Flowfield measurements in the vortex wake of a missile at high angle of attack in turbulence
Approved for public release; distribution is unlimited === The flowfield downstream of a vertically-launched surface-to-air missile model at an angle of attack of 50° and a Reynolds number of 1.1 x 10(5) was investigated in a wind tunnel of the Naval Postgraduate School. The goal of this thesis is t...
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| Format: | Others |
| Language: | en_US |
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Monterey, California. Naval Postgraduate School
Dece
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| Online Access: | http://hdl.handle.net/10945/23235 |
| Summary: | Approved for public release; distribution is unlimited === The flowfield downstream of a vertically-launched surface-to-air missile model at an angle of attack of 50° and a Reynolds number of 1.1 x 10(5) was investigated in a wind tunnel of the Naval Postgraduate School. The goal of this thesis is to experimentally validate the pressure measurement system for flowfield variables with elevated levels of turbulence; to determine the location and intensity of the asymmetric vortices in the wake of the VLSAM model at a raised level of freestream turbulence; and to display the asymmetric vortices by velocity mapping and pressure contours. The purpose is to correlate the results with the force measurements of Rabang to provide a greater
understanding of the vortex flowfield. The body-only configuration was tested. Two flowfield
conditions were treated: the nominal ambient wind tunnel condition, and a condition with grid
generated turbulence of 3.8% turbulence intensity and a dissipation length scale of 1.7 inches. The following conclusions were reached: 1) The relative strengths of the asymmetric vortices can be noted by the sharp spike shape in the ambient condition; this condition becomes diffused and becomes fatter in the turbulent condition; 2) The right side vortex has greater strength than the left side one as seen by the diffusion in the total pressure coefficient and static pressure coefficient contours with and without a turbulent condition; 3) an increase in turbulence intensity tends to reduce the strength of the asymmetric nose-generated vortices; also pushes the two asymmetric vortices closer together; 4) and crossflow velocities were examined and
were found to indicate the behavior denoted by the pressure contours. === http://archive.org/details/flowfieldmeasure00lung === Lieutenant, Republic of China Navy |
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