Flows produced by a forced plume in a ventilated enclosure

The purpose of this communication is to present new results concerning velocity fields within the enclosure and close to the openings of a ventilated room with a buoyant turbulent 2D plume originating at its bottom. The enclosure is ventilated through lower and upper openings located on the two opposed vertical walls and separated by a vertical distance H. Depending on the enclosure geometry and forced plume characteristics, this situation can drive different kinds of flow regimes (blocked, intermediate and displacement) through the lower and upper openings. Three flow regimes are successively studied by adjusting a new densitometric Froude number related to the source flow rate, the densities inside and outside the enclosure and the area of the upper opening. When , buoyancy forces are larger than inertial forces and the displacement regime is then observed. In cases where inertial forces are larger than buoyancy forces then and the intermediate or blocked regimes are involved and forced convection dominates. Results of velocity fields measured by 2D PIV in the mid plane of the enclosure are presented for the three regimes. By using velocity and temperature measurements performed at the nozzle and at the lower and upper openings in seven x?y planes located at z/l=0, ?1/8, ?1/4, ?3/8, balance of mass flow rate is verified and heat loss by conduction through the walls is evaluated for the three studied regimes.