Based on momentum source method of calculating the ducted fan aerodynamic performance

the response surface method and neural network method were applied to aerodynamic optimization design of the NASA duct

and the optimization results were verified by CFD method.The optimization design results show that the two methods have achieved good effect.In the state of hovering

compared with the original duct

duct lift increased by 19.4% based on the response surface method

and duct lift increased by 21.2% based on the neural network method.In addition

in order to study the mechanism of duct lift more carefully

the duct was modeled

and partitioning method was adopted to divide the duct into 6 zones to obtain the duct lift distribution in the 6 regions.This shows that negative pressure formed on duct lip is a main factor to produce additional duct lift

and the duct lip near the interior duct provides higher lift.This optimization method can be effectively applied to the ducted fan aerodynamic optimization design.