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Petrie, S. L.

Publications and source records attributed to Petrie, S. L..

Preliminary aerothermodynamic design method for hypersonic vehicles

Preliminary design methods are presented for vehicle aerothermodynamics. Predictions are made for Shuttle orbiter, a Mach 6 transport vehicle and a high-speed missile configuration. Rapid and accurate methods are discussed for obtaining aerodynamic coefficients and heat transfer rates for laminar and turbulent flows for vehicles at high angles of attack and hypersonic Mach numbers.

Harloff, G. J.

Investigations of transonic trailing edge flows

An experimental study of several of the trailing edge and wake turbulence properties for a NACA 64A010 airfoil section was completed. The experiments were conducted at the Ohio State University Aeronautical and Astronautical Research Laboratory in the 6 inch x 22 inch transonic wind tunnel facility. The data were obtained at a free stream Mach number of 0.80 and a flow Reynolds number (based on chord length) of 5 million. The principal diagnostic tool was a dual-component laser Doppler velocimeter. The experimental data included surface static pressures, chordwise and vertical mean velocities, RMS turbulence intensities, local flow angles, and a determination of turbulence kinetic energy in the wake at chordwise locations between the transonic shock wave and the trailing edge, in the near wake just downstream of the trailing edge and in the far wake. At the two angles of attack tested (0 and 2 degrees), the turbulence intensities and turbulence kinetic energy were observed to decay in the streamwise direction. In the far wake, for the non-lifting case, the turbulence intensities were nearly isotropic. For the two degree case, the horizontal component of the turbulence intensity was observed to be substantially higher than the vertical component.

Petrie, S. L.

Experimental analyses of trailing edge flows

An experimental study of several of the trailing edge and wake turbulence properties for a NACA 64A010 airfoil section was completed. The experiment was conducted at the Ohio State University Aeronautical and Astronautical Research Laboratory in the 6 inch X 22 inch transonic wind tunnel facility. The data were obtained at a free stream Mach number of 0.80 and a flow Reynolds number (based on chord length) of 5 million. The principle diagnostic tool was a dual-component laser Doppler velocimeter. The experimental data included surface static pressures, chordwise and vertical mean velocities, RMS turbulence intensities, local flow angles, and a determination of turbulence kinetic energy in the wake. Two angles of attack (0 and 2 degrees) were investigated. At these incidence angles, four flow field surveys were obtained ranging in position from the surface of the airfoil, between the transonic shock and the trailing edge, to the far-wake. At both angles of attack, the turbulence intensities and turbulence kinetic energy were observed to decay in the streamwise direction. In the far wake, for the non-lifting case, the turbulence intensities were nearly isotropic. For the two degree case, the horizontal component of the turbulence intensity was observed to be substantially higher than the vertical component.

Petrie, S. L.

Modeling techniques for transonic airfoils

In the present comparative study of computer codes for the modeling of two-dimensional, single element airfoil sections for various section geometry classes, two of the codes use vortex singularities methods to obtain the potential flow solution while the remainder solve the full inviscid potential flow equations by means of finite differencing techniques that allow results to be obtained for transonic flow about an airfoil which includes weak shocks. Computational results are presented for a symmetrical airfoil section, a conventional section, and a supercritical one. Icing condition applications of the models are noted. The model codes' range of applicability and agreement with each other and experimental results, as well as their computer run times and memory requirements, are noted.

Petrie, S. L.

Unsteady pressures on a NACA 64A010 airfoil - Experimental and theoretical results

Transonic testing of an NACA 64A010 airfoil at the Ohio State University Aero-Astro Research Laboratory is described, and results of fixed angle of attack and pitch oscillation experiments are discussed. The operating range was Mach 0.20 to 1.07 with available total pressures of 140,000 N/m2 to 620,000 N/m2. The airfoil model was mounted on roller bearings installed in the solid sidewalls of the tunnel test section. The equipment included transducers to measure unsteady pressures, and static pressure taps obtaining steady-state data. The data gathered at Mach 0.8 gave an indication of the influence of the natural shock instability and shock-induced flow separation on the unsteady pressures, with the location of the peak disturbance level shifting forward in the comparison of 0 to 2 deg pitch angle data. The oscillating airfoil data is examined in terms of harmonic content and the in-phase and out-of-phase components. It is concluded that the experimental data has good qualitative comparison with methods accounting for shock interaction.

Davis, J. A.

Electron beam diagnostics.

Spectroscopic electron beam diagnostic technique, examining negligible effect elevated vibrational temperatures have on measured rotational temperatures of molecular nitrogen

ELECTRON BEAM