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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 199 records · Page 11

Characteristics of Perforated Diffusers at Free-stream Mach Number 1.90

An investigation was conducted at Mach number 1.90 to determine pressure recovery and mass-flow characteristics of series of perforated convergent-divergent supersonic diffusers. Pressure recoveries as high as 96 percent were obtained, but at reduced mass flows through the diffuser. Theoretical considerations of effect of perforation distribution on shock stability in converging section of diffuser are presented and correlated with experimental data. A method of estimating relative importance of pressure recovery and mass flow on internal thrust coefficient basis is given and a comparison of various diffusers investigated is made.

FLOW, SUPERSONIC↗

Aerodynamic characteristics of four bodies of revolution showing some effects of afterbody shape and fineness ratio at free-stream Mach numbers from 1.50 to 1.99

The effects of fineness ratio (14.2 and 12.2) and boattailing on aerodynamic characteristics of four bodies of revolution at Mach numbers from 1.50 to 1.99 within a range of angles of attack from 0 degrees 10 degrees at an approximate Reynolds number of 35x10(superscript)6 based on body length were investigated. A comparison of experimental data with available theory is included. At zero angle of attack, fineness ratio has no appreciable effect on model characteristics while boattailing and boattail convergence significantly affect fore drag and base drag. At angle of attack the effects are singular. The theory presented by H. J. Allen is a significant improvement over linearized potential theory in predicting aerodynamic characteristics.

BODIES - FITNESS RATIO↗

Investigation of an Underslung Normal-wedge Inlet at Free-stream Mach Numbers from 1.50 to 1.99

Two normal -wedge-inlet configurations (straight and sweptback splitter plates) were investigated in the Lewis 8- by 6-foot supersonic wind tunnel at Mach numbers of 1.50 to 1.99. Negligible differences occurred in the performances of the two normal-wedge inlets. In comparison with a previously tested scoop inlet, the normal-wedge configuration showed superior thrust-minus-drag characteristics at Mach 1.99. However the scoop inlet was better at Mach numbers of 1.80 and 1.50.

Vargo, Donald J↗