Optimal Design of a Blast Basket in a Test Cell using a Differential Evolution Algorithm

One key component in a jet engine test cell is the blast basket, which mixes the jet flow exiting the nozzle with ambient air to aid in cooling, reducing velocity, and decreasing noise. The test cell uses the ejector pump method. Critical blast basket design parameters include diameter, length, and perforation pattern. In this study, the basket length is predefined, diameter is calculated from the augmentor design, and the hole count is based on material porosity. To evaluate mass flow uniformity, five ۲-meter-wide strips along the basket are modeled, aiming for uniform distribution across these strips. A major design challenge is flow concentration at the downstream end, so this study optimizes the hole configuration and cone angle at the basket’s end to improve distribution. The single-objective Differential Evolution method is employed, using hole diameter, material porosity, and outlet cone half-angle as design variables, with the objective function defined as minimizing the standard deviation of mass flow across the strips. The flow field was computed using ANSYS Fluent ۲۰۲۰ R۱ with the k–ω Shear Stress Transport  (SST) turbulence model, while geometry generation under design constraints is automated using a custom C code. Results show an ۱۸.۱% reduction in mass flow standard deviation compared to the baseline, indicating improved uniformity. Additionally, acoustic intensity at the strip exits decreases significantly, with reductions of ۵.۸۱%, ۱۵.۳۵%, ۳۱.۷۱%, and ۵۵.۱۳% across the first to fourth strips in the optimized configuration.

کلیدواژه ها:

Blast basket ، Differential evolution algorithm Optimum design ، Ambient air ، Differential Evolution (DE) method