Numerical and Experimental Investigation of a Mechanically Ventilated Room - The Impact of Inlet Boundary Conditions on CFD Modelling of the Ventilation System -

Among the tools which serve to predict heat and mass transfer in a mechanically ventilated room, CFD is increasingly used. However, this type of tool needs a correct description of the boundary conditions, especially concerning the air inlet. The ventilation inlet is often geometrically complex and many models exist in order to simplify their equivalent boundary conditions included in CFD codes. Nevertheless, none of these simplified models can predict the correct behaviour of flows issuing, for example, from a T-pipe, a bend or a more complex ventilation system. The main idea is then to model a part of the ventilation system with the help of CFD and to impose boundary conditions on a fully developed flow section situated far from the inlet. The validation of this approach consists of the comparison of experimental and numerical data obtained for a mechanically ventilated room with and without thermal effects. This model has also been tested with more complex diffusers to show its broader scope.