LES of unsteady boundary-layer development from a pulsed impinging jet

Abstract

The boundary layer (BL) development under non-equilibrium conditions arising from a pulsed impinging jet impacting a wall at an angle is part of the complex flow physics occurring within an internal combustion engine. Capturing this development is crucial for predicting the correct heat transfer across the walls. Modelling the near-wall behaviour currently utilises wall functions derived from the log-law of the wall established for the equilibrium BL. However, given the unsteady nature of the problem, it is not fully understood whether the current wall functions can model the correct behaviour. Thus, in this paper, we try to evaluate whether the log-law of the wall is valid for the BL develo..