Study on the influence of different weight systems on hydrodynamic characteristics of hdpe circular gravity fish cage
The preservation of volume within gravity cages,particularly in the face of strong water currents,is intricately linked to the health and growth of farmed fish.Moreover,the distinct weight systems employed in these cages play a pivotal role in shaping both their volume retention rate and resistance against external hydrodynamic forces.To delve into the impact of various weight systems on the hydrodynamic features of net cages,this study employs the Tauti criterion.Model experiments are conducted on a 40-meter circumference HDPE gravity-based net cage,exploring four distinct weight systems.The investigation meticulously examines the interconnections among force distribution,volume retention,and current velocity to provide a comprehensive understanding of the hydrodynamic dynamics at play.The results underscore a consistent trend:irrespective of the weight type,the cage's resistance systematically escalates with increasing velocity and total weight.This escalation follows a discernible power function relationship between force and current velocity.Intriguingly,cages utilizing chains demonstrate minimal changes in resistance as total weight gradually increases,presenting a noteworthy contrast to their counterparts using weighted weights.At a specific velocity,a strategic amalgamation of a"bottom frame,reinforced ring,and weighted weights"emerges as the optimal configuration,achieving the pinnacle of volume retention for the cage.Delving further into specific conditions,under a peak experimental current velocity of 70.7 cm/s and varying total weight scenarios,the effective volume is consistently maintained at 65.96%,69.10%,and 71.72%,respectively.Furthermore,the cage employing this specific weight system not only attains maximum volume retention but also displays optimal performance by minimizing force per unit volume at designated current velocities and total weights.Through meticulous dimensionless treatment,a substantial negative correlation between cage resistance and effective volume is unveiled,leading to the proposal of a novel quantitative analysis method.In summary,these findings not only elucidate the nuanced dynamics of cage resistance but also offer practical insights into optimizing weight systems for enhanced volume retention in HDPE gravity net cages.These research results provide useful reference for the design and application of the weight system of HDPE gravity net cages.
gravity net cageweight systemmodel testhydrodynamic characteristicsvolume loss