A Study On Analyzing And Optimizing The Performance Of Outer Seals Of Car Window Belt-line

The outer seals of car window belt-line is an important part of the car sealing system and plays an important role in waterproofness,dustproof,noise insulation,vibration absorption and decoration.Assembly performance and compressive deformation characteristics are important indexes to evaluate the design effect of the outer seals of car window belt-line.By studying the calculation methods and structural optimization methods for the performance of the outer seals of car window belt-line,it can provide a useful reference for structural design and optimization of the seals,thereby improving the sealing performance of the vehicle.In this paper,an outer seals of car window belt-line is taken as the object of study.By comparing the analysis results of the three-dimensional finite element model and the two-dimensional finite element model,the analysis method of the assembly performance of the sealing strip on the outside of the window sill of the car is discussed,and a finite element model of the outer seals of car window belt-line assembly performance analysis is established.Based on the established finite element model,the assembly performance index of the seal was calculated,and the initial sample of the seal was tested according to the relevant test method.The measured value of the assembly performance index was compared with the calculated value of the finite element model.The results show that the simulation and calculation method is correct.There are many influencing factors on the assembly performance of the outer seals of car window belt-line.In this paper,the thickness of the strip,the height of the locating boss,the angle of the barb structure and the shape of the clamping tooth are selected as the design variables to analyze the influencing factors on the assembly performance of the outer seals of car window belt-line.According to the selected design variables,the design scheme was designed according to the orthogonal table,and the results of orthogonal experiments were analyzed by using the method of intuitive analysis.The results show that the shape of the clamping tooth has signicant influences on both the peak of insertion resistance and the clamping force.And it also indicates that by adjusting the shape of the clamping tooth can ensure the highest efficiency to meet the assembly performance requirements.By comparing the response surface model with BP neural network model,and multi-objective particle swarm optimization algorithm with multi-objective NSGA-II genetic algorithm,the optimization method of the assembly performance of the seals is presented by using the response surface model and multi-objective particle swarm optimization and the Pareto-set with a large number and fairly uniform distribution are obtained.Then,the maximum improvement selection method is presented to define the final solution from the Pareto-set,and the final solution is proved to be the most satisfactory solution.Therefore,the optimization method,which is presented by using the response surface model and multi-objective particle swarm optimization,is proved effective in optimizing the assembly performance of the outer seals of car window belt-line.The compressive deformation characteristics of the outer seals of car window belt-line were analyzed by using a method similar to estimating the assembly performance,and the analysis results are verified by experiments.According to the relation between the compression load and the frictional force of the lip of the seal,this paper proposes a new method to calculate the theoretical friction force by multiplying the compressive load and the sliding friction coefficient.The optimal compression of the seal lip and corresponding compression performance indicators are calculated.The same optimization method was used to optimize the compression performance of the outer seals of car window belt-line,and the optimization results were verified.The results show that the combination of response surface method and multi-objective particle swarm optimization algorithm to optimize the compression performance of the outer seals of car window belt-line is also effective.