Research On Aerodynamic Principle Of The Fan-wing Aircraft

The lift and thrust system of fan-wing consists of a fixed wing and a cross flow fan embedded into the topside of the fixed wing’s leading edge. Cross flow fan’s rotation makes the theoretical research on fan-wing’s aerodynamic principle much harder. This makes the theoreticla reasearch of fanwing aerodynamic principle harder. So, researchers at home and abroad conducted research on fan-wing manly from numerical simulation and wind tunnel test. However, in order to master the priciple of fan-wing aircraft, it is necessary for in-depth theoretical analysis of fan wing aerodynamic principle.Based on the existing fan wing research, this paper this paper divided fan-wing into four parts according to fan-wing’s structural features and characteristic of flow field. Each part’s contribution to aerodynamic principle is studied by slipstream theory, blade element theory, vortex theory and airfoil theory respectively.First, according to the exhausting characteristics of fan wing, fan wing’s slipstream model is established. Using the theory of momentum, aerodynamic force and power consuming of fan wing’s slipstream is studied. Second, using blade element theory, flow environment around fan wing’s blades and aerodynamic force as well as power consuming of fan are studied. Third, aerodynamic characteristics of eccentric vortex inside fanwing are analyzed through vortex theory. Besides, flow on the arc-groove of fanwing leading edge is simplified to the flow between two parallel panel. Considering the effect of eccentic vortex and fan rotation, aerodynamic force on arc-groove is studied. Fourth, according to characteristics of flow around fan wing, thick airfoil of fan wing is established by sewing up the opening in the leading edge of fan wing. Using the theory of airfoil, lift and push of thick airfoil are studied.At last, this paper analyzes the connection between the different methods and acquires both lift & thrust coefficient and required power of fan wing by summing up four parts’ achivement. What’s more, the results from theoretical research are contrasted with that from wind tunnel tests.