【摘 要】
：
传统的超声Doppler流量计在管道流量测量中会遇到无法判断流速方向和低流速测量困难等问题。该文基于虚拟仪器平台,将Doppler信号解调到15kHz的中心频率,并运用Zoom-FFT算法
【机 构】
：
清华大学精密仪器与机械学系,深圳清华大学研究院,深圳清华大学研究院 北京100084,深圳518057 ,深圳518057
论文部分内容阅读
传统的超声Doppler流量计在管道流量测量中会遇到无法判断流速方向和低流速测量困难等问题。该文基于虚拟仪器平台,将Doppler信号解调到15kHz的中心频率,并运用Zoom-FFT算法对其进行高精度选带频谱分析,然后进行加权平均频率估计,得到被测流体的平均流速及方向,实现了一个新的超声Doppler流量测量系统。超声波探头外夹安装在充满流体介质的不锈钢管道上进行流量测量,实验结果表明该系统不仅可以正确分辨流速方向,还能测量低达0.02m/s的流速,在判断流速方向和低流速测量上比传统超声Doppler流量计更为有效。
Traditional ultrasonic Doppler flowmeter in the pipe flow measurement will be unable to determine the flow direction and low flow measurement difficulties and other issues. Based on the platform of virtual instrument, the Doppler signal is demodulated to the center frequency of 15kHz and the spectrum is analyzed using Zoom-FFT algorithm. Then the weighted average frequency is estimated to obtain the average velocity and direction of the measured fluid , A new ultrasound Doppler flow measurement system was implemented. The ultrasonic probe is mounted on a stainless steel pipe filled with a fluid medium to measure the flow rate. The experimental results show that the system not only can correctly distinguish the flow direction, but also can measure the flow rate as low as 0.02 m / s. When judging the flow direction and low flow rate More effective than traditional ultrasonic Doppler flowmeters.
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