Response Surface Optimization And Forming Analysis Of Aluminum Alloy Topology Wing Rib Honeycomb Sandwich Structure

Honeycomb sandwich structure has many advantages,such as high specific strength,high specific stiffness,light weight,sound absorption,heat insulation,vibration reduction,etc.,and has been widely used in missiles and aircraft.Existing studies show that the external and internal boundaries of the unmanned wing rib structure after topology optimization are mostly curves.It is impossible to evaluate the mass,strength and stiffness of the structure by traditional empirical formula or equivalent model when designing the honeycomb sandwich structure.As for the composite honeycomb core,when it is used in the structure with complex boundary,the boundary layer fracture of core will result in the decrease of mechanical properties during machining.Therefore,this paper mainly focuses on the above two aspects,and the specific research contents are as follows:Modeling and force analysis of UAV wing were carried out,and the methods of numerical simulation of wing load distribution and evaluation of adhesive mechanical properties were analyzed.The deformation and stress distribution of standard honeycomb structure subjected to vertical panel loading were analyzed.At the same time,a modeling method of boundary reconstruction is proposed to improve the mechanical properties of the wing-rib honeycomb sandwich structure studied in this paper.The deformation and stress distribution of the structure are compared with the standard honeycomb structure.After the load distribution of the wing was obtained by the flow field simulation analysis,the overall topology optimization was carried out for all the wing ribs under the guidance of maximum element pressure to obtain the initial model for honeycomb sandwich structure design,and the mechanical properties of the structure were compared with that of the traditional open and reduced hole rib structure.The BBD response surface optimization test was carried out with the side length,wall thickness and height of the honeycomb cell as the design variables,and the overall deformation,equivalent stress and mass of the structure as the response objectives.The influence degree of design variables and their interaction on the response target was obtained by analyzing 17 groups of sample data.The multivariate functional relationship between the response target and the design variables is obtained by fitting.Based on several fitting functions and constrained by the finite element analysis results of the topological wing rib structure,a mathematical model for structural optimization of the honeycomb sandwich structure of the topological wing rib was established,and the structural design problems were transformed into corresponding mathematical optimization problems.Through editing program,the feasible region under three dimensional space coordinates is analyzed.The mechanical properties of the honeycomb sandwich structure of the topological wing ribs formed by the integrated forming and adhesive bonding were analyzed respectively.In addition,the first six frequencies of the traditional cut-weight hole rib structure and the topological honeycomb sandwich structure are analyzed under the constraint mode,and the corresponding deformation rules are obtained.