Numerical Study on Flow and Heat Transfer Characteristics of Discrete Film Cooling Holes of the Sinusoidal Longitudinal Corrugated Heat Liner

Abstract

Abstract To understand film cooling flow fields and heat transfer characteristics of the longitudinal corrugated surface on afterburner heat liner, the numerical simulation was performed in approximate actual boundary conditions. The single hole and full film holes on the corrugated surface were investigated under different boundary conditions to study the heat transfer and discharge coefficient. The adverse pressure gradient on the leeward results in spanwise expansion of the airflow, while the favorable pressure gradient on the windward keeps the shape of the jet constant. The different hole spacing and hole row spacing in different positions of the corrugated surface should be considered due to the film covering characteristics. The film cooling holes at the same height on the leeward and windward share the similar laterally average effectiveness. The flow rate and discharge coefficient increase from crest to trough. Cross-flow has a negative influence on the discharge coefficient especially the inlet cross-flow. The cross-flow and discharge coefficient can be correlated with each other by a logarithmic function. The jet discharge coefficient on the windward surface is higher than that on the leeward surface, which is contrary to previous cognition. The reason is that the jet blocking causes the downstream pressure zone to advance, which counteracts and enhanced the siphon effect on the leeward and windward side respectively. As the inlet pressure of coolant increases, the film cooling effectiveness on the windward side is greatly improved in full film condition. However, it changes little on the leeward side.