CALCULATION OF HEAT-TRANSFER IN A RADIALLY ROTATING COOLANT PASSAGE

The three-dimensional flow field and heat transfer in a radially rotat ing coolant passage are studied numerically. The passage chosen has a square cross section with smooth isothermal walls of finite length. Th e axis of rotation is normal to the flow direction with the flow radia lly outward. The effects of Coriolis forces, centrifugal buoyancy, and fluid Reynolds number on the flow and heat transfer have all been con sidered. The analysis has been performed by using a fully elliptic, th ree-dimensional body-fitted computational fluid dynamics code based on pressure correction techniques. The numerical technique employs a mul tigrid iterative solution procedure and the standard k - epsilon turbu lence model for both the hydrodynamics and heat transfer. The effect o f rotation is included by considering the governing equations of motio n in a relative frame of reference that moves with the passage. The co nsequence of rotation is to bring higher velocity fluid from the core to the trailing surface, thereby increasing Both the friction and heat transfer at this face. At tire same time, the heat transfer is predic ted to decrease along the leading surface. The effect of buoyancy is t o increase the radial velocity of the fluid, thus generally increasing the heat transfer along both the leading and trailing surfaces. These effects and trends that have been predicted are in agreement with exp erimental heat transfer data available in the literature [1,2]. The qu antitative agreement with the data was also found to be quite satisfac tory.