Performance Prediction And Structure Optimization Of Rubber Products

Rubber plays an irreplaceable role in rubber products such as rubber damper,tire and oil seal,because of its unique physical and chemical properties.In order to achieve the best performance of rubber products,it is necessary to design the product structure reasonably and to make full use of the material properties,so that it can be safely,economically and applicable to all kinds of products.The traditional structural design of rubber products depends on the design experience and a large number of test experiments,design cycle is long and cost is high,and it is difficult to obtain the optimal structure.By means of finite element simulation,the optimization technology is applied to the structural design of rubber products,which can greatly reduce the research and development cost and obtain the optimal structural parameters in accordance with the application conditions of products in a short research and development period.Optimization technology can be divided into topology optimization and parameter optimization according to optimization methods,which can be applied to a part at the same time or used in product design alone.According to the characteristics and application conditions of different rubber products,different optimization methods are used to optimize the treatment,so as to obtain the optimal structural parameters of rubber products.The main work includes three aspects as follows:First,when only the parameters range of rubber constitutive model and the specified size range of products are known,we integrate Abaqus and Data Matching modules into the Isight platform,and the parameters of constitutive model and several size of the rubber damper are optimized,The optimal structural parameters of rubber damper H=45.57 mm、L=40.57 mm、R=61.27°and the parameters of rubber Yeoh constitutive model C₁₀=0.542 MPa、C₂₀=0.022 MPa、C₃₀=1×10^-6 MPa,so that the load-displacement curve of rubber damper agrees with the target stiffness curve.With the help of the optimized predicted constitutive model parameters,the modulus E=3.252 MPa and hardness of rubber are deduced to be about 60,which provides guidance for rubber formula design.Second,getting rid of the traditional research and development,i.e.,first thinking the design of structure and then checking the performance.The topology optimization of the three-dimensional tire model is carried out,in which the topology optimization of structure is conducted according to the inspiration from the tooth and gum structures,so a new type of non-pneumatic tire is proposed.The non-pneumatic tire is composed of support column,inner ring,outer ring and tread.Under static grounding condition,the support column of the tire deforms towards the outside of the tire,which is consistent with the deformation mode of the pneumatic tire.The static stiffness curves of the non-pneumatic tire agree well with those of the same size,but the ground pressure distribution of the non-pneumatic tire is more uniform,which can increase the driving comfort and grip of the vehicle,reduce uneven tread wear,and avoid local excessive wear.Third,thermal-structure coupling finite element simulations are carried out for single-lip oil seal under dry friction condition and double-lip oil seal under good lubrication condition,respectively.According to the number of design variables,full-factor test design and optimal Latin hypercube design of experiments are formulated respectively to obtain the influence law of design variables on oil seal performance.According to the results of numerical experiment design,the front lip angle of single-lip oil seal is 47.01°and the rear lip angle of single-lip oil seal is 24°;The optimal structural parameters of double-lip oil seal are 50°front lip angle,24°rear lip angle and 1.4 mm waist thickness.The optimized oil seal has good performance,the maximum contact pressure between the lip and the shaft decreases,and the friction loss between the oil seal lip and the rotating shaft reduces.Such that the maximum temperature in the process of using oil seal decreases,which will reduce the loss of mechanical properties of rubber caused by thermal oxygen aging and improve the service life of oil seal.