Analytic Model and Numerical Simulation of Shock Wave Propagation into a Reentrant Corner

摘要

An analytical model is developed and numerical simulations are performed for shock wave propagation into a reentrant corner. The analytical and numerical results are compared with shock tube experiments performed in a 100 deg reentrant corner with a moderate strength (P sub 1/P sub 0 = 2.37, shock overpressure 137.9 kPa) incident shock and a weak (P sub 1/P sub 0 = 1.12, shock overpressure 12.41 kPa) incident shock. The analytical model provides an exact solution of the flow field if shock diffraction does not occur within the reentrant corner; it also provides an approximation to the peak vertex pressure which is comparable with experimental results if diffraction does occur. Both regular and Mach reflections are modeled. When the corner has finite length, an estimate of the duration of the peak vertex pressure is given. The numerical simulations are performed with the Eulerian hydrodynamic computer code DORF. In the DORF calculations, the reentrant corner is formed by a rigid smooth wall and a rigid stair-step wall. A detailed discussion of the stair-step construction and comparisons of the pressure distributions along these walls are included. Furthermore, the analytical and numerical pressure results for an infinitely long reentrant corner are compared.