A numerical investigation of entropy generation in the entrance region of curved pipes at constant wall temperature

In this study, developing incompressible viscous flow and heat transfer in the curved pipes are studied numerically to analyze the entropy generation and thermodynamic optimization in the entrance region at a constant wall temperature. The governing equations including continuity, momentum and energy equations are solved using a second order finite difference method based on the projection algorithm. Entropy generation and optimal Reynolds number calculation based on the entropy generation minimization are carried out for two cases considering the two groups of non-dimensional parameters both numerically and analytically. The comparison of the numerical results in the entrance region with the analytical ones in the fully developed region indicates that both solutions predict nearly the same optimal Reynolds numbers, specially, for the first group of the non-dimensional parameters. ► Numerical study of a three dimensional developing incompressible viscous flow in curved pipes with a constant wall temperature. ► Entropy generation and optimal Reynolds number calculation based on the entropy generation minimization. ► Entrance region are compared with the analytical prediction in the fully developed region. ► Prediction of nearly the same optimal Reynolds for developing and fully developed region in curved pipe flows.