Computational Fluid Dynamics Analysis of Turbulent Jet

Abstract

The impinging jet with turbulent flow is studied as it has a wide industrial applications and the presence of turbulence in a small confined domain causes complexity in the flow field. These abrupt changes in the flow show characteristics like re-circulation, strong streamline curvature and development of boundary layer. The presence of such characteristics in the flow enhances the heat and mass transfer properties in a very small domain and it has lots of uses in industry. A platform of ANSYS-fluent is used to analyze and study the process of heat transfer, the factors affecting it and the means for further enhancement. The effect of parameters like nozzle-to-plate distance, Reynolds number, Prandtl number, thermal conductivity, impingement plate thickness and the orientation of jet with respect to impingement surface has been studied. The current study focuses on the validation of the selected model, oblique nozzle orientation with the impingement plate and comparing it with an orthogonal jet. The analysis is done on the basis of RANS turbulence model namely k- ϵ turbulence model. The observation of velocity contour for the components of velocity in X and Y direction, stagnation pressure contour, turbulent kinetic energy contour and turbulence dissipation contour is made. Also the XY - plots of U-velocity, Stagnation pressure, Nusselt number, Wall heat flux, Wall shear and temperature over the interface surface us plotted. Form the following results the optimum angle of the inclination of jet is found to be θ =15 ° and for both orthogonal and oblique jet optimum nozzle-to-plate spacing is found to be H = 40 mm at constant temperature boundary condition and H = 20 mm for constant heat flux boundary condition at the impingement plate. The oblique jet enhances the average heat transfer by 8.2 % compared to oblique jet.