Gaussian distribution models of voltage wave form of MID of TEMP Ⅱ accelerator and IPIB density near the MID focus region have been built according to the results of experiments. The energy deposited in the target were calculated by using Monte Carlo method based on these models. Then we use them as thermal sources in hydrodynamic equations, and simulate the evolution process of pressure transported in target based on different kinds of state equations of material. The pressure evolution profile of plasma generated by IPIB irradiated Al target with high enough beam energy density has also been calculated by combining the ideal gas model of plasma and HD equations.