Internal low pressure turbine case cooling

摘要

A low pressure turbine casing has a conical annular shell circumscribed about a centerline. A forward flange depends from a forward end of the annular shell and a forward hook extends aftwardly from the forward flange. First and second rails having first and second hooks, respectively, extend aftwardly from the annular shell. First and second cooling holes extend through the first and second rails, respectively. Cooling air feed holes extend through the forward flange. The first and second cooling holes may be radially disposed through the first and second rails, respectively, with respect to the centerline or disposed through the first and second rails at an oblique angle with respect to the centerline. A low pressure turbine casing and shroud assembly further includes a first annular cavity in fluid flow communication with the first cooling holes and the second cooling holes. A second annular cavity is in fluid flow communication with the first and second cooling holes.