“An Integrated Approach to Modelling Fish Cage Response in the Flow”

Authors: Sihan Gao, Lars Christian Gansel, Guoyuan Li and Houxiang Zhang,
Affiliation: NTNU Aalesund
Reference: 2021, Vol 42, No 4, pp. 173-184.

Keywords: fish cage modelling, Morison-type load model, fish cage deformation, fish cage digitalization

Abstract: Noticeable progress has been made in recent years regarding sensor-based monitoring and model-based simulation of sea cage response. The discrepancy between measured data and simulation results can cause confusion about the actual deformation of fish cages. This study aims to explore an approach of integrating measured depth data with a deterministic cage model for sea cage response prediction in dynamic analysis software Orcaflex, emphasizing on cage deformation estimation. A Morison-type cage model is divided into several net panels, regulators based on PID theory are developed and incorporated into the cage model to regulate the hydrodynamic properties of cage net panels based on measured depth. Through a case study based on published model tests, it is shown that the model incorporating measured depth can significantly improve the predictions of cage deformation compared with deterministic models. The resultant drag forces from the integrated models are also with reasonably good accuracy.

PDF PDF (5789 Kb)        DOI: 10.4173/mic.2021.4.3

DOI forward links to this article:
[1] Sihan Gao, Peihua Han, Lars Christian Gansel, Guoyuan Li and Houxiang Zhang (2023), doi:10.1109/ICIEA58696.2023.10241403
[2] Sihan Gao, Chunling Wang, Stig Atle Tuene, Guoyuan Li, Houxiang Zhang and Lars Christian Gansel (2024), doi:10.1016/j.aquaeng.2024.102429
[1] Aarsnes, J., Rudi, H., and Loland, G. (1990). Current forces on cage, net deflection, In Engineering for offshore fish farming, pages 137--152. Thomas Telford Publishing.
[2] Cheng, H., Li, L., Aarsaether, K.G., and Ong, M.C. (2020). Typical hydrodynamic models for aquaculture nets: A comparative study under pure current conditions, Aquacultural Engineering. 90:102070. doi:10.1016/j.aquaeng.2020.102070
[3] Cifuentes, C. and Kim, M. (2017). Hydrodynamic response of a cage system under waves and currents using a morison-force model, Ocean Engineering. 141:283--294. doi:10.1016/j.oceaneng.2017.06.055
[4] Cifuentes, C., Kim, S., Kim, M., and Park, W. (2015). Numerical simulation of the coupled dynamic response of a submerged floating tunnel with mooring lines in regular waves, Ocean Systems Engineering. 5(2):109--123. doi:10.12989/ose.2015.5.2.109
[5] DeCew, J., Fredriksson, D., Lader, P., Chambers, M., Howell, W., Osienki, M., Celikkol, B., Frank, K., and Hoy, E. (2013). Field measurements of cage deformation using acoustic sensors, Aquacultural engineering. 57:114--125. doi:10.1016/j.aquaeng.2013.09.006
[6] Fitridge, I., Dempster, T., Guenther, J., and DeNys, R. (2012). The impact and control of biofouling in marine aquaculture: a review, Biofouling. 28(7):649--669. doi:10.1080/08927014.2012.700478
[7] Fore, H.M., Endresen, P.C., Norvik, C., and Lader, P. (2021). Hydrodynamic loads on net panels with different solidities, Journal of Offshore Mechanics and Arctic Engineering. 143(5):051901. doi:10.1115/1.4049723
[8] Gansel, L., Bloecher, N., Floerl, O., and Guenther, J. (2017). Quantification of biofouling on nets: a comparison of wet weight measurements and optical (image analysis) methods, Aquaculture international. 25(2):679--692. doi:10.1007/s10499-016-0062-5
[9] Gansel, L.C., McClimans, T.A., and Myrhaug, D. (2012). Flow around the free bottom of fish cages in a uniform flow with and without fouling, Journal of offshore mechanics and Arctic engineering. 134(1). doi:10.1115/1.4003695
[10] Gansel, L.C., Oppedal, F., Birkevold, J., and Tuene, S.A. (2018). Drag forces and deformation of aquaculture cages—full-scale towing tests in the field, Aquacultural Engineering. 81:46--56. doi:10.1016/j.aquaeng.2018.02.001
[11] Gansel, L.C., Rackebrandt, S., Oppedal, F., and McClimans, T.A. (2014). Flow fields inside stocked fish cages and the near environment, Journal of offshore mechanics and Arctic engineering. 136(3). doi:10.1115/1.4027746
