Grid Type and Turbulence Model Influence on Propeller Characteristics Prediction

• Main Authors: Ante Sikirica, Zoran Čarija, Lado Kranjčević, Ivana Lučin
• Format: Article
• Language: English
• Published: MDPI AG 2019-10-01
• Series: Journal of Marine Science and Engineering
• Subjects: cfd; open water; cavitation; structured grid; pptc
• Online Access: https://www.mdpi.com/2077-1312/7/10/374

This paper evaluates the applicability of the hexahedral block structured grids for marine propeller performance predictions. Hydrodynamic characteristics for Potsdam Propeller Test Case (PPTC), namely thrust and torque coefficients, were determined using numerical simulations in two commercial solvers: Ansys Fluent and STAR-CCM+. Results were attained for hexahedral and tetrahedral hybrid grids equivalent in terms of cell count and quality, and compared to the experimental results. Furthermore, accuracy of Realizable <i>k</i>-<inline-formula> <math display="inline"> <semantics> <mi>ϵ</mi> </semantics> </math> </inline-formula> and SST <i>k</i>-<inline-formula> <math display="inline"> <semantics> <mi>&#969;</mi> </semantics> </math> </inline-formula> turbulent models when analyzing marine propeller performance was investigated. Finally, performance characteristics were assessed in cavitating flow conditions for a single advance ratio using Zwart&#8722;Gerber&#8722;Belamri and Schnerr and Sauer models. The resulting cavitation pattern was compared to cavity extents and shape noted during measurements. The results suggest that hexa and hybrid grids, in certain range of advance ratios, do provide similar results; however, for low and high ratios, structured grids in conjunction with Realizable <i>k</i>-<inline-formula> <math display="inline"> <semantics> <mi>ϵ</mi> </semantics> </math> </inline-formula> model can achieve more accurate results.