Development of a rotor balancing tool for aeronautical engine application

Rotor's unbalance is a synchronous dynamic load which is source of vibrations, especially on Aircraft engines. These vibrations could lead to hardware failure because of High Cycle Fatigue and it could impact the overall performance of the machine, with even the possibility of a catastrophic event in case the rotor operates at one of its critical speeds. The main goal of rotordynamic analysis is to study the effects of rotor unbalance, predicting and optimizing the modal response of the machine and verifying it through measurements of the resulting vibrations. Residual unbalance is intrinsic of any rotor assembly process and cannot be completely removed. In order to reduce the vibration response, the residual unbalance should be minimized through a dedicated balancing process. This thesis work, done in association with Avio Aero, is focused on the study of the balancing process, with the final goal of developing a tool that is able to perform all the necessary steps. Starting from available field test performed on a turboprop engine, measured vibrations from different trial configurations are analyzed and processed to find how the engine react to a certain weight change. These data are then elaborated by the tool in order to find the best balance solution for the propeller, which is one of the main sources of unbalance in the turboprop engine applications.