Cable tension formulas for gravity net cage arrays in current

Abstract

Due to the structural complexity and size, many gravity net cage array prototypes are modeled, simulated, and analyzed to select the potential mooring system. However, the complexity of these systems requires a significant amount of time to configure and compute the mooring dynamics in the preliminary design stage. Because the net cage array reaches an equilibrium state in a specific current condition, the cable tension is static and predictable for a given mooring system configuration. Therefore, based on a quasi-static method, load formulas that resolve cable tension are derived to reflect relationships among the cable tension, net cage array size, mooring system configuration, and current conditions. Compared to the tension obtained from numerical simulations, the cable tension predicted by the formulas has a 67% probability of error within ±5%, and a 96% probability of error within ±10%, respectively. Additionally, the formula characteristics also provide valuable information for the mooring system design. The mooring system of a 2 × 4 net cage array is designed according to the derived cable tension formulas. This research provides an efficient and rapid method for preliminary design and sizing components for a mooring system of gravity net cage array.