Interaction of a surface mounted hot body with a turbulent boundary-layer

The main objective of this study is to understand the flow structure close to the roughness elements over which a thick turbulent boundary-layer is developed and the way it interacts with a surface mounted hot cube having in mind possible applications to the thermal interaction of a building located in a urban area under light sind or calm atmospheric conditions. The whole structure of the turbulent boundary-layer is studied in what concerns mean flow field, turbulent intensity and shear stress profiles. Boundary-layer integral parameters are calculated and their along wind development is studied, in a relative wide range of different roughnesses. Different flow conditions are used, ranging from natural to forced convection. Particular attention is given to mixed convection situations typical of a wide variety of practical problems such as building environment and industrial equipment. The influence of wind incidence is also studied. The study comprises also a numerical simulation, using a three-dimensional computer code based on the k-epsilon two equation turbulence model. Numerical results are compared with experimental ones in what concerns the development of the turbulent boundary layer itself and the way it interacts with the heated bluff body. (C) 1998 Elsevier Science Ltd. All rights reserved.