Predictions of variable energy blast waves

Abstract

Results from a numerical investigation of spherical blast waves with time-dependent energy deposition are reported. A description of the dynamics of these variable-energy blast waves is obtained from the solution of a set of nonlinear, partial differential equations that represent the conservation of mass, momentum, and energy in a spherically symmetric flowfield. For the current application, a finite-differe nce formulation of the governing equations in Lagrangian coordinates was selected, and the time-dependent nature of energy deposited was restricted to a power law input with positive exponent. Numerical calculations were performed during the energy deposition period for linear energy deposition. Propagation and decay of the shock front as well as internal flowfield properties have been obtained for these blast waves in air and chloroform. Results presented include shock front trajectory and Mach number, and radial density and pressure profiles for linear energy deposition in air for the spherically symmetric case.