Effects of Counterflow Jet on the Performance of a Generic Rocket

Speaker: Semih Olcmen, University of Alabama
September 29, 2021

Presentation

Abstract

Effects of the counterflow-jet on the drag of a generic missile shape has been investigated at Mach numbers ranging from 4 to 9. Computational results were obtained for flight at 40,000 ft altitude. The nose shape used had a radius to length ratio (aspect ratio) of 0.5, which was previously determined to be the missile nose shape that would penetrate the most to geometrical targets. The nose shape reduces the aerodynamic drag by about %36 in comparison to tangent-ogive nose shaped missile, and the counterflow-jet reduces the nose drag an additional %22, resulting in about a total of %50 drag reduction. In addition, the nose shape and the counterflow jet result in average missile surface temperature reduction ranging 400 to 1000 K with increasing flight Mach number. The technology may reduce the need for unique materials for hypersonic missiles.

Biography

Semih Olcmen is a professor at the University of Alabama, Aerospace Engineering and Mechanics department. He has been in Alabama for the last 19 years and graduated more than 40 Masters, and Ph.D. students. He has published more than 100 journal and conference papers. He holds a patent for a unique laser-Doppler velocimetry probe. His research areas include both experimental and computational fluid mechanics both in subsonic and supersonic flows. His latest areas of research focus on missile nose optimization, missile drag reduction, weapons bay acoustics, shockwave/boundary layer interaction, and artificial intelligence for inverse design of subsonic airfoils.

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