Study On Lightweight Design And Mechanical Properties Of SPS Chimney Structure

SPS sandwich panels have excellent properties such as high strength,light weight,high specific stiffness,vibration reduction,noise reduction,etc.,and have received more and more attention in the field of ship structure design in recent years.In this paper,in order to realize the lightweight design of steel chimney structure,SPS sandwich panel is used to replace steel chimney to obtain SPS chimney structure design scheme;on the basis of mechanical performance analysis,the response surface method based on Box-Behnken test design is used to carry out the structure After optimizing the size,we get the optimization plan of the SPS chimney structure,and then analyze the vibration characteristics of the optimized structure of the SPS chimney,and study the changes of the structural vibration characteristics of the SPS chimney structure after the size optimization.The main research contents of this article are as follows:(1)Introduced the common methods of lightweight design and optimization of ship structure.By comparing the characteristics and application scope of methods such as topology optimization,shape optimization and size optimization,combined with the structural characteristics of SPS chimney structure,the experimental design is simple and the efficiency is high.,Which can better describe the design variables and the objective function of the response surface method to optimize the size of the structure,and introduces the selection of the design variables of the response surface optimization method,the determination of the constraints,the objective function and the optimization model test,etc.(2)Based on the principle of equal weight,the traditional steel stiffened chimney is used as an alternative structure,and four design schemes for the SPS chimney structure are proposed.According to the difficulty of manufacturing and processing of the structure,the weight of the structure itself is selected to meet the structure,please quantify the design requirements are used as the initial alternative design for the SPS chimney structure.Perform static strength analysis on the preliminary alternative design plan,and combine the static strength analysis results of the steel chimney replacement target and structural strength check criteria to analyze and verify the preliminary alternative plan.(3)Taking the lightweight design of the structure as the goal,the structural size optimization is selected as the way to achieve the lightweight structure,and the response surface method of the Box-Behnken test design is used to optimize the structural size of the SPS chimney structure: based on the structural displacement and equivalent stress In order to optimize the goal,the size and weight of the components are used as constraints,and an optimized mathematical model is established to obtain the optimized SPS chimney structure design with reduced weight.In order to apply the actual engineering requirements,the optimized structural size is adjusted to obtain two optimization schemes.(4)Comparing the weight-loss alternatives and the optimized design,the corresponding stress and displacement of the SPS chimney structure are obtained from the analysis results.The results show that the displacement of the optimized structural design scheme is reduced by 23.47% and 21.27%,the equivalent stress is reduced by 29.32% and 30.05%,and the weight is reduced by 10.04% and 10.83%,respectively.The strength and stiffness of the structure meet the requirements.Compared with the steel chimney replacement target,the optimized solution has a weight reduction of 12.39% and 13.16%,respectively.The structural size optimization meets the structural performance requirements while achieving the design goal of lightweighting the structure.(5)The vibration characteristics of the optimized structure of the SPS chimney were studied.The theoretical method was used to verify the accuracy and feasibility of the finite element simulation analysis of the vibration performance of the SPS sandwich panel.The alternative targets of the steel chimney,the weight reduction alternative SPS chimney structure,and the optimized SPS were compared.The analysis results of the natural frequency harmonious response of the chimney structure show that the vibration damping performance of the SPS chimney structure replaced by steel/polyurethane sandwich panel is better than that of the steel chimney structure.After the amplitude optimization in the response analysis increases slightly,the vibration damping performance of the overall structure of the SPS chimney is better than that of the steel chimney structure.