Growth of Turbulent Boundary Layer with Varying Inlet ‎Length Scales‎

Lee, Y. T.; Lim, H. C.

doi:10.47176/jafm.14.05.32628

Growth of Turbulent Boundary Layer with Varying Inlet ‎Length Scales‎

Authors

Y. T. Lee ¹
H. C. Lim ²

¹ School of Mechanical Engineering

² Pusan National University

10.47176/jafm.14.05.32628

Abstract

This study aims to generate a fully developed turbulent boundary layer in the channel domain using ‎LES (Large Eddy Simulation), suitable inflow conditions along with statistically reliable turbulent ‎characteristics are required. This study clarifies the effect of the integral length scale from the ‎existing data on the generation of turbulent boundary layers. In order to justify the work, an ‎artificially created boundary layer is imposed on the inlet section, which gradually evolves into a ‎fully developed turbulent boundary layer flow inside the numerical domain. In this study, the ‎synthetic inflow method, which is based on an exponential correlation function, is used by ‎imposing the spatial and temporal correlation between two different points on the inlet section. In ‎addition, we conducted parametric length scale studies on the inlet section and compare our results ‎with existing data. The results indicated that the cases of larger length scale in the span-wise ‎direction were not only effective in achieving the target shape of a fully developed turbulent ‎boundary layer, but also developed it faster than the smaller-length scales.‎

Keywords