Dynamic Tolerance Design Method Of An Aero-engine Rotor System

With the development of science and technology, the rotor system is changing with faster revolution, bigger load and higher temperature, and uncertainty problems become more and more serious. For aero-engine, because of its complex structures, many components, the influence of uncertainty parameters is very significant. Therefore, it's important to deal with uncertainty problems by tolerance design method.In this paper, tolerance design method of rotor dynamic system was investigated, and the process was divided into two stages. In the first stage, the tolerance design theory with noise parameters and its application were studied. The tolerance design method with noise parameters is based on the Taguchi method, which is carried out in a three-step approach, i.e. system design, parameter design, and tolerance design. Taking noise parameters and uncertainties associated with design parameters into account, the reasonable tolerance ranges that balance quality and cost can be obtained. An example of single rotor demonstrated that the vibration response of the system can be suppressed by tolerance design method with noise parameters. What's more, the method was used to the optimization of vibration response of an aero-engine. Given the existence of unbalance in low pressure rotor and uncertainties in bearing stiffness, vibration response of the aero-engine was controlled by way of tolerance design. The results of Monte Carlo simulation indicated that the percent of pass of vibration response had been significantly improved.The second stage focused on test verification of tolerance design theory. The process was divided into two parts. With a single rotor tester as the research object, tolerance design method with noise parameters was validated. The results demonstrated the effectiveness of this method. Then the verification process was introduced into the high pressure rotor system of an aero-engine. The results showed that the aero-engine vibration response can be controlled by way of tolerance design to meet the design requirements.