此外，作物残茬、秸秆和牧草等粗糙元的高度、密度及直立性均对下垫面的空气动力学粗糙度、摩阻速度及风速脉动有一定影响。

In addition, the height, density and perpendicularity of remnant stubble, straws and grass had influence on aerodynamic roughness and wind velocity fluctuation on different underlying surfaces.

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在计算排出口压力计算过程中，考虑了由于抽油杆柱旋转引起杆管环空气液两相流摩阻的影响。

To calculate discharge port pressure, this article considers the influence on frictional pressure drop in the gas and liquid two-phase flow between rod and tubing owing to rotation of rods.

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