Topology Optimization Of Key Structures Of Flexible Morphing Wing

As a principal structure which provides lift for an aircraft,wing directly influence the maneuver performance of the aircraft.In generally,the conventional fixed wing designed for a certain flight condition can not adapt to the requirement of aerodynamic performance for different flight tasks.A formidable challenge for aircraft designers is to design out a light-weight,high-stiff wing,and self-adaptive wings of changing aerodynamic performance with regard to flight conditions.The morphing wing is a way to improve the aerodynamic performance of an aircraft by changing its airfoil.Studies regarding morphing wing have drawn attention widely and built up rapidly.Currently,scholars abroad have designed out different kinds of morphing wings,some of which even have been tested successfully.This paper studies the topology optimization and design of flexible support structure of airfoil?support structure for flexible telescope skin and flexible rib of wing.The main works and contributions are as follows.(1)Starting with the analysis of optimization target of the flexible support structure of airfoil,the objective functions of multi-objective topology optimization are established.NSGA-II with connectivity analysis and morphological filter is employed for this problem,in which bit-matrix is used as the representation of a chromosome.The objectives such as mass,performances of deformation and load bearing ability of the feasible individuals are obtained by FEA(Finite Element Analysis)using ANSYS.NSGA-II is realized in MATLAB by penalizing the infeasible individuals.A series of optimal results of the support structure are obtained.It can be seen from the results that NSGA-II can provide feasible and effective solutions for multi-objective topology optimization of the flexible support structure of airfoil.(2)The objective functions of multi-objective topology optimization for the support structure of flexible telescope skin are established by analyzing the optimization target of the support structure.The design domain is discretized by hexagon.The mapping between design domain and the bit-matrix is established subsequently.Connectivity analysis and morphological filter are put forward.In order to improve the individuals in the frist front,a local optimization algorithm is proposed.Sequence of the feasible configurations of the support structure is obtained finally.It can be seen from the results that the method in this paper can provide feasible solutions for multi-objective topology optimization for the support structure of flexible telescope skin and solve other multi-objective topology optimization problems in 2D.(3)In order to build three-dimensional finite element model of rib of wing,the coordinates and pressure coefficients of nodes located on the profile are obtained using interpolation method.The optimization model for rib of wing is established using SIMP.OC with sensitivity filter is employed to solve this problem.Flexible ribs are attained via topology optimization for situations of maximum flexibility and given target deformation.