The Theory Of Research And Optimization Of Reanalysis Methods Based On Modal Analysis Of Laminates

In order to realize automobile lightweight,composite materials are widely used in automotive industry because of their good properties.The design and optimization of composite laminates require repeated iterative modifications.In the traditional design of laminates,every modification of laminates requires a complete simulation,which seriously affects the efficiency of the design.Reanalysis is a fast computational method based on the initial analysis results.It shows the advantages of computational efficiency in static,dynamic,nonlinear and other fields.However,there are few studies in modal reanalysis of composite laminates.Therefore,aiming at computational reduction of modal analysis for laminated plates,this study extends the reanalysis method to the modal analysis for composite materials,which can quickly calculate the eigenvalues and eigenvectors of laminated plates with modified geometry and ply angle.This study mainly includes the following aspects:(1)The combined approximation method with shifting is utilized to the modal analysis of laminated plates which is frequently calculated by the traditional finite element method.For the eigenvalue problems of laminates calculated by first-order shear deformation theory,the combined approximation method with shifting can avoid the time-consuming factorization.Thus,it can greatly reduce the computational cost,and also has a fairly high accuracy.It can well deal with the problems of laminate geometry and angle modification.(2)Reanalysis methods are extended to solve the modal problems of composite laminates based on isogeometric methods.Compared with the traditional finite element method,the isogeometric method is more accurate in describing the geometric model and realizes the integration of CAD and CAE.Therefore,more accurate analysis results can be obtained with it.The numerical examples show that the combined approximation method with shifting is effective in dealing with the modal reanalysis of laminates with global and local angle modification based on isogeometric analysis.(3)In order to take the advantage of computational efficiency of reanalysis for the real engineering problem,a reanalysis assisted metaheuristic optimization is proposed.In order to improve the efficiency of evaluation,a reanalysis assisted particle swarm optimization is proposed.The combined approximation method with shifting is added to the optimization algorithm as a fast solver.It is more efficient than the original particle swarm optimization.In addition,a matlab-Python-ABAQUS joint optimization program is developed to enable the proposed optimization algorithm to be applied in engineering.The numerical examples show that the proposed method can solve the modal optimization problem of laminates accurately and efficiently.