VibronRotor, an opensource rotordynamic code: Development and benchmarking

Abstract

Precise prediction of dynamic response is an important first step in the design and troubleshooting of rotating machinery. Utility of the finite element (FE) method in rotordynamics is well entrenched and has translated into many specialized codes for rotor response prediction. Most specialized codes are propriety software with expensive subscriptions which restrict the access for small-scale rotating machinery manufacturers and researchers to these codes and employed algorithms. In contrast, this paper presents the detailed algorithm and benchmarking of an open-source FE code VibronRotor for rotordynamic analysis. FE formulation in code is based on the work of Nelson and McVaugh (1976). Functionalities of the code include Campbell diagram, critical speed map, mode shapes, imbalance response, orbit plots, and instability threshold analysis. An important capability to analyze the stability of closed-loop electromechanical levitation systems is also explained. These analysis tools are described with design insights to enable selection of rotor design parameters for stable operation and failure prevention. VibronRotor is verified with results from an established rotordynamic software and validated with an inhouse-developed rotor test-rig. Open-source development is primarily aimed to support rotating machinery manufacturers and start-ups to design and troubleshoot rotors without expensive reliance on commercial software. VibronRotor is written to run on a free scientific programming language GNU Octave.