Characteristics of Turbulent Forced Convective Nanofluid Flow and Heat Transfer in a 2D Axisymmetric Corrugated Pipe

A computational investigation using a single-phase model has been carried out for a turbulent forced convective nanofluid flow composed of water and Al2O3 nanoparticles through a horizontal corrugated pipe. A uniform heat flux boundary condition is imposed on the corrugated pipe wall. The Reynolds-Averaged Navier-Stokes and energy equations, along with Shear Stress Transport turbulence model, are solved utilizing the finite element technique. Parametric simulations are conducted by varying corrugation heights (0 <= h <= 0.07952D, where D is the mean diameter of the pipe), K ' arm ' an number (Re tau = 180, 250, 314), corrugation frequency (fc = 12, 15, 18), the volume percentage of nanoparticles (0 <= phi <= 0.02). Normalized mean velocity, mean temperature, radial heat flux, and Reynolds shear stress profiles are plotted to show the effects of governing parameters. Besides, the resemblance in average Nusselt number and friction factor are presented. To grasp the effectiveness of heat transfer, thermal efficiency has been calculated to find the optimum condition, and it reveals that the critical corrugation height, h = 0.0318D at Re tau = 314, fc = 18, phi = 2% corresponds to higher thermal efficiency.