Abstract
Submersible fish cages can be submerged under the water to mitigate the negative effects that arise from severe sea conditions and improve the growing environment for the farmed fish. Thus they are increasingly applied in offshore aquaculture. To ensure both safety and economic efficiency of submersible fish cages, it is important to determine the optimum submergence depth. In this study, a series of physical model experiments were conducted to investigate the hydrodynamic performance of a submersible fish cage at various submergence depths (1/6, 1/4, 1/3, and 1/2 of the water depth as well as the floating condition for reference) with a model scale of 1:20. The results of the physical model experiment for the different depths were compared to analyze the effects of submergence depths on the mooring line tension and the movement of the floating collar. The results showed that the mooring line tension and the floating collar movement significantly attenuated with increasing submergence depth. However, the attenuation tendency became stable when the fish cage reached a certain depth. According to the results, 1/3 of water depth was determined as the optimal submergence depth of the fish cages. Deeper submergence depths showed no significant advantage from a perspective of the hydrodynamic characteristics of the fish cage. The determination of the optimum submergence depth is beneficial for the structural design and operation safety of submersible net cages.
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References
Bi, C. W., Zhao, Y. P., and Dong, G. H., 2015. Numerical study on the hydrodynamic characteristics of biofouled full-scale net cage. China Ocean Engineering, 29: 401–414.
Celikkol, B., Baldwin, K., Steen, R., Michelin, D., Muller, E., and Lavoie, P., 2000. Open ocean aquaculture engineering: Mooring & net pen deployment. Marine Technology Society Journal, 34: 53–58.
Chen, H., and Christensen, E. D., 2017. Development of a numerical model for fluid-structure interaction analysis of flow through and around an aquaculture net cage. Ocean Engineering, 142: 597–615.
DeCew, J., Fredriksson, D. W., Bugrov, L., Swift, M. R., Eroshkin, O., and Celikkol, B., 2005. A case study of a modified gravity type cage and mooring system using numerical and physical models. IEEE Journal of Oceanic Engineering, 30: 47–58.
DeCew, J., Tsukrov, I., Risso, A., Swift, M. R., and Celikkol, B., 2010. Modeling of dynamic behavior of a single-point moored submersible fish cage under currents. Aquacultural Engineering, 43: 38–45.
Fredriksson, D. W., DeCew, J. C., Tsukrov, I., Swift, M. R., and Irish, J. D., 2007. Development of large fish farm numerical modeling techniques with in situ mooring tension comparisons. Aquacultural Engineering, 36: 137–148.
Goudey, C. A., Loverich, G., Kitepowell, H., and Costapierce, B. A., 2001. Mitigating the environmental effects of mariculture through single-point moorings (SPMs) and drifting cages. Ices Journal of Marine Science, 58: 497–503.
Gui, F., Li, Y., Dong, G., and Guan, C., 2006. Application of CCD image scanning to sea-cage motion response analysis. Aquacultural Engineering, 35: 179–190.
Huang, X. H., Guo, G. X., Tao, Q. Y., Hu, Y., Liu, H. Y., Wang, S. M., and Hao, S. H., 2016. Numerical simulation of deformations and forces of a floating fish cage collar in waves. Aquacultural Engineering, 74: 111–119.
Jin, H., Liu, Y., Li, H., and Fu, Q., 2017. Numerical analysis of the flow field in a sloshing tank with a horizontal perforated plate. Journal of Ocean University of China, 16: 575–584.
Kim, T. H., Hwang, K. S., and Shin, S. S., 2012. Developing of a remotely operated submersible fish cage system. Sea Technology, 53: 45–49.
Kim, T. H., Yang, K. U., Hwang, K. S., Jang, D. J., and Hur, J. G., 2011. Automatic submerging and surfacing performances of model submersible fish cage system operated by air control. Aquacultural Engineering, 45: 74–86.
Loverich, G., and Forster, J., 2000. Advances in offshore cage design using Spar Buoys. Marine Technology Society Journal, 34: 18–28.
Moe-Føre, H., Lader, P. F., Lien, E., and Hopperstad, O. S., 2016. Structural response of high solidity net cage models in uniform flow. Journal of Fluids and Structures, 65: 180–195.
Shi, Y., Li, S., Zhang, H., Peng, S., Chen, H., Zhou, R., and Mao, T., 2017. Numerical modeling of floating oil boom motions in wave-current coupling conditions. Journal of Ocean University of China, 16: 602–608.
Swift, M. B., Fredriksson, D. W., Unrein, A., Fullerton, B., Patursson, O., and Baldwin, K., 2006. Drag force acting on biofouled net panels. Aquacultural Engineering, 35: 292–299.
Tang, H., Hu, F., Xu, L., Dong, S., Zhou, C., and Wang, X., 2017. The effect of netting solidity ratio and inclined angle on the hydrodynamic characteristics of knotless polyethylene netting. Journal of Ocean University of China, 16: 814–822.
Tsukrov, I., Drach, A., DeCew, J., Swift, M. R., and Celikkol, B., 2011. Characterization of geometry and normal drag coefficients of copper nets. Ocean Engineering, 38: 1979–1988.
Winthereig-Rasmussen, H., Simonsen, K., and Patursson, Ø., 2016. Flow through fish farming sea cages: Comparing computational fluid dynamics simulations with scaled and full-scale experimental data. Ocean Engineering, 124: 21–31.
Xu, T. J., Zhao, Y. P., Dong, G. H., and Gui, F. K., 2013. Analysis of hydrodynamic behavior of a submersible net cage and mooring system in waves and current. Applied Ocean Research, 42: 155–167.
Yin, Z., Yang, X., Xu, Y., Ding, M., and Lu, H., 2017. Experimental wave attenuation study over flexible plants on a submerged slope. Journal of Ocean University of China, 16: 1009–1017.
Zhao, Y. P., Li, Y. C., Dong, G. H., Gui, F. K., and Teng, B., 2007. Numerical simulation of the effects of structure size ratio and mesh type on three-dimensional deformation of the fishing-net gravity cage in current. Aquacultural Engineering, 36: 285–301.
Zhou, C., Xu, L., Hu, F., and Qu, X., 2015. Hydrodynamic characteristics of knotless nylon netting normal to free stream and effect of inclination. Ocean Engineering, 110: 89–97.
Acknowledgments
This work was financially supported by the National Natural Science Foundation of China (Nos. 51579037, 51609035, 51822901, 31872610), China Postdoctoral Science Foundation (Nos. 2017T100176, 2016M590224), and the Science and Technology Development Plan Project of Shandong Province (No. 2014GHY115023).
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Liu, S., Bi, C., Yang, H. et al. Experimental Study on the Hydrodynamic Characteristics of a Submersible Fish Cage at Various Depths in Waves. J. Ocean Univ. China 18, 701–709 (2019). https://doi.org/10.1007/s11802-019-3880-z
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DOI: https://doi.org/10.1007/s11802-019-3880-z