Study Of Aerodynamic Characteristics Of Aerocraft With Local Profile Deformation

In recent years, the rapidly development of several subjects such as bionics, intelligent materials and modern control study spurs the aerospace industry booming vigorously. Intelligent deformation aircraft are widely spread and highly concerned as a new born concept and research field. Intelligent deformation aircraft is widely recognized to be a crossover compound application of aerodynamics, flight mechanics, intelligent materials science, modern control engineering and mechanical engineering. The flight performance of aircraft is improved by changing the physical appearance of aircraft in order to realize the high maneuverability of the adaptive optimization intelligent aircraft.This paper based on one innovative science fund– research of aerodynamic characteristics promotion of aerocraft with local profile deformation. Therefore, we focus on variability of pneumatic flowing mechanism and aircraft evolutionary regularity, intelligent deformation technology and realization mechanism of intelligent deformation aircraft. After that, the pneumatic analysis, wind tunnel test and design aspects of in-depth research are carried out.The main structure of this paper is shown as follows:First of all, by investigating the development history of intelligent deformation aircraft domestic and overseas in recent years, we learn the overall principles and rules of intelligent deformation aircraft design.Secondly, we study the aerodynamic characteristics of aerocraft with various local profile deformation projects in different flow velocity using general computational fluid dynamics software– FLUENT. By analysis the pneumatic lift, drag and yawing moment coefficient, qualitative changing conclusion are made that the greater the head-deformation is and the closer the deformation gets to the head of aerocraft, the greater the aerocraft's yawing characteristics are improved. At the same time, the influence of the overall yawing characteristics with local profile distortion is getting bigger with the increase of flow velocity.Thirdly, low speed wind tunnel experiments are carried out to examine the flight condition of aircraft model. The aerodynamic characteristics of aircraft under diverse head bulge and cross-section deformation projects are analyzed and testified. Therefore, quantitative conclusions about aerodynamic characteristics of aircraft with local profile deformation are made according to a lot of numerical simulation and experimental results.Last but not the least, we analysis and compare the advantages and disadvantages of several intelligent materials such as piezoelectric materials, magnetostrictive materials and shape memory alloy materials and so on. Then shape memory alloy are chose to be the most suitable material for deformation in pretty small space at the head of aircraft. On this basis, several deformation mechanisms are designed driving by shape memory alloy including single bulge deformation, multi– bulge section deformation and torsional deformation mechanism.