Fluid flow and heat transfer in internally finned helical coils

The equations of motion and energy for Newtonian fully developed fluid flow in an internally finned helical coil were solved numerically for the case of uniform heat flux with peripherally uniform temperature for low Reynolds numbers. Plots for the axial velocity, secondary stream function and fluid temperature are given. For a given fin geometry, it was found that fRe is both a function of Dean number and radius of curvature, whereas the average Nusselt number is a function of Dean number only. For a given fluid at a constant pressure drop, a finned coil gave lower values for the average Nusselt number than a finless tube with the same inside diameter and radius of curvature.