Total-coverage discrete hole wall cooling

The heat/mass transfer for flow is studied through perforated plates for application to combustor wall and turbine blade film cooling. The results indicate that heat/mass transfer coefficients inside the hole surface vary significantly due to flow separation and reattachment. The transfer coefficient near the reattachment point is about four and half times that for a fully developed circular tube flow. The heat/mass transfer coefficient on the leeward surface has the same order as that on the windward surface because of a strong recirculation flow between neighboring jets from that array holes. For flow through in-line layers, the transfer coefficients affected by the gap spacing is approximately 100% higher on the windward surface of the second wall is about 20% lower on the side inside hole surface than that with a single layer.