Modeling of Fluid Flow Cooling of High-Speed Rotational Electrical Devices

Abstract

Internal cooling conditions in rotational electrical machines differs strongly from fluid contact with rotor surfaces, angular velocities, fluid flow thermal and mass characteristics, etc. Fast transients, decreasing internal gaps, different surface properties make cooling conditions difficult for accurate estimation. Here is presented a computational fluid dynamics model of fluid cooling over a rotating surface. Model estimates partial fluid flow velocities, and temperature distributions inside a simplified rotating device. Special attention is focused on the contacting fluid layer, directly interacting with rotational surface. Transient results about heat exchange ability according to rotational speed are acquired and discussed.