不同植物穿孔板结构的水输运特性分析  

Analysis of water transport characteristics in plant with different perforation plate structures

作　　者：伍根生 苏桐 谢建军 陈伟宇 袁志山[2] WU Gensheng;SU Tong;XIE Jianjun;CHEN Weiyu;YUAN Zhishan(College of Mechatronics Engineering,Nanjing Forestry University,Nanjing,Jiangsu 210037,China;College of Electromechanical Engineering,Guangdong University of Technology,Guangzhou,Guangdong 510006,China)

机构地区：[1]南京林业大学机械电子工程学院,江苏南京210037 [2]广东工业大学机电工程学院,广东广州510006

出　　处：《排灌机械工程学报》2025年第1期80-86,共7页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51905276);江苏省自然科学基金资助项目(BK20200787)。

摘　　要：为揭示木质部穿孔板几何分布及结构参数对导管水输运的影响,采用计算流体动力学方法构建了植物微结构流体模型,并结合伯努利方程,基于低雷诺数k-ε湍流物理场,研究3种穿孔板结构内部微流动机理.通过压力差、流动阻力系数及水力传导率的变化分析导管内径、穿孔板种类、倾斜角、孔数及等效直径比对导管水输运的影响规律.结果表明:相较内径40μm,穿孔板倾斜角20°、等效直径比0.84的单穿孔板导管,网状穿孔板导管压力差增大了44.2%,流动阻力系数增大了53.3%;梯状穿孔板导管压力差增大了76.5%,流动阻力系数增大了92.3%.相同参数下,导管压力差及流动阻力系数与导管内径、穿孔板倾斜角及等效直径比成反比,与穿孔板孔数成正比.其中,单穿孔板倾斜角对导管水输运特性影响较小.3种导管水力传导率按孔板排序从大到小依次为单穿孔板、网状穿孔板和梯状穿孔板.内径越大的导管水力传导率越高.The aim of this work is to reveal the effect of the geometric distribution and structural parameters of xylem perforation plates on vessel hydraulic characteristics.By the computational fluid dynamics(CFD)method,the micro-flow mechanism in the vessels with three perforation plates was si-mulated by a k-εturbulent physical field with a low Reynolds number combined with the Bernoulli equation.The impacts of the inner diameter,the type of perforation plates,as well as their inclination angle,hole number,and equivalent diameter ratio on water transport in the vessel were examined in terms of the pressure difference,the flow resistance coefficient,and the hydraulic conductivity.By comparing with a simple perforation plate,the pressure drop of the vessel with a reticulate perforation plate increases by 44.2%,and the flow resistance coefficient increases by 53.3%.The pressure drop of the vessel with a scalariform perforation plate increases by 76.5%,and the flow resistance coefficient increases by 92.3%.As other parameters are consistent,the pressure difference and the vessel flow resistance are inversely proportional to the vessel inner diameter,the inclination angle of perforation plates,and the equivalent diameter ratio.Meanwhile,the two parameters are proportional to the hole number.Furthermore,the effect of water transfer on the inclination angle of a simple perforation plate is negligible.The hydraulic conductivity of the three vessels is ordered from high to low as follows:simple perforation plate,reticulate perforation plate,and scalariform perforation plate.The larger the inner diameter of a vessel,the higher the hydraulic conductivity.

关 键 词：水输运 木质部穿孔板 伯努利方程 低雷诺数k-ε湍流模型 流动阻力系数 

分 类 号：S277.9[农业科学—农业水土工程]