低流量条件下涡轮流量计的黏度响应特性

The Performance of Turbine Flowmeter with Viscosity Changes Under Low Flow Condition

搭建了一套用于低流量涡轮响应测量的实验平台。采用高速摄影对透明涡轮流量计的转动进行拍摄记录,可以对涡轮流量计在接近启动排量时的低转速响应特性进行有效测量。在此平台上对涡轮流量计在低流量条件下对不同黏度的流体响应情况进行研究,并结合传统涡轮流量计理论模型进行简要分析。在未达到线性响应段时,涡轮流量计K值与管道中流动的雷诺数近似呈指数关系。随着黏度的提高,涡轮流量计的启动排量呈下降趋势,且由加工偏心等因素造成的转动不稳定性亦随之下降。对于涡轮流量计而言,仅用一次高黏度条件下不同雷诺数的标定,即可近似得到其在不同黏度流动条件下的响应关系。

An experimental system is set up to investigate the performance of turbine flowmeter under low flow condition. Through the transparent shell the movement of turbine can be recorded with a high-speed camera. The behaviors of the turbine with different viscosities are examined and analyzed. It is found that the K factor of turbine {lowmeter increases exponentially with the increase of Reynolds number. Furthermore, the start-up flow rate and the instability of turbine＇s rotational speed decrease when viscosity goes high. So the response curves of turbine flowmeter with different viscosities might be proximately obtained through the calibration of different Reynolds numbers under high viscosity condition.