Investigation of dynamic similarity of gear transmission system considering machining error distortion: Theoretical analysis and experiments

• The dynamic similarity relationship of gear transmission system is derived. • The similarity ratio of peak-to-peak value of vibration response is proposed. • Two modification methods of machining error distortion are proposed. • The modification methods are verified by numerical analysis and experiments. Accurate setting of the gear machining error to a certain expected value is a difficult task. A non-ideal value may cause the system to not meet the complete similarity condition and reduce the prediction accuracy of the scale model (SM). In this study, the similarity relationship of a gear transmission system, considering the machining error, was derived using the equation analysis method. To address the problem of machining error distortion, a similarity ratio of the peak-to-peak value of the vibration response, and two modification methods for SM prediction are proposed herein. In the first method, the load is modified, whereas in the second method, the similarity ratio is modified. A node finite-element model and transmission error experiment were used to verify the accuracy of the two methods. The results indicate that the prediction of the changing trend and amplitude of the vibration response was accurate. The modified load method should be used in the design stage for the working conditions, and the modified similarity ratio method should be used in the experimental data processing stage. Graphical Abstract .