A film cooling apparatus with a cooling hole (46) in a component wall (40). A first surface (42) of the wall is subject to a hot gas flow (48). A second surface (44) receives a coolant gas (50). The coolant flows through the hole, then downstream over the first surface (42). One or more pairs of cooperating electrodes (60-61, 62-63, 80-81) generates and accelerates a plasma (70) that creates a body force acceleration (71, 82) in the coolant flow that urges the coolant flow to turn around the entry edge (57) and/or the exit edge (58) of the cooling hole without separating from the adjacent surface (47, 42). The electrodes may have a geometry that spreads the coolant into a fan shape over the hot surface (42) of the component wall (40).