| Traffic noise is the main source of noise pollution. Tire noise accounts for over 70% of the vehicle noise. Once the rolling speed of heavy duty tire above 60km/h, tire noise represents above 30% of the vehicle noise. Recently, the EU tire labeling regulation stipulated clear requirements and specific implementation deadlines on tire noise performance. But at present, 50% of Chinese tires can not reach the requirements of the second phase standard requirement. In addition, in some countries and regions set up trade barrire and the "double reverse" survey of the China’s tires products, which have a huge impact on the development of the tire industry in China. Therefore, studying on the characteristics of the rolling tires noise is of practical significance for the China’s green tire manufacturing and enterprise upgrading.Taking the all steel radial heavy duty truck tire 295/80R22.5WSL60 as the research object, all parts of tire rubber mechniacal properties were obtained by using the extension cycle after tearing method, and selected Yeoh model to define the mechanical properties of the tire rubber material, and the Rebar model was simulated by using the rubber curtain line composite material. Based on which, the three dimensional tire finite element model was eatablished by ABAQUS software. Then, with the use of tire-ground pressure distribution experiment, external contour test experiment and the modal test, the tire finite element model was verified.The camparison analysis of tire free-modal characteristics between modal test and simulated modal was conducted and the results show that there is a good agreement between the natural frequencies and modal shape at the former six modal. Based on which, the tire vibration noise was computed. Firstly, the tire rolling was implemented by ABAQUS/Explicit method. Secondly, the modal participate factors was computed under the radial force extracted from the rolling tire. Lastly, the characteristics of tire vibration noise under the radial force was studied by combining the modal acoustic transfer method and acoustic boundary theroy, which formed an analysis method of predicting tire vibration noise.The influence of different load, rolling speed and inflation pressure on tire vibration noise was analysed, the characteristics of tire radial modal and tire vibration noise frequency function as well as vibration acceleration at the surface of tire tread and sidewall under different using factors were compared. The results show that with the increase of load, rolling speed, the tire vibration noise pressure value increases, which occurs to a positive correlation. With the increase of tire inflation pressure, the tire radial stiffness obviously increases, but there is no obvious correlation to the inflation pressure. That is to say, proper inflation pressure can reduce tire vibration noise pressure.In order to analysis the effect of tire structure parameters on tire vibration noise, the numerical analysis model with different tire carcass contour, tire tread structure, belt structure and tire crown shape was established, the characteristics of tire radial modal and tire vibration noise frequency function as well as vibration acceleration at the surface of tire tread and sidewall under different structure design parameters were compared. The results show that the new non-balanced equilibruim design tire can reduce tire vibration noise. Proper tread structure design parameters can also reduce tire vibration noise. With the optimization of tire belt structures, the vibration accelerate of tire tread and sidewall decreases, and the tire vibration noise pressure was reduced. Furtheremore, with the increase of the tire travel width, the tire vibration nise pressure shows a slight fluctuate and with the increase of the tire travel height, the tire vibration noise pressure decreases.In order to figure out the influnce of tire modal on tire vibration noise characteristics, a tire structure modal acoustic contribution analysis was proposed by combing the tire modal and acoustic contribution methods. Based on which the sound pressure and the phase contribution of tire modal was studied to tire vibration noise under the peak noise frequencies, and the sensitivity modal to the tire vibration noise was figured out by using the amplitude-phase method. The results show that the tire radial modal frequecies,440Hz and 488Hz individual, are the most sensitivity modal to the tire peak vibration nosie.In order to study the relationship between tire structure and sensitivity modals, the effect of different tire structure mass to the sensitivity modal frequencies and generated mass was analized by virtual of sensitivity analysis method. The influece of different tire structures mass on the sensitivity modals’frequencies and generated mass was obtained. Tire tread, sidewall, inner and carcass are the obvious structures that affects the sensitivity modals characteristics, and the tire tread is the most obvious structure that influence sensitivity modals’ frequecies and generated mass.Inspired by the sensitivity analysis results of decreasing tire tread mass can reduce tire vibration noise and combining the geometry and ground feature of the locust pad, the tire tread structure was lightweight redesigned. Compared to the original design, the optimized tire reduces 0.49 kilograms tread mass and 2.74dB tire vibration noise pressure respectively. For other tire performance, the roll residence decrease 2.6%, grip ground increase 1.5%, friction energe loss decrease 8.1%. In other words, the tire vibration noise and other properties of synchronous improvement is realized by the tire tread lightweight design. Then, the mechanism of reducing tire noise was revealed through the panel acoustic contribution analysis. The optimized tire reduces the pressure of the acoustic positive structures and increase the numbers of the nagetive panels, and as the result, the tire vibration noise was resuced. |
PDF Full Text Request