Optimized Design of Ejector Secondary Flow based on Response Surface Method

This paper uses the ejection ratio as the performance evaluation index and takes its maximization as the optimization objective. The radius, height, and position of the secondary-flow inlet are selected as optimization variables. A response surface optimization method is applied to analyze 15 sets of sample data and determine the optimal combination of the three parameters. First, a geometric model is established using DM, and the mesh is generated in Fluent-Meshing. Numerical simulations are then conducted in Fluent to obtain the ejection ratio under different working conditions. To improve the ejector performance, parameter optimization is carried out using the response surface method. The optimal design parameters obtained are: inlet radius of 3 mm, inlet height of 5 mm, and inlet position distance of 27 mm. The ejection ratio is increased to approximately 4.6, representing an improvement of about 14.7% compared with the original design. Finally, verification results show a small error, confirming the reliability of the optimized results.