Study on vortex shedding mechanism of square cylinder coupling with strong swirl flow

In order to stabilize combustion of highspeed gas, both the strong swirl and the flow around blunt bodies can form low velocity recirculation zone. The vortex shedding mechanism of the flow around bluff body with swirling flow through the central opening is predicted. Compared with the vortex shedding mechanism of the square cylinder blunt, the computational results show that the vortex shedding mechanism of the coupling combustion stabilizer is controlled by the vortex of the swirling flow instead of the cylindrical vortex. During one shedding period, the heat and mass can be enhanced by the vortex source which is brought by the vortex breaking. Also, the flow around bluff body with swirling flow through the central opening can reduce drag, increase the length of the recirculation zone and reflux mass, and increase the number of vortexes so as to enhance the heat and mass transfer. Thus, coupling combustion stabilizer can enhance the stability of flame.