Vibration Suppression of Additional Unbalance Caused by the Non-continuous Characteristics of a Typical Aero-Engine Rotor

The advanced aero engines have various features such as light weight, high efficiency and high power, so its rotor system is comparably weak, while the rotor often has to endure heavier weight loads. With loads of assembling and operating, the relative position between jointing interfaces will variate due to the relative slide of the interfaces and the changes of contact status. Dislocation of jointing interfaces can induce a deviation of the center of mass (CM) of the rotor system from its rotating axis, which implies an additional unbalance and may cause an engine vibration problem. In this article, a mechanism model is established to study the random influence of joints over the unbalance of rotor system. Then researchers use a typical aero-engine rotor as an example to investigate this topic. This study indicates that the additional unbalance of rotor system can be ascribed to the relative dislocation between jointing interfaces. The additional unbalance also shows a strong uncertainty due to the randomness of interfaces' dislocation. Methods to control the technological parameters of joints should be utilized during the designing span of a rotor system in order to significantly depress the unbalance of rotor system and prevent engine from vibration effectively.