An improved BGK-type collision-term model for Direct Simulation Monte Carlo (DSMC) methods
نویسندگان
چکیده
The BGK and BGKC (Bhatnagar, Gross, Krook, and Cercignani) collision-term models for the Boltzmann equation are compared to the more rigorous variable-hard-sphere (VHS) collision-term model of Bird. The BGKC model is based on the well-known BGK model but uses an ellipsoidal statistical (ES) distribution instead of a Maxwellian distribution so as to incorporate both viscous effects and heat conduction accurately. The Direct Simulation Monte Carlo (DSMC) method of Bird is used with the BGK, BGKC, and VHS collision terms to simulate supersonic flow of a monatomic gas over a wedge. The BGKC results are consistently in good agreement with the VHS results, whereas the BGK results show systematic differences.
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