Flow Induced by Thermal Stress in Rarefied Gas

A new kind of mechanism which induces a flow around a solid body in a slightly rarefied gas is proposed. In order to demonstrate the flow induced by this mechanism the behavior of gas around a sphere with a constant temperature which is placed in an infinite expanse of gas at rest with a uniform temperature gradient is investigated on the basis of the asymptotic theory for a slightly rarefied gas. A flow with magnitude of the order of the Knudsen number squared is induced from the hotter to the colder region. The sphere is subject to a force in the direction of the given temperature gradient.