Optimizations and applications in large-scale scenes of Monte Carlo geometry conversion code CMGC  

作　　者：Xin Wang Ling-Yu Zhang Xue-Ming Shi Zhen Wu Jun-Li Li Gui-Ming Qin Yuan-Guang Fu 

机构地区：[1]CAEP Software Center for High Performance Numerical Simulation,Beijing 100088,China [2]Institute of Applied Physics and Computational Mathematics,Beijing 100088,China [3]Department of Engineering Physics,Tsinghua University,Beijing 100084,China

出　　处：《Nuclear Science and Techniques》2025年第4期220-232,共13页核技术(英文)

基　　金：supported by the National Natural Science Foundation of China(No.U23B2067);Innovation Program of CAEP(No.CX20210045)。

摘　　要：In response to the demand for rapid geometric modeling in Monte Carlo radiation transportation calculations for large-scale and complex geometric scenes,functional improvements,and algorithm optimizations were performed using CAD-to-Monte Carlo geometry conversion(CMGC)code.Boundary representation(BRep)to constructive solid geometry(CSG)conversion and visual CSG modeling were combined to address the problem of non-convertible geometries such as spline surfaces.The splitting surface assessment method in BRep-to-CSG conversion was optimized to reduce the number of Boolean operations using an Open Cascade.This,in turn,reduced the probability of CMGC conversion failure.The auxiliary surface generation algorithm was optimized to prevent the generation of redundant auxiliary surfaces that cause an excessive decomposition of CAD geometry solids.These optimizations enhanced the usability and stability of the CMGC model conversion.CMGC was applied successfully to the JMCT transportation calculations for the conceptual designs of five China Fusion Engineering Test Reactor(CFETR)blankets.The rapid replacement of different blanket schemes was achieved based on the baseline CFETR model.The geometric solid number of blankets ranged from hundreds to tens of thousands.The correctness of the converted CFETR models using CMGC was verified through comparisons with the MCNP calculation results.The CMGC supported radiation field evaluations for a large urban scene and detailed ship scene.This enabled the rapid conversion of CAD models with thousands of geometric solids into Monte Carlo CSG models.An analysis of the JMCT transportation simulation results further demonstrated the accuracy and effectiveness of the CMGC.

关 键 词：Monte Carlo CAD BRep to CSG CMGC 

分 类 号：TL3[核科学技术—核技术及应用]