, and September 1974), section 3

Efforts made to determine the vulnerability of Orbiter and ET materials located at various positions within exhaust plumes from test SSRM's using four different propellant formulations are discussed. Data also cover the effect on TPS materials from a single SSRM plume and dual SSRM plumes, and definitions of test SSRM plume environment at material specimen locations.

Source record↗
NASA NTRS1976

Noise generated by impingement of turbulent flow on airfoils of varied chord, cylinders, and other flow obstructions

Noise spectra were measured in three dimensions for several surfaces immersed in turbulent flow from a jet and over a range of flow conditions. The data are free field and were corrected to remove the small contributions of jet noise, atmospheric attenuation and feedback tones. These broadband data were compared with the results of available theories which are only strictly applicable to simple geometries over a limited range of conditions. The available theories proved to be accurate over the range of flow, chord length, thickness, angle of attack, and surface geometries defined by the experiments. These results apply to the noise generated by fixed surfaces in engine passages, the lifting surfaces of aircraft and also to fan noise.

Olsen, W. A.↗
NASA NTRS1976

Noise generated by impingement of turbulent flow on airfoils of varied chord, cylinders, and other flow obstructions

Noise spectra were measured in three dimensions for several surfaces immersed in turbulent flow from a jet and over a range of flow conditions. The data are free field and were corrected to remove the small contributions of jet noise, atmospheric attenuation and feedback tones. These broadband data were compared with the results of available theories which are only strictly applicable to simple geometries over a limited range of conditions. The available theories proved to be accurate over the range of flow, chord length, thickness, angle of attack, and surface geometries defined by the experiments. These results apply to the noise generated by fixed surfaces in engine passages, the lifting surfaces of aircraft and also to fan noise.

Olsen, W. A.↗
NASA NTRS1977

Site Alteration Effects from Rocket Exhaust Impingement During a Simulated Viking Mars Landing. Part 2: Chemical and Biological Site Alteration

Chemical and biological alteration of a Mars landing site was investigated experimentally and analytically. The experimental testing was conducted using a specially designed multiple nozzle configuration consisting of 18 small bell nozzles. The chemical test results indicate that an engine using standard hydrazine fuel will contaminate the landing site with ammonia (50-500ppm), nitrogen (5-50ppm), aniline (0.01-0.5ppm), hydrogen cyanide (0.01-0.5ppm), and water. A purified fuel, with impurities (mostly aniline) reduced by a factor of 50-100, limits the amount of hydrogen cyanide and aniline to below detectable limits for the Viking science investigations and leaves the amounts of ammonia, nitrogen, and water in the soil unchanged. The large amounts of ammonia trapped in the soil will make interpretation of the organic analysis investigation results more difficult. The biological tests indicate that the combined effects of plume gases, surface heating, surface erosion, and gas composition resulting from the retrorockets will not interfere with the Viking biology investigation.

Husted, R. R.↗
NASA NTRS1979

Inhibition of solar wind impingement on Mercury by planetary induction currents

Analytic methods are developed for taking into account finite planetary conductivity in modeling departures from equilibrium of a magnetospheric boundary caused by solar wind stagnation pressure variations. Using the lowest suggested value of the planetary dipole moment (2.4 x 10 to the 22nd G cu cm), it is estimated that a minimum pressure of about 38 P sub 0 (where P sub 0 is the external stagnation pressure in the steady state) is required to force the standoff distance down to the subsolar surface of Mercury if the pressure change persists for at least 1 day. This value is 4.3 times that which would be predicted if Mercury had no core, and it is larger than the maximum pressure predicted at Mercury's orbit (about 25 P sub 0) on the basis of hourly averaged solar wind statistics at 1 AU.

Hood, L. L.↗