HEAT-TRANSPORT IN A DILUTE GAS UNDER UNIFORM SHEAR-FLOW

Energy transport in a dilute gas under a steady shear flow state is analyzed. The physical situation is such that a linear profile of the flow velocity coexists with a weak thermal gradient. The shear rate is arbitrary so that the heat flux is affected by the presence of the shear flow. The results are obtained from the Boltzmann equation for Maxwell molecules. By performing an expansion around the shear flow state, an explicit expression for the shear-rate-dependent thermal conductivity tensor is derived. A comparison with previous results obtained from the Bhatnagar-Cross-Krook kinetic model is carried out. © 1995 The American Physical Society.