Study On Tire Thermal Model Based On Two-dimensional Discrete Element

The tire is composed of a variety of rubber and composite materials.When the tire is rolling at high speed,with the viscoelasticity of the rubber material and interaction between tire and the road,it is inevitable to cause a lot of heat in all parts of the tire.Part of the heat accumulated on the tire cannot be dissipated in time,which will cause the temperature of the tire to rise.The increase in tire temperature will cause the deterioration of the physical and mechanical properties such as the tensile strength,fatigue strength,and shear strength of the tire compound.This is an important cause of tire fatigue damage and decreased durability.Therefore,the establishment of a tire thermal model is very important.The establishment of tire thermal models at home and abroad is mostly based on finite element models.Although finite element models can express the temperature field distribution of tires in detail,the establishment of finite element models requires very complicated experiments to determine the thermophysics and mechanical properties of various materials,and the amount of calculation of the finite element model is so large that there is a problem of very low efficiency of simulation.Therefore,this paper establishes a tire thermal model based on twodimensional discrete elements.The main contents of this paper are as follows:First,the thermal model part of the Ftire tire model is introduced.According to the structure of the thermal model and the heat transfer calculation formula of each part,the derivation process of the temperature change of each part of the tire is analyzed..Then this article introduces a thermal model of tire Thermo Racing Tyre based on three-dimensional discrete elements,describes in detail the process of establishing the thermal model and the arrangement and distribution of tire discrete elements,and clarifies the calculation process of heat generation and heat transfer of the model.Then based on the structure and control characteristics of the existing test equipment,a rolling resistance test program for tire thermal analysis was developed.The article first introduces the rolling resistance test bench,infrared thermal imaging camera and other equipment that need to be used in the test,and then describes in detail the specific steps and precautions of the tire rolling resistance test.Finally,the law of the temperature change trend of each part of the tire under the same condition is analyzed in detail,the temperature difference of each part is compared,and main factors affecting the temperature distribution of the tire surface are summarized.Then combined with the tire discrete modeling method,the whole process of the thermal model construction in this article is introduced.First,the structure of the tire thermal model constructed based on two-dimensional discrete elements is given,and then the discrete element model model is used to calculate the respective heat generation of each part of the tire.Combine the heat conduction relationship of each part of the tire this part of the heat is used in the thermal balance equation of each discrete element of the tire,and the calculation formula of the discrete element temperature is dirived,and finally the thermal model of the tire is obtained.Finally,the parameter identification process of the tire thermal model is introduced..First,the dynamic parameters of the tire discrete element model are identified by using the test data of the dynamic mechanical characteristics of the tire rolling over the bump at high speed..Then the tire surface temperature measured in the tire rolling resistance test is used to identify the parameters of the tire thermal model.Finally,the tire thermal model obtained after parameter identification is used for simulation,and the simulation results are compared with the original data of the tire surface temperature to verify the accuracy of the tire thermal model.