Print Email Facebook Twitter Numerical Simulations of Effects of the Layout of Permeable Pile Groin Systems on Longshore Currents Title Numerical Simulations of Effects of the Layout of Permeable Pile Groin Systems on Longshore Currents Author Zhang, R. (TU Delft Coastal Engineering; Hohai University) Chen, Y. (Hohai University) Yao, P. (Hohai University) Stive, M.J.F. (TU Delft Coastal Engineering) Zeng, Jian (Zhejiang Institute of Marine Planning and Design) Date 2023 Abstract Coastal permeable groins have been used to protect beaches from erosion for centuries. However, the hydraulic functioning of permeable groins has not been fully understood and their design heavily depends on engineering experiences. In this study, numerical experiments were executed to investigate the effects of layout configurations of a permeable groin system on longshore currents. The non-hydrostatic SWASH (Simulating WAve till SHore) model was employed to carry out the numerical simulations. Two data sets obtained from physical laboratory experiments with different permeable groin layouts on different slopes are used to validate the accuracy of the model. Then, the longshore current reduction by the permeable groin system with varying configuration parameters (e.g., groin spacing, groin length) was numerically investigated under different environmental conditions (e.g., a slight or a moderate wave climate). From the calculation results of numerical experiments, it is indicated that permeable groins function efficiently to reduce the maximal longshore current velocity under the condition that the groin length ranges from 84% and 109% of the wave breaker zone width. The longshore current reduction rate monotonously decreases with the increase in groin spacing; permeable pile groin functions best to reduce longshore current with the minimal groin spacing-groin length ratio 1:1 among the range between 1:1 and 2:1. When the groin spacing–groin length ratios are 1:1 and 1.5:1, the longshore current reduction is not sensitive to the investigated wave conditions in this study. When the spatial ratio is 2:1, the permeable pile groin system functions worse under a moderate wave climate than under a slight wave climate, from the view of longshore current reduction. Subject permeable pile groinlayout designSWASHlongshore currentlongshore current reduction To reference this document use: http://resolver.tudelft.nl/uuid:4b2f5aed-c520-4120-894f-dedd897bc4db DOI https://doi.org/10.3390/jmse11091823 ISSN 2077-1312 Source Journal of Marine Science and Engineering, 11 (9) Part of collection Institutional Repository Document type journal article Rights © 2023 R. Zhang, Y. Chen, P. Yao, M.J.F. Stive, Jian Zeng Files PDF jmse_11_01823.pdf 4.01 MB Close viewer /islandora/object/uuid:4b2f5aed-c520-4120-894f-dedd897bc4db/datastream/OBJ/view