Abstract: In this paper, the incidence ratio is taken as the evaluation index of work performance, the incidence ratio is the optimization target, the secondary inflow radius, height and position are the variables, and the response surface optimization method is used to analyze 15 sets of sample data, and obtain the optimal value of the three parameters.First, a geometric model is established using DM and meshed in Fluent-meshing. Then, the model simulation is conducted in Fluent to obtain the ejection ratio. To improve the ejection ratio, response surface optimization is employed, ultimately yielding optimal data: an inlet radius of 3 mm, height of 5 mm, and position distance of 27 mm. The ejection ratio increased to approximately 4.6, representing a 14% improvement compared to the original value. Finally, verification calculations show that the error is minimal.