The Effects Of Thermal Gradients On The Performance of Axial Compressors

The effects of thermal gradients and hot streaks on the durability and performance of high-pressure turbine airfoils have received considerable attention during the last decade. Compressor flow fields can also experience large temperature gradients when the machine is throttled from a high-rotation speed to a significantly lower rotation speed. In the current investigation, an unsteady, quasi-three-dimensional Navier-Stokes analysis has been used to investigate the physics of thermal gradients in a compressor rotor, typical of rotors used in the high-pressure compressors of commercial jet engines. Simulations have been performed for a wide range of operating conditions, and for different thermal gradients. The predicted results indicate that the thermal gradients can increase the losses in compressors.