Boundary layer associated with the Darcy-Brinkman-Boussinesq model for convection in porous media

► We study the infinite Prandtl-Darcy number Darcy-Brinkman-Boussinesq system. ► A boundary layer exists for the velocity field. ► Boundary layer thickness is proportional to the square root of the Brinkman-Darcy number. ► No boundary layer in the temperature field to the leading order. ► Results are mathematically rigorous.