Interactions in the rotor‑bearings‑support structure system of the multi‑stage ORC microturbine

  • Grzegorz Żywica
  • Łukasz Breńkacz
  • Paweł Bagiński
Purpose This article discusses the dynamical analysis of the rotating system of a multi-stage vapour microturbine designed to operate in a combined heat and power plant (ORC-based) with rated electrical capacity of 100 kW. The aim of the conducted research was to check the impact of individual components on the dynamics of the prototypical microturbine and to identify the interactions occurring between them. Methods Besides the research carried out on a high-speed rotor and bearings, the analysis also took into account dynamic properties of the machine support structure consisting of a casing, steel base platform and a frame. The numerical computations also covered the vibrations of asynchronous generator connected to the microturbine shaft by a belt transmission gear. The analysis was conducted using both commercial and in-house developed software. This allowed the inclusion of some specific factors of a structural and operational nature (affecting dynamic performance characteristics of the tested machine) into the model. Results On the basis of the results obtained, the dynamic properties of the rotor-bearing-supporting structure systems have been evaluated. The unfavourable dynamical phenomena were observed, which can affect the operation of the machine and lead to damage during its normal operation. Conclusion Based on the outcomes of numerical analysis the diagnostics system dedicated to the ORC microturbine has been developed. Such a system is necessary due to the possibility of the occurrence of dangerous dynamic problems during the machine’s operation.
Type of Publication:
Rotor dynamics; Microturbine; ORC systems
Journal of Vibration Engineering & Technologies