Hydromagnetic observations in the solar wind
Plasma experiments on Explorer 34 satellite to study fluid properties of solar wind
Burlaga, L. F.↗
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Performance capabilities of liquid-metal MHD induction generators.
Liquid metal MHD induction generators design and performance, considering effect of geometry, operating conditions, fluid properties and power level on efficiency
Elliott, D. G.↗
Laminar flow between two infinite disks, one rotating and the other stationary
Constant property fluid laminar flow between rotating and stationary infinite disks for limiting Reynolds numbers based on gap width
Reshotko, E.↗
Analysis of face deformation effects on gas film seal performance
Analyses are presented for compressible fluid flow across shaft face seals with face deformation. The solutions are obtained from an approximate integral analysis. The models, used in this analysis, can predict gas film seal behavior operating at subsonic or choked flow conditions. The flow regime can either be laminar or turbulent. Entrance losses can also be accounted for. When fluid inertia effects are negligible and the sealing faces are slightly deformed, the following results are found for both laminar and turbulent flows: (1) The pressure profiles are independent of fluid properties; and (2) the parallel film leakage equation can be used, provided a characteristic film thickness is used. Pressure profiles are presented for both divergent and convergent seal faces under choked flow conditions.
Zuk, J.↗
Correlation of Apollo oxygen tank thermodynamic performance predictions
Parameters necessary to analyze the stratified performance of the Apollo oxygen tanks include g levels, tank elasticity, flow rates and pressurized volumes. Methods for estimating g levels and flow rates from flight plans prior to flight, and from quidance and system data for use in the post flight analysis are described. Equilibrium thermodynamic equations are developed for the effects of tank elasticity and pressurized volumes on the tank pressure response and their relative magnitudes are discussed. Correlations of tank pressures and heater temperatures from flight data with the results of a stratification model are shown. Heater temperatures were also estimated with empirical heat transfer agreement with flight data when fluid properties were averaged rather than evaluated at the mean film temperature.
Patterson, H. W.↗
Wall temperature distribution calculation for a rocket nozzle contour
The JANNAF turbulent boundary layer (TBL) computer program, applicable to rocket nozzles, requires a wall temperature distribution among other input parameters to determine boundary layer behavior, heat transfer, and performance degradation. The inclusion of a complete regenerative cooling cycle model with associate geometry, material and fluid property data provides a capability to internally calculate wall temperature profiles on the hot gas and coolant flow-side, as well as the coolant flow bulk temperature variation. Besides the regular heat transfer and performance degradation calculations, the new concept can be used to optimize the cooling cycle, flow requirements, and cooling jacket geometry.
Omori, S.↗
The turbulent boundary layer on a porous plate - Experimental heat transfer with uniform blowing and suction, with moderately strong acceleration.
Experimental data are presented for heat transfer to the turbulent boundary layer subjected to transpiration and acceleration at constant values of the acceleration parameter K of approximately .00000145. This is a moderately strong acceleration, but not so strong as to result in laminarization of the boundary layer. The results for transpiration fractions F of -0.002, 0.0, and +0.0058 are presented in detail in tabular form, and in graphs of Stanton number versus enthalpy thickness Reynolds number. In addition, temperature profiles at several stations are presented. Stanton number results for F = -0.004, +0.002, and +0.004 are also presented, but in graphical form only. The data were obtained using air as both the free-stream and the transpired fluid, at relatively low velocities, and with temperature differences sufficiently low so that the influence of temperature-dependent fluid properties is minimal. All data were obtained with the surface maintained at a temperature invariant in the direction of flow.
Thielbahr, W. H.↗
Anode heat transfer for a flowing argon plasma at elevated electron temperature.
Theoretical investigation of heat transfer from a preionized gaseous plasma flowing over an anode surface at an elevated electron temperature in the presence of an electric field normal to the surface. A laminar boundary layer is considered in which only the velocity profile is locally similar and fluid properties are assumed to change uniformly in the gas flow direction. Results obtained by an approximation method show that for moderate current densities, the velocity and temperature distributions are insensitive to current. In addition, the effect of elevated electron temperature is negligible on convective heat transfer, but is significant for the overall heat transfer due to the enthalpy transport by current. Total heat flux to the anode is obtained by evaluating the Nusselt number and adding terms due to the potential drop in the sheath and the surface work function.
Bose, T. K.↗
Limited cavitation and the related scale effects problem.
It is indicated that the study of limited cavitation can be divided into two parts, namely, the factors which influence the pressure field, and those which influence the bubble dynamics. Major aspects of cavitation nuclei and bubble dynamics are summarized. An analysis is presented of the effects of velocity, size and fluid properties, including the thermodynamic effect. The effects of turbulence, roughness and polymer additives are presented. These include new data on roughness and estimates of the effects of turbulence and polymer additives on jets. An analysis of nonvaporous cavitation with new data on vortex cavitation is presented. Implications concerning scale effects are given.
Holl, J. W.↗
Supersonic turbulent boundary-layer flows with tangential slot injection.
An implicit finite-difference method has been developed for the solution of the compressible boundary-layer equations. This method is applied to tangential slot injection into supersonic turbulent boundary-layer flows. In addition, the effects induced by the interaction between the boundary-layer displacement thickness and the external pressure field are considered. Three different eddy viscosity models have been used to specify the turbulent momentum exchange. One model depends on the species concentration profile, and the species conservation equation has been included in the system of governing partial differential equations. For air injected into air, the freestream and injected gases are treated as separate species which have common fluid properties. Calculations were made and results were compared with experimental data at freestream Mach numbers of 2.4 and 6.0 and with results of another finite-difference method. Good agreement was obtained for the reduction of wall skin friction with slot injection.
