Analysis And Optimization For Energy-Absorbing Composite Structures With Uncertain Parameters

Due to the large deviation of material properties and inherent machining tolerance,uncertain factors should be considered for designing and analyzing composite structures. The fluctuations of these uncertain factors will change the energy absorption characteristics of the thin-walled composite tubes. The method to evaluation the energy absorption characteristics of the thin-walled composite tubes, and the method to design the thin-walled composite tubes was reasearched. The main reasearch content is as follows:1, Evaluation Method for the influence of parameters on the energy absorbing characteristics of the thin-walled composite tubesA Method was developed to evaluation the the influence of parameters on the energy absorbing characteristics of the thin-walled composite tubes: first, through the experiment of sample level to determine the distribution of the material performances of composite,and find the data to determine the distribution of feature sizes; Then, using the Plackett- Burman experimental design method and the finite element model evaluation the the influence of parameters on the energy absorbing characteristics of the thin-walled composite tubes.2, Evaluation method for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters base probabilityAn evaluation method based on probability for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters was proposed and developed herein. Response surface method was used to build a second-order function between uncertain parameters and the two indicators of energy-absorbing characteristics. At last used the monte carlo to get the probability of energy-absorbing characteristics..3, Evaluation method for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters base intervalAn evaluation method based on interval for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters was proposed and developed herein. Response surface method was then used to build a second-order function between uncertain parameters and the two indicators of energy-absorbing characteristics. Interval perturbation of the response surface function was at last performed to establish the interval ofthe energy-absorbing characteristics.4, Design method for thin-walled composite structures with uncertain parametersAn design method for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters was proposed and developed herein. first, center combination experimental design is used to determine the experimental matrix of design parameters; Then, evaluation method for energy-absorbing characteristics of thin-walled composite structures with uncertain parameters was used to get the mean and standard deviation of energy absorption characteristics; Response surface method was used to build a second-order function between design parameters and the mean and standard deviation of energy absorption characteristics; Finally, combining the response surface equation and the requirement of design optimization mathematical expression of the fmincon function in matlab optimization solution.