The Experimental Study of Flow Control Using Laser Energy Deposition around High Speed Propulsion System

Laser energy deposition is one of the effective methods to control high speed flow around the high speed intake. LED (Laser Energy Deposition) is able to control flow rapidly and does not need a heavy mechanical part. experimental investigation was conducted to examine the effect of a pulsed Nd:YAG laser energy deposition on the shock structures in supersonic/hypersonic flow and quiescent air. The effect of the laser energy and pressure in the blast wave generation were also investigated. At results, the strength of plasma and blast wave becomes stronger as pressure or laser energy increase. And the breakdown threshold of air by laser energy deposition is 0. 015 bar at 508 mJ laser energy, the blast wave threshold generation in air by laser energy deposition is 0. 100 bar at same laser energy. As qualitative analysis, schlieren images are also obtained. After the series of experiments, the effect of LED on high speed flow around the shock shock interaction created by a wedge and blunt body. By LED, the structure of shock - shock interaction was collapsed momentary and the pressure of the stagnation point was fluctuated while interference of wave.