Aerodynamic Optimization Of Supercritical Airfoil And Aerodynamic Analysis Of Supercritical Wing

Airfoil design is the basis of wing design and an outstanding airfoil will improve the aerodynamic efficiency,safety,comfort and environment protection of an airplane.The CST parameterization method,the control parameters of which have specific geometry meaning,was used to represent the airfoil.The initial airfoil NSC(2)-0714 was undercut by adjusting the control parameters in order to generate an airfoil with pressure distribution approaching the design requirement.The pressure distribution of the supercritical airfoil was constrained in the process of optimization,at the same time,the design principle of supercritical airfoil was integrated in the constraint and objective function,which will guide the optimization and guarantee the supercritical airfoil characteristic.The airfoil after undercut was added in the initial population and two sets of optimization were conducted using muti-objective genetic algorithm NSGA?: The first set conducting one-point optimization without considering sonic-plateau pressure distribution;the second set conducting two point optimization considering sonic-plateau pressure distribution.The research results show that: The design point will achieve fine drag characteristic with 6.4% drag coefficient decrease in one point optimization,but this will sacrifice the drag characteristic of the design point nearby,which means a fairly big drag creep;the design point will achieve 5.2% drag coefficient decrease in two point optimization and the design point nearby still have good drag characteristic,which means fairly small drag creep.Drag prediction of wing/body is the classical task of airplane aerodynamic analysis and designing of a well-bahavier aerodynamic airplane rely on an accurate drag prediction?The aerodynamic analysis of three modle-DLR-F4 wing/body,DLR-F6 wing/body and DLR-F6 wing/body/pylons/naccle were completed in this thesis.The precision achieved in the thesis was the same as most codes comparing with the experiment and other references.The distribution of pressure on the wing and naccle matched well with the experiment data.Three sets of mesh ware generated: corese/medium/fine,which were used for grid convergence study.The S-A and SST turbulence model were used and they both achieved grid convergence.There was 10 counts divation to the experiment using SST turbulent model.