Cooling of a turbine vane endwall through contouring and flow injection

High oil prices and environmental concerns serve to drive up the efficiencies of land based, power generation gas turbines. Increasing efficiencies requires raising the temperature of the air entering the turbine section of the engine. Turbine components must be protected from the increased air temperatures by advanced cooling designs that provide coolant to the hot flow surfaces. Secondary flows reduce the effectiveness of coolant injected along the vane endwalls as well as increase endwall heat transfer. Endwall contouring and strategic coolant injection can alter secondary flows to allow for improved endwall cooling, ultimately allowing for higher engine efficiencies.;This research initially focused on understanding the flow physics and subsequent cooling characteristics of an axisymmetric contoured vane passage. Results indicated that coolant injected from discrete holes provided lower effectiveness values on the contoured endwall in comparison to the flat endwalls of the planar and contoured passages. Coolant coverage from the upstream interface slot, however, was spread over a larger area of the contoured endwall in comparison to the flat endwalls as the interface slot was oriented closer to the plane of the contoured endwall. Seeking a fundamental understanding of interface slot coolant injection, further investigation into the effects of orientation and position of slot injection on secondary flows and the net heat flux experienced by a vane endwall was conducted. Results indicated that cooling effectiveness levels can be improved and the horseshoe vortex reduced in size by moving the interface slot closer to the passage inlet. At large injection rates, reducing the slot orientation resulted in the removal of the horseshoe vortex and a subsequent reduction in passage secondary flows leading to a reduction in the average heat load experienced by the endwall.