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一、前言涡街流量计是一种新型流量测量仪表,在国内外发展极快,生产与应用量与日俱增。流体的体积流量与频率的基本关系为:在R_e=5×10~3～1.5×10~5范围内,S_t为一常数。因此涡街频率f与流体流速v成正比,与流体的物理特性无关;而且其流量比大,一般为10:1,可大到100:1。这就是它受到世人重视和发展极快的原因。通常情况下,涡街频率变送器的输出为正弦波信号,在实际使用中并非如此。它不止受流体紊流状态下速度脉动的影响,而且流体振荡及工
I. Introduction Vortex flowmeter is a new type of flow measurement instruments, developed rapidly at home and abroad, increasing the amount of production and application. The basic relationship between the volume flow and the frequency of the fluid is: S_t is a constant in the range of R_e = 5 × 10 ~ 3 ~ 1.5 × 10 ~ 5. Therefore, the vortex vortex frequency f is proportional to the fluid velocity v and the physical properties of the fluid has nothing to do; and its large flow ratio, typically 10: 1, up to 100: 1. This is why it has been valued and developed rapidly by the world. Under normal circumstances, the output of the vortex frequency transmitter is a sine wave signal, which is not the case in actual use. It is not only affected by the velocity pulsation in the turbulent state of the fluid, but also the fluid oscillates and works