We discuss the application of front tracking to the simulation of shock reeec-tions and shock accelerated interfaces. Some key features of the front tracking method are the elimination of numerical diiusion and the reduction of wall heating. In computations of the regular Mach reeection of a shock at an oblique ramp, we see enhanced resolution of the primary waves in the interaction. In addition, tracking allows very precise measurements to be made of the states and location of the Mach triple point. Our computations of the growth rate of a Richtmyer-Meshkov unstable interface are the rst numerical results that are in quantitative agreement with experimental results of a shocked air-SF 6 interface. Previous attempts to model the growth rate of the instability have produced values that are almost twice that of the experimental measurements. Moreover, the failure of the impulsive model, and the linear theory from which it is derived, to model experiments correctly is understood in terms of time limits on the validity of the linear model. In this article we present results of simulations using front tracking combined with a second order Godunov nite diierence method. Two classes of problems are discussed, the oblique reeection of shock waves at ramps, and the computation of the instability growth rate of a perturbed, shock-accelerated interface. Our code achieves excellent resolution of the simulated ows, even on the relatively coarse grids used here. In both cases our computed results are shown to be in excellent agreement with experiments. Indeed, we present computations of the Richtmyer-Meshkov instability that for the rst time agree with experimentally measured growth rates of interface perturbations. The ramp reeection simulations model the interaction of a planar shock wave with an oblique wall. We are interested in determining the structure of the reeection process for ramp angles that are very close to the mechanical equilibrium condition for bifurcation to regular reeection, as deened by the coincidence of regular and Mach reeection. The use of front tracking allows us to conduct numerical experiments that are extremely close to this point.

We discuss the use of front tracking to simulate shock reflections and shock-accelerated interfaces. Our simulations of regular Mach reflection show enhanced resolution of the primary waves in the interaction, and our computations of the growth rate of a Richtmyer-Meshkov unstable interface are the first numerical results that are in quantitative agreement with experiments on a shocked air-SF6 interface. Previous computations of the growth rate of the instability produced values that were almost twice those found in experiments.