Zhiyu Zou , Yonggang Zhao , Lulu Yue , Yifan Qi , Shicheng Hu , Wei Fan
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引用次数: 0
Abstract
Coral reefs, critical marine ecosystems threatened by escalating sea surface temperatures, demand innovative solutions to mitigate thermal stress. This study introduces a novel Well-Upwelling (WU) system that strategically injects chilled seawater to form a three-dimensional cooling umbrella over coral habitats. Nozzle parameters and layouts are optimized by leveraging computational fluid dynamics (CFD), machine learning (ML), and a hybrid Particle Swarm Optimization (PSO-DPSO) framework. Categorical Boosting (CatBoost) was validated as superior for predicting jet dynamics, enabling efficient optimization of nozzle diameter (d0), exit velocity (u0), and discrete layouts. A case study near Nanshan Harbor, China—where severe heat stress occurred in 2024 (Degree Heating Weeks, DHW > 8)—revealed that the integrated PSO-DPSO algorithm improved cooling efficiency by 17.8–46.1 % compared to random layouts, identifying optimal parameters (u0 = 0.20 m/s, d0= 0.21 m) that balanced efficiency and thermal retention. Notably, the simulation-based results indicate that the optimized system reduced the DHW value during the study period from 1.83 to 0.45 in the coral region, corresponding to a 1.38±0.073℃ decrease in average temperature—below the threshold (DHW = 1) that induces visible coral stress. This work establishes a scalable, data-driven framework for hydrodynamic optimization, demonstrating the WU system’s potential to mitigate coral bleaching by effectively reducing thermal stress in dynamic marine environments.
期刊介绍:
The aim of Applied Ocean Research is to encourage the submission of papers that advance the state of knowledge in a range of topics relevant to ocean engineering.