Abstract: Local and average convection heat transfer coefficients were investigated inside the effusion hole in the impingement/ effusion cooling schemes, which have the hole number ratio of 1∶1, with different impingement wall andeffusion wall pressure drop distributions. The benchmark is the cooling air mass flow rate per unit pressure and areaof the high performance aeroengine. The results indicated that the pressure distribution has great influence on theheat transfer enhancement inside the effusion hole entrance ( x/ d < 4) . The mechanism of the enhanced heat transfer within the effusion hole entrance was explained using a CFD code. The correlation of the circumferential averageheat transfer enhancement coefficients was fitted based on the experiment data, which plays an important role forthe future heat transfer optimum of the impingement/ effusion double skin wall.

Key words: gas turbine engine, combustion chamber, film coolin g, convection heat transfer, hole entrance