Development of the design an‎d size of marine single point mooring cage for small scale mariculture in costal areas of south of Iran ( Ban‎dar Lenge)

10/19/2026 12:00:00 AM

Fish farming in cages, as a key strategy for providing sustainable protein, faces challenges related to localization in the southern coasts of Iran. Large-scale imported models are not compatible with the economic capacity of small-scale fish farmers in areas such as Ban‎dar Lengeh, highlighting the need for the development of indigenous, cost-effective designs tailored to the regionʹs hydrodynamic conditions. This research was conducted with the primary objective of designing an‎d eva‎luating the performance of an indigenous floating fish cage model with a single-point mooring system (SPM) for local farmers. To achieve this goal, an indigenous model of a floating fish cage with a single-point mooring system was proposed. This system includes a cage with a diameter of 10 meters an‎d three mooring lines, each 136 meters long, made of a combination of chains an‎d polyester. These three mooring lines are connected to a buoy, which is linked to the cage via a 12-meter mooring line. The performance of this system was assessed using the OrcaFlex software, an‎d it appears to demonstrate satisfactory performance. The maximum volume reduction of the cage was 15.84%, which falls within an acceptable range, an‎d the stress levels in the components were below the yield stress of the respective materials. For instance, the maximum stress recorded on the floating ring was between 25 an‎d 30 megapascals, which is less than the yield stress of polyethylene (30 megapascals). The displacement of the components was also within expected limits; for example, the vertical displacement of the floating ring was less than 0.5 meters, which is considered acceptable when compared to real-world conditions. However, it seems that a better design for the structure is recommended to address the required safety factors. Given that the current design covers the stress range from the 10th to the 90th percentile (90% quantile), the structure may face challenges under conditions of maximum applied stress.

قفس پرورش ماهي , سيستم تك مهار , مدل‌سازي عددي , نرم‌افزار اوركافلكس , تحليل هيدروديناميكي

Fish cage aquaculture , single-point mooring system , numerical modeling , OrcaFlex software , hydrodynamic analysis

Seyed Erfan Mousavi Anzahaei

Dr. Seyed Mostafa Siadatmousavi - Dr. Zohreh Sadat Haghayeghi