Study on the power flow transmission characteristics of Roots blower

In this paper, according to the serious vibration and noise problem of Roots blower and based on the vibration energy transmission, a simplified dynamics model was set up which consist of five sub-structures such as rotor, bearing, box, vibration isolator and flexible foundation. The Lim model of elastic bearing was used, the rotor shaft and box were considered as rigid body, and the foundation was simplified a flexible sheet. The dynamic transferring matrix of blower sub-structure were derived using the method of component mobility, and then a spatial flexible couple dynamics model was established. As an example, the vibration characteristics of Roots blower were studied with the power flow method, and the numerical calculation and simulation of a sample were carried out. The analysis results showed that the influence of structural parameters, such as bearing stiffness, isolator stiffness, foundation stiffness and box mass, were more distinctly on the dynamics characteristics of Roots blower, which paid an important theory base for structure optimization and dynamic design.