Numerical Investigation of Gas Injection in Reducing Skin Friction Drag in under water surface of oil tank

A two -dimensional two phase computational fluid dynamcis CFD model of micro bubble laden flow over a flat plate was used. The model consisted of reynolds -averaged navier stoked RANS transport equations , a standard k-e turbulence model and a convection diffusion species transport model. performance of the model was validated with available experimental data and numerical simulations of more advanced multiphase - fluid model. in this study drag reduction by Co2 injection in to turbulent boundary layer was investigated also variation of turbulent parameters in the model was evaluated . the study indicated that simple mixture density ratio variation effect plays one of the major roles in the micro bubble drag reduction phenomenon.