NUMERICAL INVESTIGATION OF TURBULENT PLUMES IN BOTH AMBIENT AND STRATIFIED SURROUNDINGS

Ventilation displacement systems have, during the last ten years, beco me more and more popular. In these systems cool air is supplied to the room, and the air is heated by heat sources. The rising air above the se heat sources is of paramount importance to the behaviour of the ven tilation displacement systems. In the present work the turbulent flow in plumes is studied numerically, using finite volume methods. The sta ndard k-epsilon model was found to underpredict the spreading of the p lumes, and it was thus modified in two ways so as to predict spreading rates in agreement with experiments. We present a comprehensive compa rison between predictions and experiments including spreading rates, v elocity and temperature profiles, and turbulent shear stresses. The vo lume flow rate versus the vertical distance from the plume is also pre sented. Good agreement between predictions and experiments is obtained .