The unsteady free water sheet flow in the rotating bucket of a Pelton turbine is a very complex flow that cannot be accurately simulated for lack of a numerical method.

冲击式水轮机水斗内非定常自由水膜的流动非常复杂，至今还没有足够精确的数值方法来模拟这种流动。

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Protection design for lower reaches of the Yellow River was once a difficult question due to high water head, various combinations of discharging structures, and complex flow pattern.

小浪底工程由于水头高、泄水建筑物组合多，水流流态十分复杂，下游防护设计是一难题。

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Impulse oxygen activation logging can be used to detect velocity and direction of water flow behind tubing. It is applied more and more in polymer injection Wells and complex completion Wells.

脉冲氧活化测井能在油管内探测管外水流速度及方向，在注聚合物井和复杂管柱结构井中的应用数量逐年增加。

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