Turbine vane airfoil with turning flow and axial/circumferential trailing edge configuration

A turbine vane comprising:

• a leading edge and a trailing edge, wherein the leading and trailing edges have an average span in a radial direction and wherein the radial direction is defined at a radially innermost point of the trailing edge;
• pressure and suction surfaces extending between the leading and trailing edges and defining an airfoil with turning flow therebetween;
• a midpoint chord extending in an axial direction between the leading edge and the trailing edge, wherein the midpoint chord defines a duct angle of at least fifteen degrees with respect to the axial direction and an aspect ratio of no greater than one with respect to the average span;
• and
• a radially inner region comprising a thirty percent span of the trailing edge, the radially inner region having an axial angle of no greater than four degrees and a circumferential angle of no greater than twenty degrees.

A turbine vane ring comprising:

• an inner flow annulus and an outer flow annulus coaxially oriented about a turbine axis;
• a plurality of vanes defining a turning flow direction about the turbine axis, each of the plurality of vanes comprising:
• leading and trailing edges extending for an average radial span between the inner flow annulus and the outer flow annulus;
• pressure and suction surfaces extending for an axial chord length between the leading and trailing edges;
• an aspect ratio of no more than one, as defined by the average radial span and the axial chord length;
• a duct angle of at least fifteen degrees, as defined with respect to the turbine axis;
• an axial angle of no more than four degrees, as defined within a radially inner thirty percent span of the trailing edge;
• and
• a circumferential angle of no more than ten degrees, as defined within the radially inner thirty percent span and as measured into the turning flow direction.