Abstract: Based on the flow and heat transfer in the channel of a new type of pierced rectangular vortex generator (PRVG), the fluid-solid coupled convective heat transfer process with flexible body inserted in the channel was simulated to study the influence of the oscillation of PRVG on the vorticity field and heat transfer performance in the channel, and to explore the mechanism of heat transfer enhancement by the fluid-solid coupling. Results show that the flexible body would produce trailing vortex in the flow field during the deformation process, and when the body reaches its maximum bending degree in a beating cycle, the trailing vortex would fall off into the wake flow at the trailing edge, making the cold and hot fluid mix violently, thus enhancing the heat transfer. With the increase of Re, the heat transfer intensity tends to increase. When Re=3 000, installing a single flexible body in the channel could increase the intensity of the convective heat transfer by 39.4%.