滴头壁面形貌对微颗粒与壁面黏附特性的影响  

Influence of Emitter's Channel Wall Topography on Particle-Wall Adhesion

作　　者：曹蒙[1] 魏正英[1] 葛令行[1] 唐一平[1] 卢秉恒[1] 

机构地区：[1]西安交通大学机械制造系统工程国家重点实验室,西安710049

出　　处：《西安交通大学学报》2009年第9期120-124,共5页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50675172);国家"863规划"资助项目(2006AA100214-5);全国博士学位论文作者专项资金资助项目(200740)

摘　　要：为了研究在含沙滴灌条件下,灌水器迷宫流道内壁面形貌对灌水器内流动特性以及流道内颗粒-壁面黏附的影响,以详细分析灌水器的堵塞机理,对不同形貌的矩形流道进行了水力性能测试实验,并利用粒子图像测速(PIV)平台对灌水器流道内颗粒-壁面黏附进行可视化实验,结合计算流体动力学的方法对其流场进行了数值仿真计算.研究结果表明:壁面粗糙元(高度为流道水力直径的10%)使得流道的阻力系数显著增大,即在同一工作压力下灌水器的出口流量变小;粗糙元改变了流道内沙粒浓度的分布,且粗糙元附近的沙粒速度较低,粒子与壁面碰撞后更容易黏附壁面,使得灌水器流道更容易堵塞.Aiming at the influence of labyrinth channel wall topography on the flow behavior and adhesion between particles and channel wall under the condition of silt-content irrigation, the emitter channels of different wall topography are chosen, and the hydraulic performance tests and the visual experiments on particle-wall adhesion are conducted via particle image velocimetry （PIV）. The computational fluid dynamics is utilized to numerically simulate the flow field. The results show that the higher the wall roughness（the value is 10% of the hydraulic diameter）, the greater the resistance coefficient will be. That is, under the same pressure, the smaller the outlet flow rate, the more easily the particle-wall adhesion occurs. Wall roughness affects particle concentration distribution, and the particle velocity near the roughness elements is low, resulting in emitter clogging.

关 键 词：灌水器 迷宫流道 粗糙元 黏附 

分 类 号：S275.6[农业科学—农业水土工程]