压力补偿灌水器流固耦合计算方法  

Fluid-structure interaction analysis method for pressure compensating emitter

作　　者：周兴[1] 魏正英[1] 苑伟静[1] 王立朋[1] 

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

出　　处：《农业工程学报》2013年第2期30-36,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家"十二五"农村领域国家科技计划资助项目"低能耗灌水器开发"(2011AA100507)

摘　　要：为提高压力补偿灌水器的设计精度与设计效率,研究了压力补偿灌水器流固耦合数值计算方法,并采用快速成型技术制作的灌水器试验件进行水力性能试验,从流量的角度对压力补偿灌水器流固耦合计算方法进行验证。结果表明,采用SSTK-ω紊流模型进行流场计算、自适应网格重划分方法对变形的流体网格进行重构、结合弹性膜片的接触分析的流固耦合计算方法所得到的灌水器流量结果与试验结果最大偏差为2.5%,能够对压力补偿灌水器一定工作压力范围内的流量进行准确预测,可为压力补偿灌水器快速开发提供理论依据、减少试验次数、缩短开发周期、提高设计精度。Pressure compensating emitter （PCE） can maintain a constant flow rate over a wide range of working pressures, and has extensive application prospect in mountain regions where there are often great changes of hydraulic pressure in conduit pipe. The rapid design method for non-pressure-compensating emitter based on CFD is a quite mature technology at present. However, as there is two-way coupled interaction between fluid flow and elastic diaphragm in the PCE, the common CFD method is not suitable for the flow rate prediction in the design of PCE. In order to improve the design accuracy and efficiency of PCE, the fluid-structure interaction （FSI） analysis method was studied in this paper. In addition, hydraulic performance tests were carried out to verify the FSI analysis results with the test samples by rapid prototyping and manufacturing （RP＆M）. There are two major difficulties in the FSI analysis of PCE： 1） Distortion of the fluid mesh in a confined space caused by the deformation of diaphragm may lead to termination of the analysis; 2） It is difficult to obtain the convergent result because of the nonlinearity including the material nonlinearity of the rubber diaphragm, the geometric nonlinearity of the diaphragm’s large deformation and the state nonlinearity of the contact between diaphragm and emitter’s main body. And moreover, the coupled fluid-structure equation is a nonlinear system. Thus an adaptive mesh repair technique was adopted to refine the distorted fluid mesh and incremental method and displacement-pressure finite element formulation was used for the nonlinear analysis of the incompressible material. In this paper, SST K-ω turbulence model was used for the fluid analysis, contact analysis method and Neo-Hookean Mooney-Rivlin rubber material model was adopted for the structure analysis. The working process of PCE can be obtained through the FSI analysis result. The results shows that when the distance between the diaphragm and the outlet of pressure-compensating （PC） cha

关 键 词：灌溉 计算流体力学 压力 灌水器 流固耦合 自适应网格重划 SSTK-ω紊流模型 接触分析 

分 类 号：S275.6[农业科学—农业水土工程]