摘要

The thermal entry region in laminar flow of Bingham plastics within concentric annular ducts is solved analytically through the classical integral transform technique. Boundary conditions of the first kind are prescribed either at the inner or outer wall duct in order to verity the effects on the temperature field in the fluid. Nusselt numbers axe calculated along both the thermal entry and fully developed regions with high accuracy for different yield numbers and aspect ratios, which are systematically tabulated and graphically presented.