Design Research On Aerodynamic Shape Of Long-endurance Unmanned Helicopter

Aerodynamic shape of long-endurance unmanned helicopter has very important influence onits flight resistance, and the fuselage resistance is the primary source of flight resistance.In thispaper,we combine with the fuselage arrangement in the overall design requirements,mainly studyaerodynamic shape of long-endurance unmanned helicopter fuselage.In order to study the aerodynamic characteristics of different configurational fuselage,calculate and analyze its aerodynamic characteristics respectively, get the flow field distributionaround the fuselage,coefficient of surface pressure distribution and the fuselage aerodynamiccalculation results of different configurational fuselage. By comparing of the pressure coefficientdistribution along the line at the top and bottom, summing up the surface pressure coefficientdistribution rule of smaller drag coefficient fuselage.The fuselage is divided into three sections, respectively the fuselage head, middle and tailbeam of fuselage. In order to facilitate the fuselage shape optimization design,this articlerespectively build the fuselage head shape, symmetry, and the length of the tail beam by the CSTparameterization, and analyze and calculate aerodynamic characteristics of different shapefuselage by the CFD. On the basis of calculation results, analyze the influence of different shapeparameters on the fuselage aerodynamic characteristics.Using Latin super vertical method, selecting experimental design sample points;Calculatingthe drag coefficient of sample points, building the Kriging agent model; In isight optimizationframework, selects the sequential quadratic programming to optimize and design the fuselageaerodynamic shape. On this basis, combined with hub fairing, landing gear and vertical tail,analyze the aerodynamic characteristics.Using design fuselage model to do wind tunnel test,measuring aerodynamic force and moment of the fuselage model under different wind speed anddifferent angle of attack and yaw angle. Compare calculation value and experimental value,analyzing the size of the CFD calculation error.