Comparison on the forces and deformation between HDPE cylinder netcage and truncatedcone netcage in current
CSTR:
Author:
Affiliation:

Clc Number:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
  • |
  • Comments
    Abstract:

    Deep-water net-cages made from HDPE,are the most widely used aquaculture facility among all kinds of anti-wave net-cages.They can be divided into cylinder netcage and truncated-cone net-cage according to different net shapes.Comparing and analyzing the similarities and differences in the aspects of the forces and deformation between cylinder net-cage and truncated-cone net-cage,could help to provide a strong reference for the selection of cage style.Using lumped mass method and the rigid body kinematics principle,this paper described a numerical model including floating circular model as well as net model for simulating the force and deformation of net-cages in current,and the accuracy of simulation was validated by the data of marine in-situ measurements.By comparing,the numerical results of the mooring line forces on the cage were in good agreement with the in-situ test data,only 7% of maximum relative error and 4.6% of average relative error between them.The results indicated the numerical model and computational method adopted could meet the need of calculation accuracy for practical study.On the basis of that,under the conditions of two weight sizes(GW1=350 kg,GW2=600 kg)and five kinds of current velocities(U=0.3-0.9 m/s),the drag forces and the volume reduction rate for cylinder net-cage and truncated-cone net-cage were calculated.In the process of simulating net,the mesh grouping method that 28?28 meshes have been combined into an equivalent large mesh,was applied to decrease computational time and improve efficiency.The results showed that after cages getting equilibrium in current,the two different cages in both drag force and cage volume kept the similar varying tendency with weight size or current velocity,only had little difference between them.The volume reduction rate of cylinder net-cage was much greater than that of truncated-cone net-cage.The cylinder net-cage had an obvious initial deformation when cage was only impacted by sinkers,the volume reduction rate of which was about 28% in relatively small velocity U=0.3 m/s,but the truncated-cone net-cage had better anti-current and anti-deformation performances,with about 5% of volume reduction rate.Therefore,to decrease the loss of net volume in current as well as manufacturing cost,selecting truncated-cone net-cages with sinkers weight mode has more advantages than cylinder net-cages with that for aquaculture.

    Reference
    Related
    Cited by
Get Citation

HUANG Xiao-hua, GUO Gen-xi, HU Yu, TAO Qi-you, ZHANG Xiao-ming. Comparison on the forces and deformation between HDPE cylinder netcage and truncatedcone netcage in current[J]. Journal of Fisheries of China,2011,35(1):124~130

Copy
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:September 28,2010
  • Revised:November 09,2010
  • Adopted:December 01,2010
  • Online: January 14,2011
  • Published: January 15,2011
Article QR Code