Proper orthogonal decomposition analysis of the large-scale dynamics of a round turbulent jet in counterflow

The understanding of the large-scale dynamics of the turbulent jet in counterflow remains limited. By employing proper orthogonal decomposition and spectral proper orthogonal decomposition on large eddy simulation data, new insights are presented. The fundamental mode dynamics are described as varying penetration, precession, and an alternating stretching-contracting motion. Furthermore, intermittency in the temporal evolution of these modes is identified.