Thermal interactions among the confining walls of a turbulent recirculating flow

Numerical solutions for the velocity and temperature fields in a cylindrical enclosure have been obtained to determine how the heat transfer at any one of the bounding walls is affected by the thermal boundary conditions at the other walls. The enclosure is a hollow cylinder closed at both ends by circular disks. A recirculating flow is induced within the enclosure by a fluid throughflow which enters via a central aperture in one of the disks and exits via an annular gap at the rim of the other disk. The analysis is based on the k-ε turbulence model, and the solutions were carried out by an elliptic finite difference procedure. Results were obtained for parametric values of the Reynolds number of the entering throughflow and of the length-to-radius ratio of the enclosure. The results show that the heat-transfer rates at the outlet disk and at the cylindrical wall are not greatly affected by the thermal boundary conditions at the other surfaces. On the other hand, the heat-transfer rate at the inlet disk is more sensitive to the thermal conditions at the other surfaces.