Joerot rotor dynamics toolbox based on complex transfer matrix method

Abstract

The demand for high-speed and high-precision lightweight rotors increases with the need for high-performance industrial machines. To manufacture such precision rotors, engineers are pushed to perform more detailed design analyses using the science of rotor dynamics. However, commercial rotor dynamics software that performs these analyses has high prices. In addition, the closed source code prevents the researcher from developing subroutines to work with their test data. These limitations in commercial software prevent researchers from solving unique rotor dynamics problems. For this reason, researchers around the world have been developing their rotor dynamics software based on the Finite Element Method (FEM). In this study, an in-house-developed & open-source rotor dynamics toolbox named JoeRot is developed based on the Complex Transfer Matrix Method (CTMM). The proposed toolbox can perform analyses faster than the FEM and allows modeling and solving unique rotor dynamics problem such as unbalance response. Various analyses such as plotting the Campbell diagram, finding natural frequencies, determining mode shapes, determining the system frequency response due to unbalance, instability threshold analysis, and plotting a critical velocity map can be carried out on the designed toolbox. To investigate the accuracy of the JoeRot toolbox, a comparison is made between the analytical method and the finite element method. As a result of this comparison, it is observed that natural frequencies and deflection frequency response values were obtained under a 0.46% error rate and 22.75 times faster than other compared methods.