Stator assembly for bounding the working medium flow path of a gas turbine engine

Claim 1

An arcuate duct segment for an axial flow gas turbine engine, the engine having a high pressure turbine, a low pressure turbine and a transition region extending between the turbines, the segment having an axis of radius R 1 , a convex side and a concave side disposed about the axis, the concave side adapting the duct segment to bound the transition region, which comprises: a first foot which extends circumferentially about the convex side of the segment, which is radially oriented with respect to the axis R 1 , and which has a radial length R f1 from the concave side; a second foot which extends circumferentially about the convex side of the segment, which is radially oriented with respect to the axis R 1 , which has a radial length R f2 from the concave side and which is spaced axially from the first foot by a first distance D 1 ; a transition piece having said concave side which is angled with respect to the axis of the segment, which has a span extending between the first foot and the second foot for joining the first foot to the second foot and which has an extension projecting from the first foot in cantilevered fashion and extending a second distance D 2 from the first foot; wherein the distance D 2 is equal to or greater than the first distance D 1 and wherein the radial length R f1 of the first foot is greater than one and one half times the radial length R f2 of the second foot such that a change in the length of the first foot facilitates accommodating a change in the angle of the concave side with respect to the axis of the segment during a redesign of the turbine which causes the diameter of the flow path of the high pressure turbine to change with respect to the flow path of the low pressure turbine.