A Numerical Study of Flow and Heat Transfer in Internally Finned Rotating Curved Pipes

Abstract

In this article, the effects of internal fins on an incompressible viscous flow and heat transfer inside rotating curved pipes are numerically studied under the hydrodynamically and thermally fully developed conditions. The fins are assumed to have negligible thickness with the same conditions as the pipe walls. Two thermal boundaries including constant wall temperature and constant heat flux are considered at the pipe wall. First the accuracy of the numerical code written by a finite-volume method based on the SIMPLE algorithm is verified by the available data for the finless rotating curved pipes. Then, the numerical results for the internally finned rotating pipes are investigated in both positive and negative rotation numbers affecting remarkably on the flow and temperature field patterns. Also, the Dean number (K_LC) effects on the friction factor, Nusselt number, and other nondimensional parameters are studied in detail. Analyzing the numerical results by the Colburn factor, two optimum fin heights consisting of the four-fifth of the pipe radius at the lower Dean numbers and one-third of the pipe radius at higher Dean numbers are determined in the curved rotating pipe with six internal fins.