Numerical Simulation on the Flow Fields Downstream Nozzles with Tabs by Modified Turbulent Model

摘要

Firstly, the flow fields downstream one axisymmetric nozzles and a nozzle with four tabs were simulated with four different turbulent models, and the results were compared with experimental data. Then the flow fields downstream nozzles with tabs of varied orientation angles were predicted for different orientation angles of the tabs while the projected blockage of tabs was kept unchanged. The predictions were also compared with that of the nozzle without tabs. The decrease of potential core length was remarkable when tabs were affixed. As the orientation angle increased, the potential core length decreased firstly and then increased. The streamwise vortices strength increased straightly with the orientation angle. Both entrainment gain and thrust losses of the nozzles decreased as the orientation angle increased.