A numerical study was conducted to understand the effect of a single laser pulse on a normal shock and shock boundary layer interaction. The goal is to examine the capability of a pulsed laser energy deposition to momentarily move a normal (terminal) shock upstream in a mixed-compression inlet so as to counteract the effect of a disturbance that would move the normal shock downstream. Two numerical models were used. The perfect gas model for energy pulse was developed at Rutgers University, and the commercial software GASPex was used as the flow solver. The real gas model was developed at the University of Minnesota. The research was conducted in two phases. First, the 3D interaction of a laser pulse with an isolated normal shock at Mach 2 was examined using the perfect gas and real gas models. A detailed comparison of the computed flowfields indicates that the principal details of the interaction are accurately predicted by the perfect gas model. Second, the perfect gas model was used to simulate the 2-D interaction of a laser pulse with a normal shock including the effects of the interaction of the shock wave with a turbulent boundary layer. Three different dimensionless energy levels (e = 1,10, and 100) were considered. The interaction at f = 100 demonstrated a prominent upstream movement of the normal shock and a significant though temporary increase in the length of the separation region due to interaction of the compression wave (induced by the energy spot) with the separated boundary layer.
Bibliographical noteFunding Information:
This research is supported by the U.S. Air Force Office of Scientific Research (AFOSR) under Grant No. FA9550-04-1-0177 monitored by John Schmisseur. The 3-D computations were performed at Rutgers University and the University of Minnesota, and the 2-D computations were performed at Rutgers University and at the National Center for Supercomputing Applications (NCSA). The authors would like to thank Ramesh Balakrishnan for his assistance with the computations at NCSA.