超弹性SMA复合阻尼器的计算模型及参数分析

Mechanical model and parameter analysis of superelastic SMA compound damper

介绍了超弹性SMA复合阻尼器的构造及工作原理,并根据它的受力特性,建立了该阻尼器的力学计算模型,针对模型中的关键参数:阻尼器内滑条槽深与接触面摩擦系数、SMA丝的预应变及缠绕量、环境温度及位移幅值等对阻尼器力学性能的影响规律进行了分析。分析结果表明:阻尼器的初始刚度、输出力和滞回面积随内滑条槽深、SMA丝缠绕量、接触面的摩擦系数的增加而增加;在不同的位移幅值下,阻尼器的荷载-位移曲线形状分别呈三角形、四边形和五边形等多边形形式,表现为变刚度的特性;阻尼器的屈服位移和输出力随环境温度的升高而线性增加;当对SMA丝施加一定的初始预应变,SMA复合阻尼器表现为摩擦型阻尼器。最后,将模型结果与实验结果进行了对比,两者基本吻合。

The construction and working principle of a superelastic SMA compound damper is introduced. Based on the damper's mechanical behavior, its mechanical model is established. The effects of parameters such as the groove's depth of the inside slip block, friction coefficient between contact surfaces, the prestrain and amount of SMA wires, environmental temperature and displacement amplitude, on the damper mechanical behaviors are analyzed. The results show that, initial stiffness, export force and dissipated energy of the SMA damper increase linearly with groove' depth, SMA wire amount and friction coefficient. Under different displacement amplitude, the shape of the load-displacement curve of SMA damper is polygon such as triangle, quadrangle, pentagon etc, respectively. The SMA damper is a variable stiffness' damper. The yield displacement and export force of damper have linear increase with environmental temperature. Applying certain initial prestrain to SMA wires, the SMA compound damper becomes a friction type damper. In the end, compared with the experiment, the results obtained from the model are in good agreement.