Numerical investigation of shock wave attenuation in channels using water obstacles

Here, short duration direct numerical simulations of shock water cylinder interaction in a two-dimensional channel are conducted to study shock wave attenuation at time scales smaller than the cylinder convection time. Four different cylinder configurations, i.e., 1 x 1, 2 x 2, 3 x 3, and 4 x 4, are considered, where the total volume of water is kept constant throughout all the cases. Meanwhile, the incident shock Mach number was varied from 1.1 to 1.4. The physical motion of the water cylinders is quantitatively studied. Results show that the center-of-mass velocity increases faster for the cases with more cylinders. In the early stage of breakup, the transfer rate of kinetic energy from the shock-induced flow to the water cylinders increases as the number of cylinders increases. Further, comparing the cases of different incident shock Mach numbers, higher center-of-mass velocity is induced for the cases of lower incident shock Mach numbers. Moreover, the pressure and impulse changes upstream and downstream of the cylinder matrices are tracked as a quantitative evaluation of the shock attenuation.