On the Validity of the Relaxation Time Approximation for Macroscopic Transport Models
نویسندگان
چکیده
Although many doubts have been raised concerning its accuracy, the macroscopic relaxation time approximation is often used to approximate the weighted averages of the collision integral. More accurate approaches based on expansions of the distribution function deliver better results. Unfortunately these models depend on the fluxes of the system which causes a coupling of the flux relations. Our results indicate that this coupling requires accurate models for the energy tensors to obtain an overall quality improvement in the resulting transport model.
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