Hydrodynamic interactions in midwater trawl nets: combined effects of flow velocity and door spreading through numerical and experimental approaches
Volume
77
Issue number
1
Article number
77102
Received
27 March 2025
Received in revised form
20 July 2025
Accepted
19 August 2025
Available online
2 September 2025
Authors
Zhao Cheng1, Xiaobin Li1, Yonghe Xie2, Panpan Jia1, Li Guoqiang1,2, Wang Wei2*
1School of Naval Architecture, Ocean and Energy Power Engineering, Wuhan University of Technology, Wuhan 430063
2School of Naval Architecture and Maritime, Zhejiang Ocean University, Zhoushan 316022
Corresponding author email
Abstract
Owing to escalating fuel costs and dwindling fish stocks, optimising midwater trawl efficiency requires a thorough investigation of net design variables. To understand the morphological changes in a trawl net under different operating conditions, a numerical model of the trawl was established using the lumped-mass method. The effects of door spread and flow velocity on trawl morphology, drag force, and energy consumption coefficients were analysed. A generalised additive model was employed to predict the net configuration. In addition, the net mouth parameters of the trawl net were measured using scale model tests in a towing tank and full-scale sea trials to verify the reliability of the predicted results. This study provides guidelines for improving the geometric performance and catchability of midwater trawls.
Keywords
Midwater trawl, Lumped mass method, Towing experiment, Sea trial