Abstract: The partial differential conservation equations for mass,momentum and energy are applied by adopting the compressible fluid model forthe explosion flow field. Based on the Eulerian algorithm of multi-materialin cell (MMIC), the operator splitting scheme is used, and the movinginterface is treated by volume ratio method. The development of the shockwave near the explosion source and in the explosion field caused bythree-dimensional air explosion are simulated using three-dimensionalnumerical simulation code MMIC3D compiled by authors. The formation andchange of the flow field around the corner wall are studied. Furthermore theeffects of the explosion shock wave are analyzed and compared with theempirical formula because of different locations and different shapes of theprotective wall. The simulation results turn out to be in full agreementwith the principle of physics. It also indicates that the model andalgorithm presented in this paper are proper, thus the numerical simulationcan be used for engineering design of decompression facilities.