Abstract: Based on multidisciplinary theory,a numerical model for solving ablation,denudation in a high temperature and high pressure environment is proposed.In this model,the Discrete Vortex Method（DVM） is used in simulate flow field and pressure distribution on the cylinder surface;a common used three-equations model under the thermal-chemical control mechanism is introduced for resolving the ablation loss after comparing with the results under the diffusion control mechanism;furthermore,the denudation loss is simplified by releasing a series particles on the cylinder surface at regular intervals,and a trajectory model is adopted for solving the particles motion.Codes are written and performed well for simulating the flow field,ablation loss and particles motion in a high temperature and high pressure blaster chamber.As results indicated,the flow filed with a lower Re number is basically the same as that in a non-ablation environment,whereas the differences are tremendous when a higher Re number is adopt;with a lower Re number,differences on ablation rate can be neglected whether flow field is considered,whereas the ablation rate is larger when the flow field is considered in a higher Re number;the vortex influenced the particles motion and distribution,which may change both the temperature distribution in the wake and the ablation rate on the cylinder surface;This model may offer numerical references to ablation experiments on thermal protection materials and prepare relative data for nonlinear analysis.