In this thesis , the law of reduction friction and the law of prolong the transportation distance are discussed and the formula of prolong transportation distance rate has also been obtained 而且，本文探讨了加气减阻和延长排距的机理，提出了加气延长排距百分数公式。
The c . e . in both 2d and 3d problem increase the lifting forces , the c . e . in 3d problem decreases the " drag coefficients , but the c . e . in 2d increases the drag a little 波动效应也随着高度的增加而减少，但是和曲壁面效应相比，衰减速度要小得多。波动效应具有减阻作用。
From above schemes , the experiment of reduced resistance has been done under the condition of different velocity of different velocity , different gas flux , waterline and so on 针对以上所设计的试验方案进行了不同速度、不同喷气量及不同吃水等情况下的微气泡减阻试验。
The results predict the local friction reduction increases with the air injection ration hut decreases with the distance - away from the injection , which is in conformity with experiments 结果预示，随着喷气率增大，局部减阻率增加，但离喷气口的距离越远，局部减阻率减小。
It shows that the collapsing of loose avalanche soil is due to mixing of avalanche soils and water flow , and the collapsing of block avalanche soils is caused by resistance decrease due to overload pore water pressure 实验表明：松散崩塌土流动化机理为水流掺混，块状崩塌土流动化机理为压差减阻。
It is found that drag reduction occurs with adequate wavenumbers and grows with an increase of h . the mechanisms are revealed through variations of velocity profile and the decrease of wall shear stress 分析减阻机理是流速分布曲线及近壁区速度梯度介于层流与湍流之间， h值增大引起壁面剪应力显著下降。
The construction proposal recommended by this research project suggests a gradual increase in installation of boosting pump and tank , in conjunction with the use of dra as an expedient be utilized to accomplish the ever increasing throughput 课题研究所提出的管道建设方案，主张以不断增设增压站、储罐、输送工艺中采用添加减阻剂的方式，来满足输送量日益增多的需要。
Besides , as results shown under considering factors affecting the friction reduction , with the increase of microbubble diameter within 100 ? w and the grads of air volume fraction in injection normal to the plate , the magnitude of friction reduction will be increased 此外，对影响减阻的因素计算结果表明，随着气泡直径( 100 m以内)和入口处气泡体积浓度的垂向梯度增大，减阻量增加。
The research will reduce engineering cost by 15 yuan / m ^ 2 , to increase the amount of transporting water of the middle route project of the south north water diversion to 1 , 500 million liter annually , which can bring 30 , 000 million yuan income at least 通过研究可将减阻降糙处理工程造价控制在15元平方公尺以下，以南水北调干线中线每年新增15亿立方公尺流量，运营按20年计，至少可带来300亿元收益。
The numerical simulations are consisted of two parts : the first is to simulate the friction reduction by microbubbles on a flat plate ; the second is to simulate initially the friction reduction on the approximated ship model with the flat bottom 本文对微气泡减小表面摩擦阻力的现象进行了数值计算。数值模拟分成两个部分：第一部分是平板微气泡减阻的数值模拟；第二部分是平底近似船模数值模拟的初探。
