Journal of Ocean Engineering and Science

Volume 4, Issue 1

(5)Effects of ﬁxed and dynamic mesh methods on simulation of stepped planing craft

M. Mehdi Doustdar ^∗, Hamid Kazemi

Department of Mechanical Engineering, Imam Hossein University, Tehran, Iran

Received 1 December 2018; received in revised form 22 December 2018; accepted 24 December 2018

Available online 28 December 2018

Abstract

In the present study, we investigate the effects of ﬁxed and dynamic mesh methods on CFD simulation of stepped planing craft. To this accomplishment, three different body forms of without step, one step, and two step Cougar planing crafts are considered. Three-dimensional CFD analysis is conducted using ﬁnite volume method (FVM). Volume of ﬂuid (VOF) model is used for free surface modeling. Overset mesh technique (dynamic mesh) and ﬁxed mesh method are conducted by STAR CCM and ANSYS CFX CFD toolboxes, respectively. CFD results of total hydrodynamic resistance and dynamic trim angle are compared against our measured experimental data to assess the performance and accuracy of considered mesh methods. For more details, pressure distributions, wave patterns and streamlines around the hull models are also presented. Based on our CFD results, dynamic mesh method is more accurate and precise to simulate the stepped planing crafts compared to ﬁxed mesh method. However, computational cost for dynamic mesh method is signiﬁcantly greater than the ﬁxed mesh method. We also found that the porpoising phenomenon is only detectable using dynamic mesh method in simulation of stepped Cougar planing craft. © 2018 Shanghai Jiaotong University. Published by Elsevier B.V.

This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Keywords: CFD; Dynamic mesh method; Fixed mesh method; Stepped planing craft.