多激励下采煤机在行走平面内的非线性振动特性分析

Nonlinear Vibration of Shearer in Walk Plane Under Multiple Excitation

提出以随机分布的煤岩单轴抗压强度为输入,采用锋利截齿截割阻力方程描述采煤机截割激励,采用间隙条件下齿轮啮合非线性模型描述采煤机驱动轮与销排间行走激励,采用库伦摩擦模型描述采煤机平滑靴、导向滑靴与刮板机间的摩擦激励,再根据拉格朗日动力学方程建立了采煤机7自由度非线性振动模型。利用Newmar k-β法对方程进行了求解,分析了当行走速度为4 m/min,行走驱动轮与销排间隙为6 mm时,采煤机在行走平面内的振动特性,结果表明:行走部和机身的振动特性较为相似,但行走部的振动量小于机身;两个滚筒振动量较大,且右侧滚筒振动量大于左侧滚筒;机身和滚筒的振动相图、庞加莱映射表明采煤机工作过程中处于混沌振动状态。对采煤机振动特性进行了现场实验,实验测得的机身振动加速度有效值接为171.83mm/s^2,接近仿真值(153.06 mm/s^2),实验结果表明采煤机机的非线性模型在一定程度上可以视为准确的。

Based on random distribute of coal rock uniaxial hardness for the input,describing shearer cutting incentives by using the sharp cutter cutting resistance equations,Using gear meshing non-linear model under the condition of clearance described pedestrian excitation between driving gear and pin rail of Shearer,the coulomb friction model was applied to describe friction excitation among shearer smoothing boots,guide foot and scraper conveyor,then according Lagrange dynamic equations set up a 7- DOF nonlinear vibration model of the Shearer,the equation was solved by the Newmark-β method. The shearer＇s vibration characteristics in walk plane was analyzed when the walking speed was 4 m / min and the both sides clearance between the walk driving wheel and the pin rail is 6 mm. The results show that the vibration character of travel unit and fuselage are similar,but the vibration quantity of travel unit is less than fuselage. Vibratory quantity of drum is larger,and the right＇s is larger than the left＇s. Phase Diagram and poincare map of fuselage and drum show that the working shearer is in chaotic state. Field experiment of shearer＇s vibration characteristics are done. Experimental measurements of the effective value of fuselage vibration acceleration is 171. 83 mm / s^2,and is closed to the simulation value（ 153.06 mm/s^2）. The experiment results show that nonlinear model of shearer can be regarded as accurate to some extent