The problem of the non-isothermal flat cavity filling by a Newtonian fluid with simultaneous impregnation of a porous layer is considered. The flow in a cavity is described by the non-inertial Navier-Stokes equations, in a porous layer by the Darcy law, and in the region adjacent to the boundary of the liquid – porous layer by the Brinkman equation. Viscosity is considered temperature dependent. Temperature fields in the channel region and the permeable layer interconnected via conjugate boundary conditions of the fourth kind.