Numerical Simulations Of Jet In Cross-flow On Flat Plate

As a common mixture of two kinds of fluid in reality, Jet in Cross-flow(JICF) has both important value of theoretical research as well as special significance of engineering. There are several commonly used numerical methods for the numerical simulation study on JICF. The accuracy of the methods forecasting for the flow field of JICF are compared and evaluated in the thesis.RANS and two unsteady numerical calculation methods, LES and DES, are adopted to study on the flow field of JICF under the condition of blowing ratio of 0.5 and 1.5. The simulation results show that, four kinds of turbulence models and two kinds of the unsteady numerical simulation methods can accurately predict the flow field of JICF, while S - A model has a better performance under the condition of low blowing ratio. Meanwhile under the condition of high blowing ratio, four kinds of turbulence models and two kinds of the unsteady numerical simulation methods can properly predict the flow field of JICF, and K-ω model is the best among them. Compared with the RANS models, LES and DES do not have advantages in prediction accuracy.Aimed at the symmetry structure of wake region downstream of the jet hole, the LES research of JICF is carried out under the blowing ratio of 0.5 and 1.0 with a mesh about 5.6 million. Through this, the changing of flow field downstream jet hole with time is observed. The critical blowing ratio proposed by other scholars is proven to be unreal by LES method finally.