轴承-转子系统是影响旋转机械稳定运行的重要因素之一，被广泛地应用于包括燃气轮机，航空发动机，工业压缩机及各种电动机等机械装置中，在电力、航空、机械、化工、纺织等国民经济领域中起着非常重要的作用。由于转子的振动，造成了工程上很多不必要的损失。因此，对具有轴向约束的多转子系统的动力学研究具有重要的理论意义和实用价值。 本文首先对具有轴向约束的多转子系统进行静力学分析，建立具有轴向约束的多转子系统动力学模型，推导了转子系统的运动微分方程。数值计算结果表明由于轴向约束与力矩的作用，转子系统的静态挠曲发生变化，改变了径向轴承间的负荷分配，从而影响了轴承的刚度和阻尼系数。 关于具有轴向约束的多转子系统的临界转速及模态的研究，首先介绍计算转子系统的临界转速的传递矩阵方法，编写MATLAB临界转速的传递矩阵计算程序，数值分析结果表明轴向约束一定程度上提高了转子系统的临界转速。对稳定性的研究，分析了转子系统的特征值，结果表明轴向约束对系统的稳定性有影响，且有改善的趋势。 对具有轴向约束的多转子系统的不平衡响应进行了研究，重点分析了不同运转转速下轴向约束对转子系统各结点振动幅值的影响，结果表明具有轴向约束的转子系统在低转速阶段，对其不平衡响应起到一定程度的抑制作用，但作用很小，不是很显著；随后经过共振区的大幅振动之后，进入相对非常平稳的运转区间，此时轴向约束对于抑制转子系统不平衡响应起到比较大的作用；随着转速的提高，具有轴向约束的转子系统的不平衡响应幅值增加。工程上可以趋利避弊，从分利用轴向约束对转子系统作用。

Bearing-rotor system is the most vital component of large rotating machinery. It is widely applied in the machines such as aeroengines, industrial compressors and electromotors. It plays an important role in national economic fields, for example: power, aviation, machine, chemistry, spin and so on. Because the vibration of rotors bring plenty expense which can be avoided, it is of significance to research dynamics of multi-rotor system with axial constraint. Firstly, the dissertation analyzes statics speciality of multi-rotor system with axial constraint. Multi-rotor dynamic model with axial constraint is set up and the differential equations are deduced. The results show that static state flexibility and load distribution among the bearings are influenced on the effect of axial constraint, and then stiffness and damper coefficient are changed. The study on critical speed and mode, transfer matrix method is recommended, and a MATLAB program is designed. The conclusions indicate that axial constraint improves critical speed of rotor system. The study on stability, the conclusions illuminate that axial constraint meliorates stability of rotor system. Influences on the amplitude of the unbalanced response are emphatically analyzed. The results are as follows. At the low speed moment of rotor system axial constraint can control unbalance response, but it is not remarkable. After great amplitude of sympathetic vibration region, axial constraint controls unbalance response and it is very prominent. With improving speed, axial constraint can also impact on the balance of the rotor system to a certain extent. We can fully make use of the function of axial constraint in engineering application.