Effect of Coolant Jet Direction on Film Cooling Behavior

  • Asst. Prof. Dr. Muwafaq Shyaa Alwan Al-Iraqia University, Collage of Engineering, Baghdad, Iraq
  • Asst. Prof. Dr. Amer M. Al-Dabagh University of Technology, Baghdad, Iraq
  • Asst. Lect. Omar Hassan Hameed Al-Iraqia University, Collage of Engineering, Baghdad, Iraq
الكلمات المفتاحية: Film cooling, Jet direction, Kidney vortex, horseshow vortex


Numerical investigations were done on a flat plate in order to predict the flow behavior, vortex type, and vortex generated at holes and holes downstream area, and the interaction between hot mainstream and coolant jet. Two type of singular coolant air jet were studied; the first jet hole inclined at 30º in the direction of hot air stream. The second holes are lying in the opposite direction at 30º. All simulation were conducted at blowing ratio of 0.5 and 1.5, the diameter of cooling hole is 4mm. The commercial CFD software FLUENT with standard turbulent models was applied. The results showed that there are two large vortices have been detected, large counter rotating vortex pair generated from the hole rims and horseshoe vortices, both vortices have major effects on cooling performance. The results also showed that the reverse flow from backward injection hole creates pair of vortex similar to the kidney vortex created from forward injection hole, but in a plane parallel to the main stream.   


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