-

Heat transfer in laminar flow in the thermal entry region of a semicircular duct with internally longitudinal fins has been studied. The fluid is the oil with Pr>5; therefore, it is assumed that the velocity profile is fully developed and the temperature profile is developing. As the physical properties of oil vary considerably with temperature, therefore, variations of physical properties with temperature have been considered. The
momentum and energy equations have been solved numerically for different geometries, obtained by varying the number and heights of the fins. The results
such obtained are compared with other research works and the agreement is bound to be very good.