TY - JOUR

T1 - Hydrodynamic coefficients of mussel dropper lines derived from large-scale experiments and structural dynamics

AU - Landmann, Jannis

AU - Flack, Christian

AU - Kowalsky, Ursula

AU - Wüchner, Roland

AU - Hildebrandt, Arndt

AU - Goseberg, Nils

N1 - Funding Information: This research was partially supported with funding from the New Zealand Ministry of Business, Innovation and Employment through the Cawthron Institute project CAWX1607. Furthermore, the authors gratefully thank Dirk and Daniela Haase from Meerwasseraquaristik Haase, Hannover, Germany for providing cooling and aeration equipment for the mussel storage.

PY - 2024/2

Y1 - 2024/2

N2 - The expansion of marine aquaculture production is driven by a high market demand for marine proteins and a stagnation of wild catch of fish. Bivalve farming, i.e., the cultivation of oysters, mussels and scallops, is an important part of the ongoing market dynamics and production expansion. As marine spatial planning is considering various use purposes, available space for near-shore aquaculture is already becoming scarce; this has fueled research and development initiatives to enable production installations further offshore. The highly energetic conditions at more exposed offshore marine sites lead to increased loads on aquaculture systems and their components and it is still not sufficiently understood how the load transfer from oceanic environmental conditions onto shellfish-encrusted surfaces attached to elastic ropes may be appropriately quantified. This study data gathered large-scale data sets in a wave tank facility, which are used to validate a novel, numerical model, building on the dynamics of rope structures which allows for the determination of the hydrodynamic loads transferred to the dropper lines. The forces and hydrodynamic parameters are measured and numerically analyzed. Based on the results, drag and inertia coefficients are determined. A drag coefficient of CD= 1.1 and an inertia coefficient of CM= 1.7 are recommended to model shellfish-encrusted dropper lines exposed to oscillatory flows with KC = 40–90. The numerical model for the determination of wave-induced forces on mussel dropper lines is developed and validated using the experimental data. It employs a modified Morison equation, which takes into account the displacement of the mussel dropper line. The influence of varying aquaculture-related parameters is discussed by applying the numerical model. Based on the gathered insights, recommendations can be given from an engineering point of view concerning the optimal placement of mussel aquaculture within the water column.

AB - The expansion of marine aquaculture production is driven by a high market demand for marine proteins and a stagnation of wild catch of fish. Bivalve farming, i.e., the cultivation of oysters, mussels and scallops, is an important part of the ongoing market dynamics and production expansion. As marine spatial planning is considering various use purposes, available space for near-shore aquaculture is already becoming scarce; this has fueled research and development initiatives to enable production installations further offshore. The highly energetic conditions at more exposed offshore marine sites lead to increased loads on aquaculture systems and their components and it is still not sufficiently understood how the load transfer from oceanic environmental conditions onto shellfish-encrusted surfaces attached to elastic ropes may be appropriately quantified. This study data gathered large-scale data sets in a wave tank facility, which are used to validate a novel, numerical model, building on the dynamics of rope structures which allows for the determination of the hydrodynamic loads transferred to the dropper lines. The forces and hydrodynamic parameters are measured and numerically analyzed. Based on the results, drag and inertia coefficients are determined. A drag coefficient of CD= 1.1 and an inertia coefficient of CM= 1.7 are recommended to model shellfish-encrusted dropper lines exposed to oscillatory flows with KC = 40–90. The numerical model for the determination of wave-induced forces on mussel dropper lines is developed and validated using the experimental data. It employs a modified Morison equation, which takes into account the displacement of the mussel dropper line. The influence of varying aquaculture-related parameters is discussed by applying the numerical model. Based on the gathered insights, recommendations can be given from an engineering point of view concerning the optimal placement of mussel aquaculture within the water column.

KW - Aquaculture engineering

KW - Bivalves

KW - Drag

KW - Hydrodynamic coefficients

KW - Inertia

KW - Mussels

KW - Offshore

UR - http://www.scopus.com/inward/record.url?scp=85177782739&partnerID=8YFLogxK

U2 - 10.1007/s40722-023-00306-w

DO - 10.1007/s40722-023-00306-w

M3 - Article

AN - SCOPUS:85177782739

VL - 10

SP - 175

EP - 192

JO - Journal of Ocean Engineering and Marine Energy

JF - Journal of Ocean Engineering and Marine Energy

SN - 2198-6444

ER -