Research On Simulation Method Of Tire Inflation Pressure Loss Coupled With Temperature Field And Oxidation

The functions of the tire can be fully exerted only under the appropriate inflation pressure.During the service of the tire,the gas inside it will diffuse outward due to the concentration gradient,resulting in a loss of tire inflation pressure.The decrease in tire inflation pressure will increase additional fuel consumption and emissions of carbon monoxide.IPLR is used to evaluate the level of the tire inflation pressure loss.Standard IPLR testing is costly and time consuming.Tire inflation pressure loss model can realize the rapid and accurate prediction of IPLR,which will accelerate the research of optimization schemes.Therefore,it is meaningful to establishing an accurate tire IPLR prediction model.The Permeability coefficients of nitrogen and oxygen in rubber at different temperatures are tested to predict the IPLR.In order to verify the effectiveness of the oxidation method,a numerical solution of the oxygen concentration distribution inside the rubber and an oxygen consumption test were carried out.In addition,the thermophysical parameters of each component rubber of the PCR tire were tested.Due to the hysteresis loss of rubber,heat generation and oxidation will occur on the tires.In order to simulate the IPLR coupling the temperature field and the oxidation reaction,the IPLR simulation method for coupling the rubber oxidation,the IPLR simulation method for coupling the tire temperature field,and the IPLR simulation method coupling of the rubber oxidation and tire temperature field at the same time are proposed.Taking the passenger car radial(PCR 205/55R16)tire as the research object,and build finite element models.Firstly,the oxygen reaction is coupled to the gas diffusion simulation by adding a subroutine to simulate the IPLR at 60?.The results show that the oxidation reaction increases IPLR and changes the oxygen concentration distribution of the tire,and diffusion-limited oxidation occurs.The IPLR tests are performed under 60?,the difference between the experiment and simulation results is less than 5%.The results shows that considering the oxidation reaction improves the prediction accuracy of the IPLR.Secondly,the IPLR under steady-state rolling is simulated.The results show that the IPLR of tire under steady-state rolling is faster than normal temperature and a large amount of gas escapes from the shoulder area.Based on the rubber self-oxidation scheme,a method of rubber oxygen consumption is proposed and the difference between the experiment and simulation results is less than 3%.Based on the IPLR model under steady-state rolling,the oxygen consumption of different components of the tire was calculated.The results show that the component in the shoulder area have the strongest oxygen consumption capacity.Finally,parameters which have impacts on IPLR are studied.The results shows that decreasing the liner ending length,increasing the innerliner gauge in the shoulder area and decreasing the oxygen diffusivity can reduce the IPLR and oxygen consumption in the shoulder area at the same time.