How different Vlasov Equation with Drift diffusion equation physically ?

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Timofey Golubev

Hello,

The Vlasov equation is similar to the Boltzmann transport equation, but with the collision term equal to zero. The Drift diffusion equation can be derived from Boltzmann equation by using the relaxation time approximation for the collision term and then taking the 1st moment (i.e. by multiplying by velocity v and integrating over dv). The hydrodynamics equations can be derived by taking higher order moments. You can look up "method of moments" for more details.

Kyunghwan Oh

Thank you for your answer. :)