Dimensional analysis is an important research method to solve the problems of science and engineering and is commonly used. It can be used to guide the arrangement of experiments and the processing of experimental data. Dimensional analysis can be used to have a qualitative understanding of the problem before solving a problem and determine the physical laws of a phenomenon or verify the correctness of physical relationship. The conversion of physical quantities is often encountered between the physical system and numerical system (or experiment system) in the numerical simulation and modeling experiments, and can be solved effectively using dimensional analysis method.