CAD/CSG dual-layer hybrid geometric Monte Carlo particle transport method

Abstract

The CAD and CSG hybrid modeling for the Monte Carlo particle transport simulation improves the geometric accuracy and calculation efficiency. We propose a CAD/CSG dual-layer hybrid geometric Monte Carlo particle transport method, which divides the geometry into two layers, the CAD layer and the CSG layer, and overlaps them to build up the hybrid geometric model for particle transport simulation. The new method’s accuracy is verified to prove that the new method has the same accuracy as that of CSG modeling alone or CAD modeling alone. The efficiency advantages of the new method are tested to know that increasing the number of CSG surfaces and reducing the number of CAD surfaces improve the efficiency. The efficiency advantages begin to appear compared to CAD modeling alone when the ratio of the number of CSG surfaces to the number of CAD surfaces reaches 4:6, about an improvement of 10%. Increasing the proportion of CSG surfaces improves the efficiency advantages, and smaller geometric tolerances accentuate the efficiency advantage.