Detection of the persistency of the blockages symmetry influence on the multi-scale cross-correlations of the velocity fields in internal turbulent flows in pipelines

Abstract

In this paper we analyze the influence of obstacles symmetry on the development of the turbulent flow of a fluid through a pipeline. The analysis is based on the numerical solutions of the Navier–Stokes equations for the velocity field. The influence of the obstacle symmetry on the turbulence is detected by changing their shape while keeping the blockage ratio constant and calculating velocity field cross-correlations on the time series resulting from the simulation. The Detrended Cross-Correlation coefficient (ρDCCA) is applied to obtain two-point correlations located at different regions of the channel: at mid-channel and near the walls (above and below). With this cross-correlation coefficient we quantify how far from the obstructions these coefficients become independent on the obstructions shape, establishing a scale for the obstruction symmetry memory loss.