Numerical study of turbulent heat transfer and particle deposition in enhanced pipes with helical roughness

Abstract

Large-eddy simulations of turbulent heat transfer and solid particle deposition in helically rib-roughened pipe flows have been performed for different Reynolds numbers Re and various particle diameters Dp. An Euler–Lagrange approach, using cyclic boundary conditions for the continuous and the dispersed phase, have been applied to achieve a fully developed turbulent flow. An adhesion and removal model have been added to the multiphase large-eddy simulations to take into account the physical effect of particle re-entrainment. The complex interactions between particle-laden turbulent flow and the structured pipe wall in multiple-started helically ribbed pipes are numerically investigated with regard to heat transfer, pressure loss, and particulate deposition. The results of the Nusselt numbers Nu, friction factors fd, and particle deposition rates Ṅd are presented for each geometry variant. For same Reynolds numbers Re, significant differences of those values have been observed for the differently structured pipes.