刹车系统摩擦自激振动的数值研究

建立了刹车系统的三自由度动力学方程,采用LuGre模型计算摩擦块、盘之间的摩擦力。通过数值模拟,揭示非内共振摩擦块的复杂动力学行为。研究表明,随着摩擦盘速度减小,切向静平衡状态失稳,依次出现完全滑动和非完全黏滞-滑动的干摩擦自激振动现象。当黏性摩擦系数非常大时,会导致带有非完全黏滞特征的混沌运动。扭转运动的非完全黏滞自激振动中,包含了速度快速抖动现象;而切向和扭转运动是导致低、高频噪声的原因。

Numerical Study on the Self-excited Vibration of Disc Brake System

The dynamical equations for a 3-DOF automotive disc brake system are derived. The LuGre model is adopted to determine the friction force between the disc and the pad. The complex dynamical behavior of the brake pad with non-internal conditions is numerically investigated. It is shown that with the decrease of disc velocity, the tangential motion of the pad loses its stability, and the pure slip and incomplete-stick-slip self-excited vibrations are resulted. As the viscous friction factor becomes quite large, the chaotic motion with incomplete-stick-slip characteristics can be resulted. The pad can vibrate in torsion with high frequency when in incomplete-stick-slip stage. The tangential and the torsional self-excited vibrations lead to low and high frequency squeal noises.