HIGH PERFORMANCE NUMERICAL SIMULATION METHOD FOR NON-POINT SOURCE POLLUTION TRANSFER PROCESS

Efficient and high-precision simulation of the process of non-point source pollution and mastering the law of non-point source pollution is one of the most direct and effective ways to study non-point source pollution, and also an effective way to manage and control non-point source pollution. Based on this, this paper proposed a numerical model that fully coupled two-dimensional hydro-hydrodynamic and pollutant transport processes. It used the second-order Godunov format finite volume method to solve the problem, and used GPU acceleration technology to improve computing efficiency. The results showed that, under ideal conditions, the average relative error between the numerical and analytical solutions was 2.5%. The transport processes of urban surface source pollution and agricultural non-point source pollution with different areas and accuracy were simulated, and the results showed that the transport laws of the two were consistent with the actual physical process. The total simulation time was 7200 s. The simulation of urban surface source pollution took only 186 s; the simulation of agricultural non-point source pollution took 1169 s, and the calculation efficiency was significantly improved. In summary, the GAST model could not only achieve high-precision simulation of different underlying surface source pollution simulations, but also significantly improve the simulation efficiency, and provide basic support for future non-point source pollution control and prevention.