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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 more 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 3-D 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 ([epsilon] = 1, 10, and 100) were considered. The interaction at [epsilon] = 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.

Laser energy deposition in quiescent air has been studied experimentally and numerically. The study is focused on the gasdynamic effects of the laser energy spot on the flow structure. A Gaussian profile for initial temperature distribution is proposed to model the energy spot assuming the density is initially uniform. A filtered Rayleigh scattering technique has been used for obtaining the experimental results. These consisted of flow visualization of the blast wave, and simultaneous pressure, temperature, and velocity measurements. Good agreement has been achieved between numerical and experimental results for shock radius vs time. The comparison of computed and experimental density, pressure, temperature, and velocity outside the laser spot show good agreement as well.

The three-dimensional interaction between shock waves and turbulent boundary layers are studied through numerical analysis. Crossing shock experiments are conducted wherein simulated flows at a freestream Mach number are investigated. The Reynolds-averaged Navier-Stokes equations are then employed in conjunction with the Baldwin-Lomax model to establish the relations between the fin-generated shock waves and boundary layer. Results show that the shock wave-boundary layer interaction produces counter-rotating vortical structures.

The mean flowfield of a three-dimensional supersonic turbulent boundary layer, generated by a 20-deg isentropic compression, was studied experimentally and numerically. Experimental data include surface flow visualization, wall static pressures, surface skin friction, and surveys of pitot pressures, yaw angles, and static pressures. Earlier published comparisons with data computed from the three-dimensional Reynolds-averaged compressible Navier-Stokes equations with an algebraic turbulence eddy viscosity closure show good agreement within experimental and computational uncertainties. Focus of the current work is the presentation of different scalings of the experimental data and the proposal of a new model for the mean flowfield scaling. Comparison to a subsonic three-dimensional boundary layer is made for this new scaling law.