Natural grid stretching for DNS of wall-bounded flows

Abstract

We propose a natural stretching function for DNS of wall-bounded flows, which blends uniform near-wall spacing with uniform resolution in terms of Kolmogorov units in the outer wall layer. Numerical simulations of pipe flow are used to educe optimal value of the blending parameter and of the wall grid spacing which guarantee accuracy and computational efficiency as a results of maximization of the allowed time step. Conclusions are supported by DNS carried out at sufficiently high Reynolds number that a near logarithmic layer is the mean velocity profile is present. Given a target Reynolds number, we provide a definite prescription for the number of grid points and grid clustering needed to achieve accurate results with optimal exploitation of resources.

References in corpus (3)

• Direct numerical simulation of turbulent channel flow up to $R{e}_{\tau }\approx 5200$
• Coherent structures in wall-bounded turbulence
• The unifying theory of scaling in thermal convection: The updated prefactors

Cited by in corpus (5)

• One-point statistics for turbulent pipe flow up to $R{e}_{\tau }\approx 6000$
• Assessment of heat transfer and Mach number effects on high-speed turbulent boundary layers
• On the streamwise velocity variance in the near-wall region of turbulent flows
• Turbulent mixed convection in vertical and horizontal channels
• Turbulent skin-friction drag reduction via spanwise forcing at high Reynolds number