基于模型试验准则的重力式圆形网箱水动力比较研究
|
摘要
模型试验准则是水槽模型试验的核心问题,关系到最终推算实物系统结果的准确性。以中国常用的高密度聚乙烯(HDPE)圆形重力式网箱为研究对象,采用田内准则和狄克逊准则为模型试验准则,以大尺度比10∶1、小尺度比2∶1设计制作了网箱模型,在循环动力水槽中分别进行网箱水动力特性模型试验,比较在水流作用下两种准则的试验结果及其差异性。结果显示:网箱整体和网箱箱体的阻力随着流速增加而增加,二者呈幂函数关系;网箱整体阻力系数(C)随着雷诺数(Re)的增加而减小,二者的关系为C=17.587Re~(-0.354)(R~2=0.941);C随着Re的增加而减小,二者的关系为C=30.526 Re~(-0.424)(R~2=0.902);在实际流速30~130 cm/s范围内,田内准则的试验数据比狄克逊准则的试验数据稍小,二者的阻力差约为-5%。由试验结果可知,田内准则和狄克逊准则均可用于网箱模型水流试验。研究结果可为网箱模型实验准则的选择和圆形网箱水动力学计算提供理论依据和基本参数。
Model experiment criterion is the core of flume model experiments,which will directly influenced the accuracy of the final results. In this paper,we made a research on a widely used circular HDPE sea cage system in China. We designed and made the cage model under the Tauti Criterion and Dickson Criterion( the large scale is 10,and the small scale is 2). The hydrodynamic model experiments are conducted in a circulation water channel,so as to compare the different results under the two criteria. The studies showed that drag of the whole cage and cage net increases as the velocity increases,and there is a power function relationship between them; the whole cage 's drag coefficient decreases as the Reynolds number( Re)increases,which can be expressed as C = 17. 587 Re~(-0. 354)( R~2= 0. 941); the relationship between net's drag coefficient and Reynolds number is same to the whole cage's,C = 30. 526 Re~(-0. 424)( R~2= 0. 902); When the actual velocity is 30-130 cm/s,the experiment results under Tauti Criterion are always about 5% smaller than that under Dickson Criterion. The results showed both the two criteria can be exactly used in the cage model experiment. This paper provided theoretical basis and basic parameters to circular cage's hydrodynamic calculation.
Model experiment criterion is the core of flume model experiments,which will directly influenced the accuracy of the final results. In this paper,we made a research on a widely used circular HDPE sea cage system in China. We designed and made the cage model under the Tauti Criterion and Dickson Criterion( the large scale is 10,and the small scale is 2). The hydrodynamic model experiments are conducted in a circulation water channel,so as to compare the different results under the two criteria. The studies showed that drag of the whole cage and cage net increases as the velocity increases,and there is a power function relationship between them; the whole cage 's drag coefficient decreases as the Reynolds number( Re)increases,which can be expressed as C = 17. 587 Re~(-0. 354)( R~2= 0. 941); the relationship between net's drag coefficient and Reynolds number is same to the whole cage's,C = 30. 526 Re~(-0. 424)( R~2= 0. 902); When the actual velocity is 30-130 cm/s,the experiment results under Tauti Criterion are always about 5% smaller than that under Dickson Criterion. The results showed both the two criteria can be exactly used in the cage model experiment. This paper provided theoretical basis and basic parameters to circular cage's hydrodynamic calculation.
引文
[1]关长涛,林德芳,黄滨,等.深海抗风浪网箱养殖设施与装备技术的研究进展[J].现代渔业信息,2007,22(4):3-8.
[2]徐皓,江涛.我国离岸养殖工程发展策略[J].渔业现代化,2012,39(4):1-7.
[3]王鲁民,黄洪亮,王明彦.圆形重力式网箱阻力性能研究[J].中国海洋大学学报,2004,34(4):554-559.
[4]TSUKROV I,OZBAY M,SWIFT M R,et al.Open ocean aquaculture engineering numerical modeling[J].Marine Technology Society Journal,2000,34(1):29-40.
[5]朱立新,梁振林,赵芬芳,等.网箱的概念简化与力学计算[J].中国水产科学,2004,11(Sl):19-25.
[6]黄六一,梁振林,赵芬芳,等.网箱形状在海流中变化的模型实验[J].青岛海洋大学学报,2006,36(2):244-248.
[7]HUANG CC,TANG H J,LIU J Y,et al.Modeling volume deformation in gravity-type cages with distributed bottom weights or a rigid tub e-sinker[J].Aquacultural Engineering,2007,37:144-157.
[8]FREDRIKSSON D W,DECEW J C,TSUKROV I,et al.Development of structural modeling techniques for evaluating HDPE plastic net pens used in marine aquaculture[J].Ocean Engineering,2007,34:2124-2137.
[9]ZHAO Y P,LI Y C,DONG G H,et al.Numerical simulation of the effects of structure size ratio and mesh type on threedimensional deformation of the fishing-net gravity cage in current[J].Aquacultural Engineering,2007,36:284-301.
