A coupled NS-DSMC method applied to supersonic molecular beam and experimental validation

In this paper, experimental and numerical studies are conducted on supersonic molecular beam injection (SMBI) for fusion devices based on steady-state assumption. To explore the characteristics of SMBI from continuous to rarefied flow, the flow information is predicted by solving the Navier-Stokes (NS) equation based CFD method and direct simulation Monte Carlo (DSMC) method. To verify the coupled NS-DSMC method, a flow measurement apparatus platform is designed and constructed. A moveable full-range vacuum gauge with Pitot probe in the vacuum chamber is employed to measure the spatial distribution of the beam pressure signal. The simulation results are converted into Pitot pressure, corrected for rarefaction effect and compared with the experimental data. It is observed that the experimental results are consistent with the simulation results. This study provides technical support for the accurate prediction of SMBI flow characteristics and optimization of the SMBI systems.