Principal component analysis on a LES of a squared ribbed channel

Abstract

The present paper reports on the application of Principal Component Analysis (PCA) on the flow and thermal fields generated by the large-eddy simulation (LES) of a square ribbed duct heated by a constant heat flux applied over the bottom surface of the duct. PCA allows to understand the complexity of the resulting turbulent heat transfer process, identifying the flow and thermal quantities which are most relevant to the process. Different algorithms have been employed to perform this analysis, showing high correlation between turbulent coherent structures, identified by Q−criterion, and the heat transfer quantified by the non-dimensional magnitude Enhancement Factor (EF), both identified as Principal Variables (PV) of the process.