junction flows that develop at the base of protruding obstructions occur in many applications. An unsteady horseshoe vortex is formed as a component of these junction flows, which increases the local heat transfer on the associated endwall. Augmenting this junction flow can be achieved through the injection of fluid upstream of the obstruction. This experimental study evaluated the effects of injection angle for a two-dimensional slot placed upstream of a vane leading-edge with four injection angles of 90 degrees, 65 degrees, 45 degrees, and 30 degrees. Results showed that high momentum injection increased the endwall heat transfer at each slot angle while low momentum injection resulted in a relatively lower augmentation of endwall heat transfer. A leading-edge vortex turning into the endwall was formed at the junction in the stagnation plane for high momentum injection at 90 and 65 while a leading-edge vortex turning away from the wall was formed for 45 degrees and 30 degrees injection. For low momentum injection, a vortex turning into the endwall was formed at all injection angles. (C) 2012 Elsevier Ltd. All rights reserved.