[12] He, Z., Faltinsen, O.M., Fredheim, A., and Kristiansen, T. (2018). The influence of fish on the mooring loads of a floating net cage, Journal of Fluids and Structures. 76:384--395. doi:10.1016/j.jfluidstructs.2017.10.016
[13] Heffernan, D. (2020). An introduction to the Python interface to OrcaFlex, Technical report. www.orcina.com/.
[14] Klebert, P., Patursson, O., Endresen, P.C., Rundtop, P., Birkevold, J., and Rasmussen, H.W. (2015). Three-dimensional deformation of a large circular flexible sea cage in high currents: Field experiment and modeling, Ocean Engineering. 104:511--520. doi:10.1016/j.oceaneng.2015.04.045
[15] Kristiansen, T. and Faltinsen, O.M. (2012). Modelling of current loads on aquaculture net cages, Journal of Fluids and Structures. 34:218--235. doi:10.1016/j.jfluidstructs.2012.04.001
[16] Lader, P., Dempster, T., Fredheim, A., and Jensen, O. (2008). Current induced net deformations in full-scale sea-cages for atlantic salmon (salmo salar), Aquacultural Engineering. 38(1):52--65. doi:10.1016/j.aquaculture.2018.06.060
[17] Lader, P.F. and Enerhaug, B. (2005). Experimental investigation of forces and geometry of a net cage in uniform flow, IEEE Journal of Oceanic Engineering. 30(1):79--84. doi:10.1109/JOE.2004.841390
[18] Lee, C.-W., Lee, J.-H., Cha, B.-J., Kim, H.-Y., and Lee, J.-H. (2005). Physical modeling for underwater flexible systems dynamic simulation, Ocean engineering. 32(3-4):331--347. doi:10.1016/j.oceaneng.2004.08.007
[19] Loland, G. (1993). Current forces on, and water flow through and around, floating fish farms, Aquaculture International. 1(1):72--89.
[20] Moe, H., Fredheim, A., and Hopperstad, O. (2010). Structural analysis of aquaculture net cages in current, Journal of Fluids and Structures. 26(3):503--516. doi:10.1016/j.jfluidstructs.2010.01.007
[21] Moe-Fore, H., ChristianEndresen, P., GunnarAarsaether, K., Jensen, J., Fore, M., Kristiansen, D., Fredheim, A., Lader, P., and Reite, K.-J. (2015). Structural analysis of aquaculture nets: comparison and validation of different numerical modeling approaches, Journal of Offshore Mechanics and Arctic Engineering. 137(4). doi:10.1115/1.4030255
[22] Moe-Fore, H., Lader, P., Lien, E., and Hopperstad, O. (2016). Structural response of high solidity net cage models in uniform flow, Journal of Fluids and Structures. 65:180--195. doi:10.1016/j.jfluidstructs.2016.05.013
[23] Priour, D. (1999). Calculation of net shapes by the finite element method with triangular elements, Communications in Numerical Methods in Engineering. 15(10):755--763. doi:10.1002/(SICI)1099-0887(199910)15:10<755::AID-CNM299>3.0.CO;2-M
[24] Su, B., Kelasidi, E., Frank, K., Haugen, J., Fore, M., and Pedersen, M.O. (2021). An integrated approach for monitoring structural deformation of aquaculture net cages, Ocean Engineering. 219:108424. doi:10.1016/j.oceaneng.2020.108424
[25] Tsukrov, I., Eroshkin, O., Fredriksson, D., Swift, M.R., and Celikkol, B. (2003). Finite element modeling of net panels using a consistent net element, Ocean Engineering. 30(2):251--270. doi:10.1016/S0029-8018(02)00021-5
[26] Tsukrov, I.I., Ozbay, M., Swift, M.R., Celikkol, B., Fredriksson, D.W., and Baldwin, K. (2000). Open ocean aquaculture engineering: numerical modeling, Marine Technology Society Journal. 34(1):29--40. doi:10.4031/MTSJ.34.1.4
[27] Turnbull, J., Bell, A., Adams, C., Bron, J., and Huntingford, F. (2005). Stocking density and welfare of cage farmed atlantic salmon: application of a multivariate analysis, Aquaculture. 243(1-4):121--132. doi:10.1016/j.aquaculture.2004.09.022
[28] Zhan, J., Jia, X., Li, Y.S., Sun, M., Guo, G., and Hu, Y. (2006). Analytical and experimental investigation of drag on nets of fish cages, Aquacultural engineering. 35(1):91--101. doi:10.1016/j.aquaeng.2005.08.013
[29] 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. doi:10.1016/j.oceaneng.2015.09.043

  title={{An Integrated Approach to Modelling Fish Cage Response in the Flow}},
  author={Gao, Sihan and Gansel, Lars Christian and Li, Guoyuan and Zhang, Houxiang},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}