Impact of deterministic correlations on the steady flow field

Abstract

A time-dependent numerical simulation of a single-stage transonic turbine is used as a direct simulation of stator-rotor interactions. The different parts of the deterministic correlations are computed and compared. The present work aims to provide insight into the influence of these correlations on the steady flow field of the average-passage equation system. This is related to the deterministic models of the literature. Several steady computations are performed with the various correlations. These results are compared with the time-averaged flow field. The impact of boundary conditions is also studied to highlight the importance of the non-uniform circumferential distribution at the so-called ‘mixing plane’. This work establishes that a non-uniform circumferential distribution is a key to ensure the success of steady computation. Furthermore, it demonstrates that full deterministic correlations are necessary to reproduce the time-averaged flow field. Spatial correlations are thus insufficient to model the stator wakes that interact with the rotor. Steady computations using only spatial correlations give less accurate results than those obtained without any correlation. This is a serious flaw of most of the literature's models.