Flow and heat transfer characteristics of slot jet impingement to a cylindrical convex surface

The flow and heat transfer characteristics of slot jet impingement to a cylindrical convex surface were investigated by the numerical method.Suitable turbulence models were determined by comparing experimental data with the numerical results of four turbulence models.The flow structure,boundary layer separation and wall heat transfer enhancement characteristics of slot jet impingement to a cylindrical convex surface were discussed on the basis of the pressure gradient distribution.The results show that RNG k-ε and Realizable k-ε models are suitable to predict.The slot jet impinges to a cylindrical convex surface,the gas flows along the convex surface,the velocity decreases and the boundary layer separation appears downstream.The dimensionless adverse pressure gradient increases with the dimensionless radius of curvature(D/B) decreasing,leading to an earlier boundary layer separation.Nu in the stagnation region can be enhanced by decreasing D/B.However D/B has almost no effect on heat transfer in the downstream flow.The pressure gradient is a key factor in affecting the heat transfer distribution in slot jet impingement to a cylindrical convex surface.