The intensity of the vortex structure in a two-layer impinging stream reactor was quantitatively analyzed according to the Liutex method. The bound vortex, trapped vortex, and longitudinal vortex in the reactor were studied for the first time. The formation of vortices is related to the velocity field and pressure field. In this paper, the field synergy theory is used to evaluate their synergy.

Abstract

The structure of the turbulent vortex in a two-layer impinging stream reactor was studied by large eddy simulation. The distributions of vortex intensity, turbulent kinetic energy, and shear stress at different Reynolds numbers Re, nozzle spacings L, and nozzle layer spacings are discussed. The relationship between vortex structure and mixing effect in the flow field is revealed. The effects of longitudinal swirls and shear flow characteristics are analyzed. Finally, the field synergy theory is used for evaluation. With increasing Re, the vortex intensity and average shear stress increase. The nozzle spacing and layer spacing affect the mixing effect in the reactor by controlling the change of vortex structure in the flow field. When L/D = 3, where D is the nozzle diameter, the energy loss is the smallest and the mixing effect is the best. The research results provide a theoretical reference for the structural optimization of the impinging stream reactor.