Vortex identification and evolution of a jet in cross flow based on Rortex

Jet in cross flow is an important issue in engineering practice, for example, it is used to improve turbine efficiency in film cooling. In this study, the large eddy simulation and the spectrum analysis are employed to analyze the vortices in a jet in cross flow. The results show that the Rortex method more accurately identifies the vortex structures than other methods. In the analysis of the evolution of the spatial vortex structures, it is affirmed that the spectrum analysis using the Rortex value can effectively identify the characteristic vortex structures in a jet in cross flow.