## 1 Introduction  
Distributed electric propulsion (DEP) technology fully utilizes the size-independent characteristics of a motor system to transform the centralized power layout of conventional aircraft into a distributed propulsion layout according to design requirements. It can achieve an optimal integration of aerodynamics, structure, and power, bringing unprecedented impact to green aviation [1]. With the help of large-scale slip/jet disturbances brought by distributed power, it is expected to greatly improve the aerodynamic performance of aircraft, that is, the suction effect of distributed power can effectively increase the air velocity near the fuselage and, to some extent, suppress the flow of airflow along a spanwise direction [2], resulting in a significant increase in the lift coefficient and lift-to-drag ratio of the aircraft. Many researchers have utilized the efficient lift enhancement effect of distributed electric propulsion systems to develop various types of VSTOL vehicle platform [3, 4, 5]. Distributed-power fixed-wing unmanned aerial vehicles have great advantages in terms of their aerodynamic characteristics, takeoff and landing characteristics, environmental friendliness, and flight control robustness. However, due to the coupling between multiple power sources and wing surfaces, research on the flight dynamics and control of this type of unmanned aerial vehicle also faces a series of complex challenges, such as aerodynamic models considering the influence of distributed-power slipstreams as well as vertical/short takeoff and landing control strategies within the large envelope range. There are currently two main research methods for modeling the coupled dynamics of power/wing surfaces: theoretical model derivation and engineering test estimation. [PERSON] [6] used the lift line method to simulate interactions between propellers and wings, considering the influence of slip boundaries on lift distribution. However, the accuracy of this method is related to computational complexity, and a large amount of computation is required to obtain accurate results. [PERSON] et al. [7] established a propeller slipstream model considering the acceleration and slipstream diffusion in a propeller slipstream region using simple analytical derivation and semi-empirical equations and designed measurement experiments to determine the semi-empirical coefficients of the established model. [PERSON] [8] used the wing segmentation method combined with the assumption of a flat plate to segment a wing according to different inflow conditions. Based on the propeller inflow velocity and control surface deflection angle, the aerodynamic coefficients of each section of the wing were calculated in real time to form a fully maneuverable mechanical model of the influence of propeller slip flow. [PERSON] et al. developed a MAVion vertical takeoff and landing unmanned aerial vehicle [9], which combines flow velocity and Slipstream induced velocity as the equivalent airspeed of the drone and introduces a dynamic aerodynamic interaction factor to describe the interaction between the propeller slip and wing surface. [PERSON] [10] developed a fast calculation method for culvert jet velocity by combining the culvert flow field model and the culvert thrust enhancement coefficient and completed the derivation of a propulsion aerodynamic coupling model based on momentum theory for the presence/absence of dynamic input states. [PERSON] [11] used a balance force measurement system to obtain the tension coefficient, height, spacing, and the effect of propeller forward and reverse rotation on the aerodynamic characteristics of a distributed-power layout wing propeller. [PERSON] [12] established a coaxial twin-rotor ducted aerodynamic model and a thrust ducted aerodynamic model based on characteristic cross-section calculation using the theory of blade element momentum combined with experimental data and identified the model parameters through experiments.