To investigate the geometrical performance of laminated film cooling configurations

the surface temperature distributions of three different specimens with true size of gas turbine components were measured by an infrared thermal imaging system.Experiments were carried out in the hot gas wind tunnel of University of Science and Technology of China(USTC).To describe the overall cooling effect contributed by coolant impingement

heat conduction and convection

an algorithm of digital imaging signal was used

and the two-dimensional temperature drops from initial wall to cooled wall were directly obtained.Through comparisons of the cooling performance of these three specimens

the effects of the number and diameter of columnar ribs

the angle of film holes

the Reynolds number and Nusselt number of free stream on the overall cooling effectiveness were discussed.