전산유체역학을 이용한 굴 어초의 형상 및 성장에 따른 주변 흐름장 특성 예측

Abstract

Over the past 100 years, ~85% of oysters in the world have been lost due to overfishing, seawater pollution, and climate change. Oyster reefs have many advantages such as stabilizing water quality, protecting shorelines, and providing spawning spaces and shelters for various aquatic creatures. To be a successful oyster restoration project, it is important to figure out the flow characteristics surrounding the oyster reef. However, the structural characteristics of oyster reefs are difficult to predict because they grow in dense spaces and provide excellent attachment surfaces to other organisms. Such difficulties are obstacles in quantifying the structural characteristics of the oyster reef and identifying the characteristics of the surrounding flow field. In this study, I attempted to predict the surrounding flow field and structural characteristics of oyster reefs by assuming the initial models and growth models. To this end, various oyster reefs were modeled and CFD analysis was performed to visualize their three-dimensional wake volumes. Subsequently, the effect of the structural characteristics of oyster reefs on the wake volume was analyzed with proposed indices: efficiency index, improved blocking index, surface complexity index, and normalized wake volume. As a result, the efficiency index increased as the number of oyster shells increased. Furthermore, the normalized wake volume increased as the improved blocking index and surface complexity index increase. This means that there is a correlation between the wake volume and the proposed index representing the structural characteristics of oyster reef (i.e., volume, substrate surface, projection area).