Thermal gradient attenuation structure to mitigate rotor bow in turbine engine

A gas turbine engine defining an axial centerline and a longitudinal direction extended co-directional thereto and a radial direction extended from the axial centerline, the engine comprising:

• a rotor assembly comprising a shaft extended along the longitudinal direction, wherein a compressor rotor and a turbine rotor are each coupled to the shaft;
• a casing surrounding the rotor assembly, wherein the casing defines a first opening positioned directly outward of the turbine rotor in the radial direction, and a second opening positioned directly outward of the compressor rotor in the radial direction;
• a first manifold assembly coupled to the casing at the first opening;
• a second manifold assembly coupled to the casing at the second opening, wherein the first manifold assembly, the casing, and the second manifold assembly together define a thermal circuit in thermal communication with the rotor assembly;
• and
• a fluid flow device in fluid communication with the first manifold assembly,
• wherein the fluid flow device provides a flow of fluid to the first manifold assembly and through the thermal circuit, and
• further wherein the flow of fluid egresses from the thermal circuit at the second manifold assembly.