Structural design and stress analysis of a high-speed turbogenerator assembly supported by hydrodynamic bearings

  • Rodrigo T. BentoEmail author
  • André Ferrus Filho
  • Marco A. Fumagalli
Technical Paper


Turbine and bushing bearing are the most critical components of high-speed machines. This paper describes the design of a high-speed turbine supported by hydrodynamic bearings. The mathematical dimensioning and the FEM analysis are presented to validate the mechanical strength of the turbine and the bushing bearing models. Fatigue life and factor of safety are also determined. The simulations show that the maximum von Mises stress values obtained are associated with the centrifugal force generated by the system rotational movement. The results variation is mainly due to the properties of the materials proposed. For the turbine, 7075-T6 aluminum alloy and SAE 4340 steel obtained satisfactory behavior under a constant operating speed of 30,000 RPM. For the hydrodynamic bearing, the TM23 bronze alloy exhibited excellent results, without fracture, and low mechanical deformation. The models exhibited a great potential employment in several applications, such as biogas systems to generate electrical energy, and educational test bench for thermodynamic and tribological simulations.


High-speed machines Structural design Steam turbine Hydrodynamic bearings FEM analysis 

List of symbols


Coefficient of dynamic friction

Turbine full-arc


Blades theoretical velocity


Mean blade diameter


Dynamic friction force


Normal force


Input enthalpy


Output enthalpy

Mass flow


Internal efficiency


Mechanical efficiency


Mean radius of blades length


Tangential velocity


Mean velocity coefficient



Number of blades


Minimum number of blades


Specific internal work


Coefficient of laminar steam flow


Angular velocity


Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.


  1. 1.
    Hamann T (2014) Perovskites take lead in solar hydrogen race. Science 345:1566–1567. CrossRefGoogle Scholar
  2. 2.
    Lamas W, Giacaglia G (2013) The Brazilian energy matrix: evolution analysis and its impact on farming. Energy Policy 63:321. CrossRefGoogle Scholar
  3. 3.
    Lima LP, Ribeiro GBD, Perez R (2018) The energy mix and energy efficiency analysis for Brazilian dairy industry. J Clean Prod 181:209–216. CrossRefGoogle Scholar
  4. 4.
    Maia TAC, Faria OA, Barros JEM, Porto MP, Cardoso Filho BJ (2017) Test and simulation of an electric generator driven by a micro-turbine. Electr Power Syst Res 147:224–232. CrossRefGoogle Scholar
  5. 5.
    Rosa FC, Lima F, Fumagalli MA (2017) A high-speed shaft supported by magnetic bearings applied to energy systems. J Braz Soc Mech Sci Eng 39:29–39. CrossRefGoogle Scholar
  6. 6.
    Paniagua G, Iorio MC, Vinha N, Sousa J (2014) Design and analysis of pioneering high supersonic axial turbines. Int J Mech Sci 89:65–77. CrossRefGoogle Scholar
  7. 7.
    Machado TH, Cavalca KL (2015) Modeling of hydrodynamic bearing wear in rotor-bearing systems. Mech Res Commun 69:15–23. CrossRefGoogle Scholar
  8. 8.
    Zhay L, Liu X, Chen F, Xiao Y, Wang Z (2014) Numerical simulations for the fluid-thermal-structural interaction lubrication in a tilting pad thrust bearing. Eng Comput 34:1149–1165. CrossRefGoogle Scholar
  9. 9.
    Melconian S (2011) Elementos de máquinas. Érica, São PauloGoogle Scholar
  10. 10.
    Chasalevris AC, Nikolakopoulos PG, Papadopoulos CA (2013) Dynamic effect of bearing wear on rotor-bearing system response. J Vib Acoust 135:011008. CrossRefGoogle Scholar
  11. 11.
    Zhay L, Luo Y, Wang Z, Liu X (2016) 3D two-way coupled TEHD analysis on the lubricating characteristics of thrust bearings in pump-turbines by combining CFD and FEA. Chin J Mech Eng 29:112–123. CrossRefGoogle Scholar
  12. 12.
    Usman A, Park CW (2018) Numerical optimization of surface texture for improved tribological performance of journal bearing at varying operating conditions. Ind Lubr Tribol 70:1608–1618. CrossRefGoogle Scholar
  13. 13.
    Nguyen VD, Jansson J, Goude A, Hoffman J (2019) Direct finite element simulation of the turbulent flow past a vertical axis wind turbine. Renew Energy 135:238–247. CrossRefGoogle Scholar
  14. 14.
    Komori M, Hara K, Asami K, Sakai N (2018) Trial of superconducting magnetic bearings applied to high-speed turbine rotor. IEEE Trans Magn 54:1–4. CrossRefGoogle Scholar
  15. 15.
    Rezaei MM, Zohoor H, Haddadpour H (2018) Aeroelastic modeling and dynamic analysis of a wind turbine rotor by considering geometric nonlinearities. J Sound Vib 432:653–679. CrossRefGoogle Scholar
  16. 16.
    Yao J, Liu L, Yang F, Scarpa F, Gao J (2018) Identification and optimization of unbalance parameters in rotor-bearing systems. J Sound Vib 431:54–69. CrossRefGoogle Scholar
  17. 17.
    Arakawa K (2014) Effect of time derivative of contact area on dynamic friction. Appl Phys Lett 104:241603. CrossRefGoogle Scholar
  18. 18.
    Kiehl M (2001) Einführung in die DIN-Normen. Springer, Berlin. CrossRefGoogle Scholar
  19. 19.
    Askeland DR, Fulay PP, Wright WJ (2010) The science and engineering of materials. CENGAGE Learning, São PauloGoogle Scholar
  20. 20.
    Callister WD Jr, Rethwisch DG (2009) Material science and engineering: an introduction. Wiley, New YorkGoogle Scholar
  21. 21.
    Ji DM, Sun JQ, Dui Y, Ren JX (2017) The optimization of the start-up scheduling for a 320 MW steam turbine. Energy 125:345–355. CrossRefGoogle Scholar
  22. 22.
    Li H, Li J, Yuan H (2018) A review of the extended finite element method on macrocrack and microcrack growth simulations. Theor Appl Fract Mech 97:236–249. CrossRefGoogle Scholar
  23. 23.
    Kumar D, Sarkar S (2016) Numerical investigation of hydraulic load and stress induced in Savonius hydrokinetic turbine with the effects of augmentation techniques through fluid-structure interaction analysis. Energy 116:609–618. CrossRefGoogle Scholar
  24. 24.
    Madhu P (2016) Stress analysis and life estimation of gas turbine blisk for different materials of a jet engine. Int J Sci Res 5:1103–1107. MathSciNetCrossRefGoogle Scholar
  25. 25.
    Termomecanica São Paulo S.A, Bronze alloys catalogue. Accessed 9 Nov 2018

Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2019

Authors and Affiliations

  1. 1.Nuclear and Energy Research Institute, IPEN–CNEN/SPUniversity of São PauloSão PauloBrazil
  2. 2.Universidade São Judas TadeuSão PauloBrazil
  3. 3.Faculdade de Tecnologia TermomecanicaSalvador Arena FoundationSão Bernardo do CampoBrazil

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