Study on the characteristics of Trimaran's surf-riding in stern waves by a hybrid method. (1st December 2022)

• Record Type: Journal Article
• Authors: Gong, Jiaye; Li, Yunbo; Fu, Zheng; Li, Ruipeng; Hong, Zhichao
• Is Part Of: Ocean engineering. Volume 265(2022)
• Publication Date: 2022-12-01
• Subjects: Hybrid method -- Trimaran -- Stern waves -- Navigation -- Wave celerity; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2022.112603
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: In this paper, a hybrid method coupling potential flow method and viscous flow method is applied to simulate the autopilot trimaran in stern waves. The aim is to study the process of being captured by waves and the surf-riding characteristics of the trimaran. The FNPT-based QALE-FEM is used to simulate the wave tank of the external field, and the viscous flow method is used to simulate the autopilot of the trimaran in the wave tank. The sailing and 6DOF motion of the trimaran in waves of different parameters is simulated. The autopilot of a trimaran in stern waves of different lengths and steepness is simulated to study the characteristics of the trimaran's surf-riding in waves. When studying the effect of wave steepness, the wavelength is constant, and various forward speeds of trimaran could change the encounter frequency. However, the trimaran's wave steepness and forward speed are kept constant when the wavelength changes. By the computed results, it is found that the high speed and large wave steepness could significantly increase the vulnerability of trimaran's surf-riding in stern waves, and the wave passing the transom stern and side hulls could accelerate the trimaran to reach the wave celerity. Highlights: A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate the navigation of trimaran in stern waves. An external domain by FNPT-based QALE-FEM is used to simulate a numerical wave tank. An internal domain by viscous flow method is used to simulate the trimaran's autopilot with the 6DOF motion taken into account. By numerical simulation of the trimaran's autopilot in stern waves, the effect of the wave steepness, wavelength and initial speed of the trimaran on the surf-riding of trimaran was studied. The process of the trimaran's motion in stern waves during the surf-riding was obtained, and the phenomenon before and after the surf-riding is analyzed by changing the wave celerity and trimaran's initial speed.