Fluid structure interaction with a finite rate chemistry model for simulation of gaseous detonation metal-forming

Abstract

Numerical simulation of metal-forming by gaseous detonation in a stoichiometric mixture of H2-O2 is performed in this paper, utilizing the Space-Time Conservation Element and Solution Element (CESE) method. We employ the CESE method to solve the reacting flow equations, including realistic finite-rate chemistry model. The detonation mechanism is considered by a detailed mechanism of the seven species and sixteen reactions for H2-O2 mixture. The fluid-structure interface treatments smoothly handle between detonation wave and work piece by using the immersed boundary method (IBM). To accurately predict the behavior of the work piece, the fluid (CESE) solver was coupled with the LS-DYNA® FEM structural solver.The fluid solver applies the fluid pressure on the structural elements as external boundary conditions and feeds back the displacements and velocity of the interface from the structural solver as its new boundary, while the chemistry solver preparing all source terms in the conservation equation for fluid solver.Our purpose is to evaluate the accuracy of CESE-IBM FSI method to handle the gaseous detonation metal-forming, which is a very complex FSI problem with chemistry. After a description of CESE-IBM FSI method, finite-rate chemistry model and experimental test set-up, a comparison is performed through the detonation characteristics, midpoint deflection of the work piece, and effect of initial pressure and temperature of the gas mixture. A good agreement is obtained between numerical results and empirical data.