Abstract:In this study, computational fluid dynamics (CFD) technology was used to study the flow patterns around porous square artificial reefs with different disposal spaces. The aim was to increase our knowledge base of the fish harvesting principles of artificial reefs and the deployment and layout of the artificial reefs in the construction of marine pastures. Four kinds of disposal spaces were used in the study; they were 0.5, 1.0, 1.5, and 2.0 times the height of the reef. Based on the computer numerical simulation technology, the process of water flowing past the two reefs at a speed of 0.8 m/s was simulated, and the flow around the reef was observed. The results show that there were obvious characteristics of slow flow areas, back eddy current areas, upwelling areas, and dead water areas inside and around the porous square artificial reef. The ratio of the maximum upwelling velocity to the inflow velocity of the porous square artificial reef was about 0.95 times. The ratio of the maximum upwelling height to the reef height around the porous square artificial reef is about 2∶1. To some extent, the structure of the artificial reef provides a favorable role for the diversity of flow patterns around the reef. The spacing of the porous square artificial reef has a great influence on the number, size, distribution, and direction of vortices between the two reefs. Within a certain range, the larger the spacing, the larger the vorticity and the wider the distribution range. Beyond a certain range, the vorticity does not increase and the distribution range does not expand. The larger the spacing of the porous square artificial reefs, the larger the influence area of the back eddy current in the X and Y directions is. The results clearly show the flow field effects of artificial reefs with different disposal spaces, which is of great significance to the deployment and layout of artificial reefs under specific conditions.
