Fast calculation and optimization of ducted propeller based on slipstream tube model

The computational method of ducted propeller based on CFD requires much more resources and long time when it involves works such as iterative calculation and optimization. In order to effectively reduce the computational cost of these kinds of work in preliminary optimization, a fast calculation method for ducted propeller was developed by coupling the surface panel method with the slipstream tube wake model, and fast optimization design for the duct wall shape of a ducted fan based on this method was carried out. The results showed that the method effectively reduced the computing resource requirement, while retaining high accuracy. The method can also be applied to fast calculation of ducted fans with non-circular inlet and outlet. The flow field analysis based on CFD showed that the expansion angle of the duct wall was reduced, the adverse pressure gradient of the duct wall was curtailed, the existing flow separation was eliminated, and the inlet velocity of the impeller was lowered down, thereby improving its efficiency and increasing the overall propulsive efficiency of the ducted fan by 20.7%. It demonstrated the effectiveness of the preliminary rapid optimization method of the ducted fan in finding the optimal direction. © 2024 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.