Design And Analysis Of New Dual Ducted Four Rotor Unmanned Aerial Vehicle

With the vigorous development of China’s aviation industry,four rotorcraft aerial photography in the consumer market demand is increasingly strong.Four rotor UAV in the use of the air platform is usually required to carry high-precision equipment,so its stability requirements are very strict.But the four rotor UAV is limited by its own flight characteristics,the body is always in a state of instability,the need to maintain the stability of the equipment through the three-axis PTZ.But the actual flight will often exceed the scope of the application of PTZ.Therefore,the market is an urgent need for a flight when the body more stable air platform,and asked to retain the four rotor UAV vertical takeoff and landing,aerial hover and flexible mobile advantages.According to the above requirements,this paper puts forward a kind of unmanned aerial vehicle,which can realize vertical take-off and landing,hovering,yawing and fast cruising.On the basis of the conventional four rotor unmanned aerial vehicle,a set of ducted power system with propulsion and steering control is added.Rotor power is only responsible for providing vertical lift,and keep the body stable;dynamic speed control method for ducted power through the difference in the horizontal direction,so that the entire flight aircraft from takeoff to landing in the body will not have a tilt,and effectively reduce the resistance to enhance the speed of boats.The change of the propulsion mode of the utility model solves the disturbance of the existing four rotor aircraft to the airborne equipment due to the change of the attitude of the aircraft.On the basis of establishing the overall design requirements of the aircraft,this paper chooses the preliminary design scheme and elaborates its flight principle in detail.By calculating the overall parameters,combined with the design requirements to complete the overall design of the aircraft,and the main structural components of the initial structural design,the use of CATIA software to draw the whole three-dimensional model.On the basis of the above work,the prototype of the aircraft is completed.Since the vehicle power system is composed of rotor and channel,it is necessary to analyze the aerodynamic characteristics of the power system by CFD analysis in order to study the aerodynamic effect of the ductile power on the rotor.In this paper,the whole model of the machine is simplified as the calculation model of the rotor and the space position of the duct.After dividing the grid,it is imported into ANSYS Fluent software for numerical simulation.Taking the different installation position of the channel as a variable,the rotor lift data and the required figure are obtained.After analysis and study,the optimal installation position of the channel and the rotor is determined.Then,the optimal design of the ducted power system is made.By comparing the results of the ordinary duct and the convergence of the ducts in the same condition,the conclusion is drawn that the convergence duct will produce more tension.After the theoretical analysis,the prototype is tested by field test.The test results show that in the process of flight,the prototype body can always keep horizontal stability.The maximum speed of up to 19.2m/s,and the indicators are in line with the design requirements.Therefore,the feasibility and rationality of the scheme is verified,which lays a good foundation for the following research,especially for the research on the compound of rotor and ducted power.