摘要
为解决水系统中分水器的主要综合性能问题,采用计算流体力学理论,对分水器按实际尺寸进行了二维数值计算,研究了分水器压强小于1.25MPa,入口水流Re小于4.73×104的正常工作情况下分水器内部速度、压力、水头损失率随人口Re变化规律。计算结果表明:分水器中的速度分布在第一个分路口前不是标准的"抛物线形状";在每个分路口后速度逐级降低,降低规律明显;最后分路口后有漩涡区。分水器入口Re为2.37×104时,分路口入口右侧靠近壁面受水流冲击产生剪切应力较小。不同入口Re的分水器内动压分布相似,动压大小与分水器入口Re有关。不同入口Re的分水器分路出口水头损失曲线相似,分路1水头损失率最大,分路4为最小值;在分水器中流道形式、壁面糙度一定的情况下,减小局部阻力损失较好的方法就是降低入口Re。计算结果为分水器制造和为供水系统的阻力计算提供了基础数据。
In order to solve the major comprehensive performance issues about manifolds in water system, this paper used computational fluid dynamics theory to make two-dimensional numerical simulation for the actual size of manifolds,studied the variation of velocity,pressure,head loss with the Re of inlet in man-ifolds when the pressure in manifolds was less than 1.25MPa and Re of inlet flow was less than 4.73×104.The results showed that the velocity distribution in manifolds before the first intersection was not a standard ＂parabolic shape＂,and velocity reduced successively in each junction and there was a vortex after the last junction.When Re in entrance of manifold was 2.37×104,the right inlet had less shear stress with flowing.Different Re in entrance of manifold had similar dynamic pressure and head loss curve,and the dynamic pressure had connection with the Re of manifold inlet.The first by-pa tube had the largest rate,the forth by-pa tube had the minimum rate; In the certain mid-stream water separator road forms and wall roughness condition,the better way to reduce the local resistance was to reduce the Re of entrance.The results provided the basic data for manifolds manufacturing and resistance calculation of water supply systems.
出处
《水资源与水工程学报》
2010年第4期89-91,95,共4页
Journal of Water Resources and Water Engineering
基金
辽宁工程技术大学研究生科研立项资助(Y201001203)
关键词
分水器
局部阻力系数
速度变化
计算流体力学
变化规律
数据结论
manifold
coefficient of local resistance
velocity change
computational fluid dynamics （CFD）
variation rule
data conclusions
