Simulation study of effective pumping speed of divertor pumping system for CFETR with COMSOL Multiphysics

•Simulation of neutral gas flow in the CFETR divertor pumping system using COMSOL multiphysics.•The slip boundary conditions modified navier-stokes equation (N-S+slip) method and the angular coefficient (AC) method are used.•Throughput, flow conductance and effective pumping speed are calculated.•Comparison of the simulation results with the DSMC and TPMC methods indicates very good agreement.•The computational efficiency of different simulation methods is compared.