But now it ' s urgent to adopt new methods for calculating the head loss of regional drainage due to some factors such as long length , large flow quantity and probable strong topographic change 由于存在管线长、流量大以及区域地形变化幅度可能较大等因素，建设区域排水系统需要采用新的方法较为准确地计算水头损失。
The open angle , head loss and hydrodynamic pressure under the rated flow and several kinds of proportion are carefully observed in the model test , and these results are given for reference in engineering design 阶段模型试验中详细观测了在额定流量下，不同比重拍门的开启角度，水头损失及门体动水压力变化情况，以供工程设计应用参考。
The conclusion is that iron ceramics media has a lot of advantages over sand media in the fields of filter run and yield . it has good quality of little hydraulic pressure loss , longer period and capabilities of impurity 结果表明，涂铁陶粒滤料滤池具有过滤水头损失小、运行周期长、截污能力强的优点，其过滤性能优于石英砂滤料滤池。
A series of hydraulic model experiments of water flow , head losses and flow state in reservoir under various conditions are carried out for the design of the dashuzi pumped - storage plant 摘要本文结合大树子抽水蓄能水电站下库进出水口试验任务，对侧式短进出水口在不同工况下的流速分布、水头损失、库区流态等水流特性进行了水力模型试验研究。
Furthermore formulas of pressure loss are summarized based on trapezoid cell , this approach may be applied to study the mechanism of dissipative energy in other labyrinth emitters , and those regression formulas are tested through experiments 总结出以梯形单元为模块的水头损失公式，为研究其它迷宫滴头的消能机理提供了有效方法；通过试验验证了回归公式的可行性和准确性。
In the experiments , the primary shape is successfully optimized so as to make the hydraulic parameters better , the problems of lateral short inlet / outlet of pumped - storage plant in which water flow is asymmetric and head loss is too great are all resolved 对原设计体型成功进行了优化，使各项水力参数达到比较理想的效果，解决了抽水蓄能电站侧式短进出水口在出流时流态分布不均匀与水头损失系数偏大的难题。
( 2 ) feclsused as a coagulant when the water quality after filtration has tiny difference in the direct filtration process , compared with the finer sand media , the velocity increase of the water head loss of the coarser sand media is slower , and its filtration cycle is longer ( 2 )在直接过滤过程中，采用fecl _ 3作为混凝剂、出水浊度保持基本相同时，粗滤料的水头损失增长速度较慢，过滤周期比较长。 ( 3 )
By test data , variation of water head damage in filter lager and quantify of intercept filth in filter lager , filter cycle , analyse research of filter relation and data count by computer . i reach a mathematics relation among related coefficients 通过实验数据，对滤层水头损失的变化，滤层截污量，截污滤层阻力增长及过滤周期、滤速关系进行了分析研究，并利用计算机进行了数据统计，得出相关参数之间的数学关系。
The value of correction coefficient of kinetic energy increases as a result . the water surface profiles of flume experiments are computed by three different methods : adjusting the local head loss coefficient , deduction of backwater area , and application of backwater expression 随后结合实测水位资料，通过采用调整局部水头损失系数、扣除回水面积以及壅水公式等不同的水面曲线计算方法对实验水槽一维水面曲线进行计算。
It is more accurate than traditional method at the aspect of calculating head loss , pipe flow and node pressure of hydrant . this mathematic model can also be used in the inside and outside of water supply piping calculation and it is excel hardy cross - piping calculation 该方法在计算水头损失、管段流量、消火栓节点压力等方面比传统方法要更加准确，也可被借鉴到室内或室外的给水管网计算，并优于常见的哈代-克罗斯管网平差方法。