[10]LADER P,DEMPSTER T,FREDHEIM A,et al.Current induced net deformations in full-scale sea-cages for Atlantic salmon[J].Aquacultural Engineering,2008,38:52-65.
[11]崔勇,关长涛,万荣,等.基于有限元方法对波流场中养殖网箱的系统动力分析[J].工程力学,2008,27(5):250-256.
[12]黄六一,梁振林,万荣,等.波流作用下网格锚泊的单个重力式网箱缆绳张力[J].中国水产科学,2011,18(3):636-645.
[13]黄六一,梁振林,宋伟华,等.方形箱网结构减流效果实验[J].中国水产科学,2007,14(5):860-863.
[14]林德芳,关长涛,黄文强,等.抗风浪网箱材料性能的研究[J].海洋水产研究,2004,25(5):57-60.
[15]袁春海.乙丙无规共聚PPR管材料B4101性能分析及生产工艺优化[J].中外能源,2009,14(7):83-89.
[16]周应祺,许柳雄,何其渝.渔具力学[M].北京:中国农业出版社,2001:119-133.
[17]陈雪忠,黄锡昌.渔具模型试验理论与方法[M].上海:上海科技出版社,2011:19-154.
[18]ZHAO Y P,BI C W,DONG G H,et al.Numerical simulation of the flow field inside and around gravity cages[J].Aquacultural Engineering,2013,52:1-13.
[19]MIYAZAKI Y.Basic investigations on the resistance of fishing net-(Ⅳ)The resistance of ropes placed obliquely to the stream[J].Journal of Tokyo University of fisheries,1964,50:111-123.
[20]HUANG L Y,ZHANG L,DONG T W,et al.Experimental study on hydrodynamic characteristics of three stranded polyethylene rope[J].Applied mechanics and material,2014,490-491(4):421-429.
[2]徐皓,江涛.我国离岸养殖工程发展策略[J].渔业现代化,2012,39(4):1-7.
[3]王鲁民,黄洪亮,王明彦.圆形重力式网箱阻力性能研究[J].中国海洋大学学报,2004,34(4):554-559.
[4]TSUKROV I,OZBAY M,SWIFT M R,et al.Open ocean aquaculture engineering numerical modeling[J].Marine Technology Society Journal,2000,34(1):29-40.
[5]朱立新,梁振林,赵芬芳,等.网箱的概念简化与力学计算[J].中国水产科学,2004,11(Sl):19-25.
[6]黄六一,梁振林,赵芬芳,等.网箱形状在海流中变化的模型实验[J].青岛海洋大学学报,2006,36(2):244-248.
[7]HUANG CC,TANG H J,LIU J Y,et al.Modeling volume deformation in gravity-type cages with distributed bottom weights or a rigid tub e-sinker[J].Aquacultural Engineering,2007,37:144-157.
[8]FREDRIKSSON D W,DECEW J C,TSUKROV I,et al.Development of structural modeling techniques for evaluating HDPE plastic net pens used in marine aquaculture[J].Ocean Engineering,2007,34:2124-2137.
[9]ZHAO Y P,LI Y C,DONG G H,et al.Numerical simulation of the effects of structure size ratio and mesh type on threedimensional deformation of the fishing-net gravity cage in current[J].Aquacultural Engineering,2007,36:284-301.
[10]LADER P,DEMPSTER T,FREDHEIM A,et al.Current induced net deformations in full-scale sea-cages for Atlantic salmon[J].Aquacultural Engineering,2008,38:52-65.
[11]崔勇,关长涛,万荣,等.基于有限元方法对波流场中养殖网箱的系统动力分析[J].工程力学,2008,27(5):250-256.
[12]黄六一,梁振林,万荣,等.波流作用下网格锚泊的单个重力式网箱缆绳张力[J].中国水产科学,2011,18(3):636-645.
[13]黄六一,梁振林,宋伟华,等.方形箱网结构减流效果实验[J].中国水产科学,2007,14(5):860-863.
[14]林德芳,关长涛,黄文强,等.抗风浪网箱材料性能的研究[J].海洋水产研究,2004,25(5):57-60.
[15]袁春海.乙丙无规共聚PPR管材料B4101性能分析及生产工艺优化[J].中外能源,2009,14(7):83-89.
[16]周应祺,许柳雄,何其渝.渔具力学[M].北京:中国农业出版社,2001:119-133.
[17]陈雪忠,黄锡昌.渔具模型试验理论与方法[M].上海:上海科技出版社,2011:19-154.
[18]ZHAO Y P,BI C W,DONG G H,et al.Numerical simulation of the flow field inside and around gravity cages[J].Aquacultural Engineering,2013,52:1-13.
[19]MIYAZAKI Y.Basic investigations on the resistance of fishing net-(Ⅳ)The resistance of ropes placed obliquely to the stream[J].Journal of Tokyo University of fisheries,1964,50:111-123.
[20]HUANG L Y,ZHANG L,DONG T W,et al.Experimental study on hydrodynamic characteristics of three stranded polyethylene rope[J].Applied mechanics and material,2014,490-491(4):421-429.