The Effect of Size and Location of a Heating Source on the Buoyant Flow in a Heated Space

Abstract

A numerical study of two-dimensional turbulent buoyant recirculating flowswithin a heated space is presented. The study involves the solution of elliptic partialdifferential equations for the conservation of mass, momentum, energy, turbulenceenergy and its dissipation rate. These equations were solved together with algebraicexpressions for the turbulent viscosity and heat diffusivity in a finite difference form.The simulations of the turbulent buoyant flow within the space were undertakenusing two principle geometrical arrangements (A & B) of the room with differentlocations and sizes of a heating source (b/h=0.08, 0.28, and 0.5 for geometry A andb/h=0.75, 1.45, and 6.0 for geometry B). The study demonstrates that for a thermalcomfort conditions in the space the location and size of the heating source are of greatimportance. When the heating source is located in the middle of the floor it is found togenerate a high velocity air stream resulted from vortices produce a local thermaldiscomfort in the occupation zone. On the other hand its location under a coldwindow offsets the losses in heat and avoiding the form of the high velocity airstreams in the occupation zone. The size of the heating source is also found toinfluence the occupation zone condition through the effect on the heat transfer rateinside the conditioned space.