In the present Study, effects on beat transfer of different type of extended surface placed oil a flat plate oil two dimensional rectangular cross-sections are investigated with conjugated heat transfer approach. Surface and air inlet temperature were fixed for the condition of turbulent flow. Effect of Reynolds number on heat transfer coefficient was investigated for triangular rib g geometry. Three type of extended surface geometries were used which are circular, rectangular and triangular in the present study. For these geometries, temperature Contours and local Nusselt number were obtained for Re = 500. Triangular extended geometry with groove was also investigated and temperature contour and local Nusselt number were shown.