COOLED STATOR HEAT SHIELD

The present invention provides a stator heat shield for a gas turbine. The gas turbine includes a rotor defining an axis of rotation. The stator heat shield includes a plurality of cooling units disposed in array along the axis of rotation. Each of the cooling units includes an outside part facing hot gas path of the gas turbine, and an inside plate positioned on the outside part and exposed to cooling air, wherein the inside plate comprises a plurality of inlet openings formed through the inside plate to introduce the cooling air into the outside part and thereby impingement cooling of the hot gas washed wall of the outside part. The outside part includes a cooling air channel formed therein with a first central portion to receive the cooling air, and a second spiral portion around the first central portion to convey the cooling air outward to a cooling air outlet of the second spiral portion. Initial investigation of the proposed cooling scheme in the present invention shows that the cooling air saving of 40% is expected compared to the common design.