Improvement in Optical Environment over Turrets with Flat Window Using Passive Flow Control
نویسندگان
چکیده
Several pin configurations were tested in an attempt to improve the aero-optical environment at large look-back angles over a cylindrical turret with a flat window. When small-diameter, tall pins were placed upstream of the cylindrical turret they created a partial blockage and formed a second shear layer. The second shear layer reduced the turbulent intensity of the main shear layer, with a reduction in the overall levels of aero-optical aberration by as much as 20% over a range of elevation angles between 120 and 145 degrees. A simple model is presented proposing a physical mechanism for the aero-optical reduction.
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