Vortex shedding modes around oscillating non-uniform double heave plates

Abazari, A ; Sharif University of Technology | 2020

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  1. Type of Document: Article
  2. DOI: 10.1177/1475090220966910
  3. Publisher: SAGE Publications Ltd , 2020
  4. Abstract:
  5. Multiple co-axial heave plates of uniform geometry are attached to offshore platforms for inducing damping and added mass. These effects generally decrease the magnitude of the dynamic response of the platform under applied environmental excitation forces. When spacing between heave plates is decreased the damping and added mass performance are altered due to their strong vortex interaction. A new non-uniform plate configuration is proposed that may create different hydrodynamic characteristics. The modes of vortex shedding around plate edges in a non-uniform arrangement under forced harmonic oscillation are investigated via the CFD method. Furthermore, a new simplified formula for the total theoretical added mass of a general non-uniform double disk is proposed when it is in the zone which vortex interaction take places. The results show that a non-uniform double disk has better hydrodynamic performance as compared to the uniform double configuration for a given spacing. It is also observed that the mode and direction of the vortex shedding are different for uniform and non-uniform arrangements in a given spacing and KC value. © IMechE 2020
  6. Keywords:
  7. CFD simulation ; Heave plate ; Hydrodynamic coefficients ; Non-uniform arrangement ; Vortex interaction ; Vorticity ; Damping ; Hydrodynamics ; Offshore oil well production ; Offshore structures ; Vortex shedding ; Forced harmonic oscillations ; Hydrodynamic characteristics ; Hydrodynamic performance ; Nonuniform plate ; Off shore platforms ; Simplified formula ; Vortex interactions ; Vortex-shedding modes ; Vortex flow
  8. Source: Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment ; 2020
  9. URL: https://journals.sagepub.com/doi/abs/10.1177/1475090220966910