Mixed convection in a horizontal rectangular duct heated from below

This paper deals with a mixed convection flow in a horizontal rectangular duct of transversal aspect ratio close to two, uniformly heated from below and thermally insulated elsewhere. The working fluid is water (Pr = 6) and the Reynolds number associated with the main flow is small (Re = 20). The heat flux supplied to the wall induces a secondary flow which manifests itself through natural convective rolls. This study has been conducted simultaneously via two ways: an experimental approach which enables us to investigate a large range of the two main control parameters (Reynolds and Rayleigh numbers) and a numerical analysis which permits us to obtain detailed local and global descriptions of the fluid flow and heat transfer throughout the whole computational domain. Copyright , Manchester University Press.