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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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Flow liner eliminates high-cycle fatigue in ducts carrying cryogenic fluids. It is capable of handling two-directional, high-velocity cryogenic liquid flow with a 3-inch axial motion without binding within a 25-inch length.
Studies of the properties of five metals with varying tube-wall thickness, with or without and internal coating of trifluorochloroethylene polymer, show that wall characteristics influence flow stability, affect heat transfer coefficients, and influence the transition point from dry- to wet-wall flow.
Calculation of natural gas flow through critical flow nozzles
Approximation for distribution of flow properties in angle of attack plane of conical flows
Mass flow rate calculation of methane and natural gas mixtures through critical flow nozzles
Polymeric materials flow at tube entrance, discussing pressure drop and flow birefringent patterns at tapered and sharp entrances
Simulating downstream flow blockage doors in bypass air duct of turbofan engine with axial flow fan rotor
Flow-induced vibration of bellows with internal cryogenic fluid flows
Equations for mass flow of methane and natural gas mixtures through critical flow nozzles, including real gas effects
Computer program to generate turbine aerodynamic requirements, approximate external blade geometries, and coolant flow requirements for two stage axial flow turbine
Effect of inlet conditions on flow and containment characteristics of coaxial flows for gas core nuclear rockets
Development of flow measuring apparatus for determining low flow performance of resistojet thruster is discussed. Diagram of test equipment is presented. Operation of test equipment is described and numerical relationships are explained.
An analytical solution for the compressible one-dimensional flow in convergent and divergent ducts with friction is obtained. It is found that a nondimensional parameter, N, can be formed using the friction factor, duct half-angle and the ratio of specific heats of the gas. Seven flow regimes are describable with the solution, based on certain bounds on the magnitude of N. The regimes are discussed and corollary data are presented graphically.
The factors which influence the design and selection of a nozzle for a hypersonic scramjet are described. A two dimensional second-order characteristic procedure capable of analyzing the aerodynamic performance of typical nozzle configurations is presented. Equations of motion governing the two dimensional, axisymmetric, or axially expanding inviscid flow of a gas mixture, with frozen chemistry, are provided. Diagrams of the flow conditions for various configurations are included.
An investigation was made of published nozzle flow separation data in order to determine the parameters which affect the separation condition. A comparison of experimental data with empirical and theoretical separation prediction methods leads to the selection of suitable equations for the separation criterion. The results were used to predict flow separation of the main space shuttle engine.
An analytical model for separated airfoil flows is presented which is based on experimentally observed physical phenomena. These include a free stagnation point aft of the airfoil and a standing vortex in the separated region. A computer program is described which iteratively matches the outer potential flow, the airfoil turbulent boundary layer, the separated jet entrainment, mass conservation in the separated bubble, and the rear stagnation pressure. Separation location and pressure are not specified a priori. Results are presented for surface pressure coefficient and compared with experiment for three angles of attack for a GA(W)-1, 17% thick airfoil.
A summary is given of the attempts made to apply semidirect methods to the calculation of three-dimensional viscous flows over suction holes in laminar flow control surfaces. The attempts were all unsuccessful, due to either (1) lack of resolution capability, (2) lack of computer efficiency, or (3) instability.
The use of inviscid-viscous interaction methods for the case of radial or mixed-flow cascade diffusers is discussed. A literature review of investigations considering cascade flow-field prediction by inviscid-viscous iterative computation is given. Cascade aerodynamics in the third blade row of a multiple-row radial cascade diffuser are specifically investigated.