This paper presents the numerical results of a new film cooling design that combines the Backward injection Hole with Barchan-dune shaped shells (BH-BDS). The performance of this novel design in improving the film cooling effectiveness is compared to other configurations, Forward injection (FH), Backward injection (BH) and the configuration that combines the forward injection with Barchan-dune shaped shells (FH-BDS). Three blowing ratios are considered in this paper, M=0.5, 1.0 and 1.5. The air coolant was injected through holes inclined at 35° and 155° for forward and backward cases respectively. The lateral averaged film cooling effectiveness and the distribution of adiabatic film cooling efficiency are studied using commercial software ANSYS- CFX. Three turbulence models, including the k-? SST, the standard k-e and RNG k- e were examined in the present investigation. It was found that the RNG k- e model is closer to the experimental data. The main result of this study reveals that the presence of upstream dune shaped shells with backward hole yield a better film cooling effectiveness especially at higher blowing ratios (M=1).