upstream wall

The end face structure of a new type upstream pumping mechanical seal with double seal dams was developed because the solid particles were easily absorbed by the spiral groove type upstream pumping mechanical seal with the grooves on the internal wall to make the particles be damaged.

针对内径开槽的螺旋槽型上游泵送机械密封易于吸入固体颗粒而产生磨粒磨损的缺陷，研制开发出具有内外双密封坝的新型上游泵送机械密封端面结构。

The investigation of the upstream-downstream intermittent reversing flow in the near wall of a 2-D channel is attempted with a 2-D laser doppler velocimeter ( LDV).

本文应用二维激光多普勒测速仪（LDV），对二元通道内近壁间歇性反流特征做了尝试性测量。

In the experiment, the overflowing ability of gate, wing wall in the upstream and downstream of gate room, the rationality of plane distribution of diversion dike and protected bond range, and the rationality of distributing facilities for energy dissipation and erosion protection are studied.

试验对闸的过流能力、闸室上下游翼墙、导流堤的平面布置以及闸室上下游护砌范围的合理性、闸下消能防冲设施布置的合理性等进行了研究。

On this basis, the curve shapes and the formulas of upstream crest and downstream crest and those under the breast wall of the spillway dam are presented.

并以此为依据，提出有胸墙的溢流坝的堰顶上、下游及胸璃底缘的曲线型式和相应的计算公式。