Numerical of vortex characteristics in a counter flow contact-cyclone reactor for epoxidation of fatty acid methyl ester

Using Eulerian model and RSM model, the vortex characteristics of the flow field with a counter flow contact-cyclone reactor for epoxidation of fatty acid methyl esters were analyzed. The impinging stream technology was used to optimize the mixing and reaction of FAME and performic acid. By varying the impingement distance (L₁) and accelerator tube length (L₂), the vorticity, swirling strength, and vortex kinetic energy distribution of the flow field were discussed using vorticity, normalized swirling strength standard deviation, and Q-criterion. Furthermore, the vortex core interaction range and evolution process in the reactor were studied based on the radial variations of vorticity and swirling strength standard deviation. Significantly, when L₁ = 40 mm and L₂ = 30 mm, the development of the vorticity reached the optimal working condition. Analysis of vorticity and Q-criterion isosurfaces indicates that small-scale vortices are distributed near the impingement chamber walls, while large-scale vortices are located at the impingement center. Notably, the vortex structures in the counter flow contact chamber are dominated by horseshoe and ribbed vortices. The evolution of vortices in the radial plane of the counter flow contact chamber is divided into four stages according to Q-criterion variations, and the flow field stabilizes after t = 0.18 s.