超声波风速仪工作原理.doc

文档介绍：The Anemometer measures the times taken for an ultrasonic pulse of sound to travel from the North transducer to the South transducer, pares it with the time for a pulse to travel from S to N transducer. Likewise times pared between West and East, and E and W transducer.
If, for example, a North wind is blowing, then the time taken for the pulse to travel from N to S will be faster than from S to N, whereas the W to E, and E to W times will be the same.
The wind speed and direction can then be calculated from the differences in the times of flight on each axis. This calculation is independent of factors such as temperature.
风速仪会测量超声波脉冲从感应头N(北)到感应头S(南)的传递时间,和从感应头S到N的传递时间相比较;同时比较从感应头W(西)到E(东)和从E到W的传递时间。比如,风向为北风,则脉冲从N到S要比从S到N传递的快,但从W到E和从E到W的时间应该相同。
参考上面的工作原理图,风速和方向就可以通过每个轴向的传递时间差异计算得出。这种计算方法不受诸如温度等因素的影响。
--引自Gill 风速仪手册