A numerical analysis of transpiration cooling as an air cooling mechanism

The present study is focused on investigation of heat transfer from a porous plate by cooling of air with transpiration cooling. Effects of Reynolds number of hot gas stream, inlet temperature of air and mass flow rate of water on local wall temperature and cooling effectiveness of porous flat plate and efficiency of the system inside a rectangular channel with air as a hot gas stream and water as a coolant were investigated numerically. Increasing Reynolds number causes an increase on surface temperature and a decrease on cooling effectiveness of porous plate and efficiency of the system. Increasing of air inlet temperature does not cause a significant increase on cooling efficiency of the system. An increase of water flow rate causes a decrease on surface temperature and an increase on effectiveness of porous plate and cooling efficiency of the system. Numerical results prepared by RNG k-epsilon turbulence model have a good approximation and show a similar flow characteristic with experimental results.