Abstract
This study employed the use of experimental data of film cooling effectiveness using corrugation film cooling hole. Effects of blowing ratio in conjunction with twisted angles (0°, 90°, 180°, 270° and 360°) were also investigated. Recently, the utilization a vortices in enhancing thermal transfers is becoming increasingly attractive as a result of its dual advantages including its surfaces that are extended, turbulent twisted holes as well as coarseness. Results of enhancement in the effectiveness ranging from 1.2–2.2 times those from conventional smooth film cooling holes with significantly increased coefficient of thermal transfer ranging from 1.50 to 2.70 times those of the conventional film cooling holes with smooth surfaces. Both the numerical and the experimental analysis of the effectiveness of film cooling were authenticated by results from pervious related studies. The authors found and concluded thus, effectiveness of twisted film cooling holes at rectangular spiral corrugation shape was higher in comparison to holes with cylindrical shape. The effectiveness of film cooling for the twisted holes were observed to be hugely influenced by inclination angle between the main and the secondary holes of the film cooling hole antivortex.
