摘要
悬索缆道测流，往往使流速仪形成垂直偏角，对流速有一定影响。分别率定了ＬＳ２５－１型旋桨流速仪和ＬＳ６８－１型旋杯流速仪在不同下倾角时与流速的关系：流速仪的垂直偏角对流速有明显影响，并随偏角的加大而增加，偏角在１０°以内影响不大；同时也率定了 ＬＳ６８－１型旋杯流速仪自动调整垂直下倾角时与流速的关系，下倾角在１０°～３０°以内对流速无明显变化，超过３０°时，流速系统偏小。解决办法是：（１）流速小有偏角时用 ＬＳ６８－１型旋杯流速仪，流速大时用 ＬＳ２５－３型旋桨流速仪，二者均有自动调平的功能；（２）治理选择铅鱼的型式和重量，本文提供了数据。
The current meter, when measuring flow velocity with a suspended cableway, always composes a vertical angle which affacts result of velocity measurement.Various relationship between dip angle and flow velocity of M25-1 vertical-axis current meter and LS68-1 horizontal-axis current meter is discussed. The research shows that the larger vertical dip angle results in the larger error of the now velocity. Flow velocity of LS68-1 horizontal-axis current meter is acceptable when dip angel is within 10 to 30 However,the measuring velocity is systematic shifting smaller when the dip angle is over 30 comparing with the actual velocity. Two methods that may narrow the error of measuring flow velocity are discussed.1).The LS68-1 horizontal-axis current meter is recommended when the dip angle is small,and LS25-1 vertical-axis current meter can be used when the dip angle is large.2).Choose suitable lead fish with reasonable type and weight.
出处
《水文》
CSCD
北大核心
2000年第1期31-34,共4页
Journal of China Hydrology
关键词
流速仪
偏角
测速
误差
velocity meter
dip angle
effect