Miner, E. W.↗
Measurement techniques for supersonic combustion testing
Measurement techniques used during nine years of intensive research in supersonic combustion are presented. The tests employed a number of combustor and injector configurations, which were directly connected to a Mach 3.2 supersonic nozzle, and both gaseous hydrogen and storable liquid fuels. Nominal plenum conditions for the arc-heated air were 3000 to 4500 R and 30 atm. Measurements included wall surface pressures, wall temperatures, heat flux, skin friction, instream cone-static and pitot pressures, and gas samples. Measurement and analysis techniques have been developed for determining total enthalpy of an airstream containing NO concentrations in excess of equilibrium using the two-throat technique, bulk combustion efficiency using steam calorimetry, radial gradients of fluid properties in the combustor exit plane using a stream tube method, and wall shear from measurements of heat transfer in a reacting supersonic flow using Reynolds analogy.
Orth, R. C.↗
Experimental and analytical investigation of flow through rocket pump inducer
The characteristics of a rocket pump inducer are discussed. The effect of the pumping requirements on the blade configuration is analyzed. The effects of viscosity on blade design were determined by tests of a four bladed inducer operated in air at a flow coefficient of 0.065. The fluid properties were measured at the exit of the inducer using conventional and hot wire probes. The experimental results and the method of predicting the outlet tangential velocity and head rise are discussed.
Lakshminarayana, B.↗
Computer Program for the Design and Off-Design Performance of Turbojet and Turbofan Engine Cycles
The rapid computer program is designed to be run in a stand-alone mode or operated within a larger program. The computation is based on a simplified one-dimensional gas turbine cycle. Each component in the engine is modeled thermo-dynamically. The component efficiencies used in the thermodynamic modeling are scaled for the off-design conditions from input design point values using empirical trends which are included in the computer code. The engine cycle program is capable of producing reasonable engine performance prediction with a minimum of computer execute time. The current computer execute time on the IBM 360/67 for one Mach number, one altitude, and one power setting is about 0.1 seconds. about 0.1 seconds. The principal assumption used in the calculation is that the compressor is operated along a line of maximum adiabatic efficiency on the compressor map. The fluid properties are computed for the combustion mixture, but dissociation is not included. The procedure included in the program is only for the combustion of JP-4, methane, or hydrogen.
Morris, S. J.↗
Solar wind stream interfaces
Results are presented for a superposed epoch analysis of discontinuous solar wind interfaces. The average time-space profiles of stream interfaces are discussed with reference to fluid properties (flow speed, pressure ridge, density, electron and proton temperatures) and kinetic properties (electron core and halo, flow speed fluctuations, electron heat flux, alpha particles). Other aspects of stream interfaces are described, such as the persistence of individual interfaces, shock associations, the sector boundaries of the interplanetary magnetic field, and sudden impulses in the geomagnetic field. Interface position is considered in terms of the observed temperature jump. A conceptual model of high-speed stream evolution is proposed.
Gosling, J. T.↗
Contoured tank outlets for draining of cylindrical tanks in low-gravity environment
An analysis is presented for defining the outlet contour of a hemispherical-bottomed cylindrical tank that will prevent vapor ingestion when the tank is drained. The analysis was used to design two small-scale tanks that were fabricated and then tested in a low gravity environment. The draining performance of the tanks was compared with that for a tank with a conventional outlet having a constant circular cross-sectional area, under identical conditions. Even when drained at off-design conditions, the contoured tank had less liquid residuals at vapor ingestion than the conventional outlet tank. Effects of outflow rate, gravitational environment, and fluid properties on the outlet contour are discussed. Two potential applications of outlet contouring are also presented and discussed.
Symons, E. P.↗
Correlations of thermodynamic effects for developed cavitation
The net positive suction head (NPSH) requirements for a pump are determined by the combined effects of cavitation, fluid properties, pump geometry, and pump operating point. An important part of this determination is the temperature depression (Delta T). Correlations are presented of the temperature depression for various degrees of developed cavitation on venturis and ogives. These correlations, based on a semi-empirical entrainment theory, express Delta T in terms of the dimensionless numbers of Nusselt, Reynolds, Froude, Weber, and Peclet, and dimensionless cavity length (L/D). The Delta T data were obtained in Freon 114, hydrogen and nitrogen for the venturis and in Freon 113 and water for the ogives.
Billet, M. L.↗
Fermi acceleration and the structure of interstellar turbulence
Recent observations at length scales of at least about 10 to the 18th cm and about 10 to the 11th cm suggest the possibility of a generally turbulent interstellar gas with a Kolmogorov spectrum. The total r.m.s. fluctuation in fluid properties is of the same order as the mean. The consequences of such a turbulence spectrum for cosmic rays are discussed. If the turbulence is composed of Alfven waves propagating in both directions along the average magnetic field, the rate of Fermi acceleration is found to be significant. Consequences of the turbulence for spatial transport and the general dynamics of the interstellar gas, as well as possible energy sources for the turbulence, are discussed. It is concluded that Fermi acceleration by interstellar turbulence is a possible acceleration mechanism for galactic cosmic rays.
Jokipii, J. R.↗
Theory of deposition of condensible impurities on surfaces immersed in combustion gases
The components resulting from the deposition of inorganic salts (e.g., Na2S04) and oxides present in the combustion products from gas turbine engines were investigated. Emphasis was placed on the effects of multicomponent vapor transport, thermophoretic transport of vapor and small particles to actively cooled surfaces, variable fluid properties within mass transfer boundary layers, and free stream turbulence.
Rosner, D. E.↗