滴头锯齿型迷宫流道消能特性的流体动力学分析  

Hydrokinetics Analysis on the Pressure Losses in Sawtooth-labyrinth Path Drip Irrigation Emitters

作　　者：李云开[1] 刘世荣[2] 杨培岭[1] 任树梅[1] 林雄财[1] 

机构地区：[1]中国农业大学水利与土木工程学院 [2]中国农业大学烟台研究院

出　　处：《农业机械学报》2007年第12期49-52,共4页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(项目编号:50609029;50379053);国家"863"高新技术研究发展计划资助项目(项目编号:2002AA6Z3091);中国农业大学科研启动基金资助项目(项目编号:2005065)

摘　　要：在对所选取的3种代表性锯齿型迷宫式滴头流道参数进行精确测定的基础上,利用圆管紊流理论和CFD流场模拟软件对锯齿形迷宫流道的消能机理进行了研究。结果表明:光滑圆管紊流理论不足以解释锯齿型迷宫流道的消能机理;压力沿流道长度方向呈线性递减,各消能尖角单元压力损失相等,符合线性叠加规律;摩阻系数随着压力增加而降低,并很快稳定在一定数值上;在中、高压区滴头流道内部流动为紊流,在低压区可能存在从层流到紊流或者光滑紊流到全紊流的流态转捩行为。Labyrinth path drip irrigation emitter is one of the predominant drippers. Based on the exact test to the geometry parameters of three representative sawtooth-labyrinth paths, the mechanism of pressure losses in the flow path was studied by the smooth pipe turbulence theory and CFD （computational fluid dynamics）technology of flow regime. The mechanism of pressure losses in sawtooth-labyrinth path couldn＇t be explained with smooth pipe turbulence theory. The pressure was descending with linearity rules along the flow path, and the head losses was equaled. The friction coefficient reduced with the pressure increasing, and it was stabilized to a value soon. The flow regime is turbulent within the sawtooth-labyrinth paths the pressure zone higher than 50 kPa, and it is possible that the transformation behaviors of the flow from laminar flow or smooth turbulent into turbulent flow were existed.

关 键 词：滴头 迷宫式流道 压力损失 消能机理 摩阻系数 

分 类 号：S275.6[农业科学—农业水土工程] O351.2[农业科学—农业工程]