Numerical modelling of energy efficient exhaust orifices and hoods in ventilation and air conditioning systems in buildings and facilities of thermal power plants

Abstract

Abstract The paper presents the results of numerical simulation of energy-efficient inlet parts of exhaust ventilation systems in the form of the last side orifice and an exhaust hood. The profiling of the inlet sharp edges is used, which is made according to the outlines of the vortex zones that generates when the flow is separated at this edges. For this, the non-profiled geometry of the exhaust orifices is first modelled, where the outlines of the vortex zones are determining. Then a numerical model with profiling is created and the energy losses of such an improved shaped elements is determined. A significant reduction in pressure loss has been obtained: for the exhaust hood more than 40% and 30% for the last side orifice.