Numerical simulation of the hydrodynamics within octagonal tanks in recirculating aquaculture systems

作     者：柳瑶 刘宝良 雷霁霖 关长涛 黄滨 

作者机构：Key Laboratory for Sustainable Development of Marine FisheriesMinistry of AgricultureYellow Sea Fisheries Research InstituteChinese Academy of Fishery Sciences Shandong UnivercityWeihaiMarine College 

出 版 物：《Chinese Journal of Oceanology and Limnology》 (中国海洋湖沼学报（英文版）)

年 卷 期：2017年第35卷第4期

页      面：912-920页

核心收录：

学科分类：090801[农学-水产养殖] 0908[农学-水产] 09[农学] 

基　　金：Supported by the Application Research Project of Post-Doctoral Researchers in Qingdao(No.ZQ51201415037) the Modern Agriculture Industry System Construction of Special Funds(No.CARS-50-G10) the Special Project about Independent Innovation and Achievement Transformation of Shandong Province(No.2014ZZCX07102) the Key R&D Program of Jiangsu Province(No.BE2015328) 

主　　题：recirculating aquaculture systems octagonal tanks hydrodynamic simulation rate of particle removal 

摘      要：A three-dimensional numerical model was established to simulate the hydrodynamics within an octagonal tank of a recirculating aquaculture system. The realizable k-e turbulence model was applied to describe the flow, the discrete phase model （DPM） was applied to generate particle trajectories, and the governing equations are solved using the finite volume method. To validate this model, the numerical results were compared with data obtained from a full-scale physical model. The results show that： （1） the realizable k-e model applied for turbulence modeling describes well the flow pattern in octagonal tanks, giving an average relative error of velocities between simulated and measured values of 18% from contour maps of velocity magnitudes; （2） the DPM was applied to obtain particle trajectories and to simulate the rate of particle removal from the tank. The average relative error of the removal rates between simulated and measured values was 11%. The DPM can be used to assess the self-cleaning capability of an octagonal tank; （3） a comprehensive account of the hydrodynamics within an octagonal tank can be assessed from simulations. The velocity distribution was uniform with an average velocity of 15 cm/s; the velocity reached 0.8 m/s near the inlet pipe, which can result in energy losses and cause wall abrasion; the velocity in tank corners was more than 15 cm/s, which suggests good water mixing, and there was no particle sedimentation. The percentage of particle removal for octagonal tanks was 90% with the exception of a little accumulation of 〈5 mm particle in the area between the inlet pipe and the wall. This study demonstrated a consistent numerical model of the hydrodynamics within octagonal tanks that can be further used in their design and optimization as well as promote the wide use of computational fluid dynamics in aquaculture engineering.