Numerical prediction of cavitation erosion to investigate the effect of wake on marine propellers


Köksal Ç. S. , Usta O., Aktas B., Atlar M., Korkut E.

OCEAN ENGINEERING, vol.239, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 239
  • Publication Date: 2021
  • Doi Number: 10.1016/j.oceaneng.2021.109820
  • Title of Journal : OCEAN ENGINEERING
  • Keywords: KCD-193 propeller, RANS, DES, Cavitation modelling, Cavitation erosion prediction, Erosive power method (EPM), CFD SIMULATIONS

Abstract

This paper presents validation studies to simulate performance, cavitation and cavitation erosion properties of the King's College (KCD) KCD-193 model propeller. The simulations are performed to investigate the effect of wake on the cavitation formation and the cavitation erosion intensity. The numerical (CFD) study is achieved by using unsteady Reynolds Averaged Navier-Stokes (RANS) and Detached Eddy Simulation (DES) techniques with SST (Menter) k-omega turbulence model. The Schnerr-Sauer cavitation model and Eulerian approach with the Volume of Fluid (VOF) multiphase model are used to model a two-phase cavitation flow. The sliding mesh technique is applied to simulate the rotation of the propeller, and particular mesh refinement is performed on the regions where cavitation development is observed. Erosion intensity values on the propeller surface are obtained by Erosive Power Method (EPM) approach, and erosion formation on the blades is illustrated by utilizing the erosion intensity dataset. Numerical comparison for the erosion intensity values using RANS and DES models is carried out to evaluate the effect of wake in behind condition. Numerical results are evaluated against cavitation tunnel measurements at the Emerson Cavitation Tunnel (ECT) of Newcastle University. The main objectives of the study are to obtain the cavitation and cavitation erosion formation on the propeller in good agreement with experimental data obtained in ECT and to investigate the characteristics of the erosion intensity subject to cavitation conditions. In view of the flow conditions investigated, the RANS model is also found appropriate and required less computing efforts to predict the erosion intensity than the DES model. The results confirm the EPM method is to be compatible in predicting the erosion intensity. The results of the simulations indicate that a decrease in cavitation number does not necessarily cause an increase in the erosion intensity, requiring further investigation.