Mathematical modeling rarefied gas flow in a rectangular channel with an inner cylindrical element

The article proposes method of solving the problem of heat and mass transfer in a long rectangular channel with an inner cylindrical element. A rarefied gas flow trough cross section is studied on the basis of kinetic equation in the free molecular. Diffuse reflection model for the boundary condition at the channel walls is used. The expression for the mass flux is obtained as a linear function of a pressure gradient supported in the channel.