Integrated Design And Optimization Of The Aerodynamic Shape For Aircraft Under Hybrid-Wing-Body Configuration

A parametric modeling method was developed to describe the shape of aircrafts under the HybridWing-Body configuration.Based on the Blended-Wing-Body configuration,this parametric modeling method was proposed to optimize the aerodynamic performance of the HWB configuration.An integrated perspective was introduced in this method so that the central body,the outer wing and the tail can be considered at the same time.The NURBS technique was applied to generate CAD models for the HWB aircrafts automatically,and the models were stored in the IGES format natively.Programs for generating the multi-block structured grids for these models was wrote.The grids was smoothed based on the elliptic PDEs locally and was converted to unstructured format at last.The Navier-Stokes equations was solved numerically based on the generated grids,where the S-A turbulence model was applied,the flow term was discretized using the Roe scheme,the dissipation term was discretized with the JST scheme and the 4-step Runge-Kutta explicit time marching was adopt.Numeric Experiments indicate that the lift-drag performance was a little better than that in conventional configuration and the max L/D is about 22 at design point.At last,the Kriging surrogate model was applied to optimize the twist angles on the 3 profiles in spanwise direction.50 data points was sampled with the Latin Hypercube Sampling method,and the realcoded Genetic Algorithm was used to find the global optima.Numeric experiments indicate that,compared to the initial configuration,the optimized twist distribution contributes about 4% promotion in terms of the lift-drag performance.