Efficient design method for blades of counter-rotating ducted fan

The design method for the blades of a counter‑rotating ducted fan based on blade element momentum theory has a fast design speed， but the design accuracy is not high. In order to improve the design accuracy and maintain the design speed， the fast design method based on blade element momentum theory was modified by CFD to propose an efficient design method for the blades of the counter‑rotating ducted fan coupled with CFD modification. Through continuous iteration of the CFD calculation and modified design， the design results were converged to the CFD results， and the blades meeting the design requirements were obtained. The results showed that the MRF method was not accurate enough to solve the performance of the counter ‑ rotating ducted fan，and the unsteady CFD method should be used. After modifying the blade thrust ratio，the inflow angle and blade aerodynamic forces through the CFD results， the design accuracy of the total thrust was improved by 10. 4%， and the design accuracy of the torque was improved by 18. 2%. The efficient design method used can better meet the design requirements with a small amount of CFD modifications. In addition， the design efficiency was further improved by 25% through the accelerated processing. © 2022 BUAA Press. All rights reserved.