Turbomachine rotor blade with an airfoil having a variable elliptical trailing edge

A turbomachine, comprising;

• a compressor;
• a combustor disposed downstream from the compressor;
• and
• a turbine disposed downstream from the combustor, the turbine including a rotor shaft extending along an axial direction through the turbine and a rotor blade connected to the rotor shaft, an airfoil of the rotor blade comprising:
• a root;
• a tip spaced radially outward from the root, the root and the tip defining a span of the airfoil therebetween;
• a leading edge extending across the span of the airfoil from the root to the tip;
• a trailing edge downstream of the leading edge along a flow direction, the trailing edge extending across the span of the airfoil from the root to the tip;
• a pressure side surface extending between the root and the tip and extending between the leading edge and the trailing edge;
• a suction side surface extending between the root and the tip and extending between the leading edge and the trailing edge, the suction side surface opposing the pressure side surface, the pressure side surface and the suction side surface continuous about the trailing edge;
• and
• an arc centered on the trailing edge and collectively defined by a portion of the pressure side surface and a portion of the suction side surface, the arc having a semi-major axis and a semi-minor axis;
• wherein the semi-major axis and the semi-minor axis of the arc define an axis ratio and the axis ratio varies over the span of the airfoil, wherein the arc is generally circularly shaped at the root and the tip of the airfoil, and wherein the arc is elliptically shaped between the root and the tip of the airfoil.