Rapid Aerodynamic Shape Optimization Design Of Aircraft Based On Surrogate Model

The aerodynamic shape optimization design of aircraft plays a very important role in the overall design of the aircraft.It closely links with the trajectory and guidance control,aerodynamic heating design,structural design and stealth design and other subjects.It runs through the whole process of the aircraft design.In this paper,the blended-wing-body lifting body is used as the research object.According to the main characteristics of aerodynamic shape design,a rapid estimation system is designed,and the sensitivity analysis is carried out by orthogonal experiment design method.Then,the main design parameters are sampled with Latin Hypercube method.And,the samples will be fitting by the Kriging proxy model.Finally,the genetic algorithm optimization based on Kriging model,so as to realize the aerodynamic shape optimization design of fast.Firstly,in order to achieve fewer design variables accurately and conveniently describe the blended-wing-body lifting body,parameterized design for the blendedwing-body lifting body with Class/Shape transformation method,exponential function method and B-spline curve method.Secondly,based on the Patran's secondary development of the PCL language,the automatic generation of the surface unstructured grid is realized.The Matlab program is used to analysis the data of the grid file,and the input file is converted into the required input file.Based on the method of empirical formula of aerodynamic engineering based on panel method,the fast aerodynamic analysis of the blended-wing-body lifting body is realized.Finally,using ModelCenter integrated platform to build a system,which has the 3D geometry model,grid generation module,grid data conversion module and aerodynamic performance rapid calculation module.It can realise the fast generation of 3D model,the fast generation of mesh and the fast calculation of the aerodynamic characteristics.Then,the system is combined with the sampling method,the Kriging proxy model and genetic algorithm module provided by the Model Center to get the maximum lift-drag ratio and volumetric ratio.And the aerodynamic shape optimization design of the wing body is obtained by the Pareto front.Based on aircraft aerodynamic shape optimization design research,a fast,efficient and practical aerodynamic optimization system is designed and built,which realize the aerodynamic shape optimization design of the blended-wing-body lifting body aircraft based on Kriging model and global optimization of genetic algorithm.