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[目的]拖拉机在湿软水田土壤中行驶时的振动特性与在道路上行驶时明显不同,揭示两种不同行驶工况下振动特性的差异,对拖拉机减振方案设计和悬架系统参数优化具有重要的参考价值和实际意义。[方法]通过对湿软水田土壤阻尼分析,获取湿软水田土壤阻尼系数与轮胎阻尼系数间的关系,并建立了轮胎-湿软水田土壤系统模型、拖拉机整车振动模型以及振动特性理论计算模型,用理论分析的方法,以江苏常发集团CF700型拖拉机为研究对象,计算并比较拖拉机行驶在农村未覆盖土路(国标D级路面)和湿软水田土壤中的振动特性。[结果]与农村未覆盖土路(国标D级路面)行驶工况相比,拖拉机在湿软水田土壤中行驶时,机身垂向振动相对于前、后轮的位移传递率分别下降31.4%和23.5%,俯仰振动幅值分别下降29.5%和24.6%。当拖拉机以3~18 km·h-1速度在湿软水田土壤中行驶时,其机身垂向振动加速度和俯仰振动角加速度平均降低33.0%和32.6%,前、后轮动载荷平均降低34.0%和31.2%,座椅安装处垂向振动加速度平均降低32.9%。[结论]研究结果可以为水、旱田两用拖拉机减振系统设计与智能悬架控制提供理论依据。
[Objective] The vibration characteristics of tractor when driving in wet and soft paddy soil are obviously different from those on the road, revealing the difference of vibration characteristics under two different driving conditions. It has the following characteristics for the design of tractor damping scheme and the optimization of suspension system parameters Important reference value and practical significance. [Method] The relationship between soil damping coefficient and damping coefficient of wet-soft paddy field was obtained through the analysis of soil damping in wet-soft paddy soil. The soil model of the wet-soft paddy soil system, the vehicle vibration model of tractor and the theoretical calculation model of vibration characteristics . With the method of theoretical analysis, the CF700 tractor of Jiangsu Changfa Group was used as the research object to calculate and compare the vibration characteristics of the tractor in the soil of uncovered dirt road (national standard D road) and wet soft paddy soil. [Result] Compared with the driving conditions of uncovered dirt road (national standard D grade road) in rural areas, when the tractor ran in wet and soft paddy soil, the displacement transfer rate of fuselage vertical vibration relative to the front and rear wheels decreased by 31.4% and 23.5%, pitch vibration amplitude decreased by 29.5% and 24.6% respectively. When the tractor travels in wet-soft paddy soil at the speed of 3 ~ 18 km · h-1, the vertical vibration acceleration and the pitch vibration acceleration decrease by 33.0% and 32.6% on average, and the average dynamic load on the front and rear wheels decreases by 34.0% % And 31.2% respectively. The vertical vibration acceleration at the seat installation decreased by 32.9% on average. [Conclusion] The research results can provide the theoretical basis for the design of vibration-damping system and intelligent suspension control of dual-purpose tractor in water and dry land.