Intensively Stacked Placement Models of Artificial Reef Sets Characterized by Wake and Upwelling Regions

摘要

The wake and upwelling regions of artificial reefs (ARs), and sets, groups, and complexes thereof, are critical factors in engineering AR design and estimating fishing grounds, which are often facilitated by ARs. This study proposes six AR set placement models, constructed based on previous field observations, to characterize their wake and upwelling regions quantitatively through an element-based finite-volume method. These AR sets are hexahedral (Hexa), rectangular (Rect), pyramidal (Pyra), trigonal (Tri), tetragonal (Tetra), and pentagonal (Pent) sets, and their usable volumes are all fixed at 800 m(3) (the minimum requirement of South Korean AR provision) in the flow analysis models. The analyses showed that Rect and Hexa provide the largest wake volumes of 496 and 352 m(3), respectively, while Rect and Tetra provide the largest upwelling volumes of 13,106 and 6,116 m(3), respectively. Finally, the maximum reductions in the wake and upwelling regions due to uniform settlement of 20%, which is equivalent to a usable volume loss of 160 m(3), were 67% and 35%, respectively. Thus, wake regions are more sensitive to usable volume loss than upwelling regions.