Rotordynamic force estimation of turbulent, annular seals using OpenFOAM®


3D CFD simulations are performed to resolve the leakage rates, axial pressure drops, and dynamic force coefficients of smooth annular seals. Simulations are performed for several, simple annular seal geometries subject to water and gas flows in order to verify and validate the open-source CFD library OpenFOAM for such applications. Rotordynamic force coefficients are determined using the whirling-rotor method. Accuracy of CFD-predicted results is assessed through direct comparison with published experimental data and bulk-flow model predictions. For the three water seals analyzed, the open-source, CFD-predicted dynamic coefficients closely agree with their experimental counterparts. The k-\(\omega \) family of turbulence models is shown to outperform the k-\(\epsilon \) models. For the gas seals, the open-source CFD solver is shown to be unsatisfactory in predicting damping coefficients and simulations are alternatively performed with ANSYS Fluent.

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This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 754462.

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Correspondence to Troy Snyder.

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See Table 7.

Table 7 Mesh parameters tested for Kanki seal 1 [50]. r is the inflation layer growth ratio and \(y^+\) values are rotor averages evaluated using OpenFOAM post-simulation

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Snyder, T., Santos, I. Rotordynamic force estimation of turbulent, annular seals using OpenFOAM®. J Braz. Soc. Mech. Sci. Eng. 43, 119 (2021).

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  • Annular seal
  • Rotordynamics
  • CFD
  • OpenFOAM
  • Bulk-flow model