Characterization of a Forced Two-Dimensional, Weakly- Compressible Shear Layer

Experimental data are presented consisting of fluid mechanic and optical measurements made in a forced, two-dimensional, weakly-compressible subsonic shear layer. The measurements were made in the University of Notre Dame’s compressible shear-layer facility that mixes highand low-speed flows with speeds up to M = 1.0. The forcing was performed using voice-coil actuators mounted at the trailing edge of the splitter plate separating the highand low-speed flows at the inlet to the mixing section. Numerical results were also computed using a discrete-vortex, weakly-compressible computer code, and are used to interpret the experimental data. The experimental and numerical results are used to develop a simple yet effective feedforward adaptive-optic correction strategy for the optical aberrations imposed by the shear layer on a traversing laser beam.

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