水平管段塞流特征参数测量方法的试验研究

在内径 5 4mm、长 2 4m的水平有机玻璃管中利用空气水为试验介质对段塞流特征参数的测量方法进行了研究。利用上、下游两个压力信号相减得到差压信号 ,用电导探针测量了波高信号。分析了压力信号、差压信号和波高信号之间的对应关系 ,给出了利用差压信号相关测量液塞速度的方法 ,提出了“差压渡越时间”的新概念 ,并根据差压渡越时间这一概念提出了测量液塞长度的新方法。同时探讨了利用压力和波高信号测量段塞流特征参数的可能性和优缺点。试验结果表明 ,利用差压信号相关易于测量液塞速度、液塞频率和段塞单元长度 ,但用差压信号不能测量段塞流持液率的变化。液塞速度随气液混合物速度增大而增大 ,滑脱系数C0 不是一个常数。用波高信号相关可以测得液相平均速度。用波高和压力信号不易于测量液塞频率和段塞单元长度。

Experimental study on measuring characteristics of slug flow in horizontal pipe

The experiments on the characteristics of slug flow were carried out using a horizontal PVC pipe of 54 mm in diameter and 24 m in length, taking air-water mixture as media. The methods for measuring the slug characteristic parameters of slug flow were presented. The differential pressure signal was received using the difference between down-stream pressure signal and up-stream pressure signal, and liquid height was measured by electronic-conductance probe. The corresponding relationship among the pressure signals, differential pressure signals and liquid height signals was analyzed. A method for measuring the velocity of liquid slug using cross correlation of differential pressure signals was proposed. Based on this method, a new correlation of slug velocity was reached, and a new conception named "transition time of differential pressure signal" was put forward. The probability, virtues and shortcomings in determination of slug characteristic parameters using pressure signals and liquid height signals were discussed. The results show that it is convenient to determine the velocity, frequency and unit length of slug using the differential pressure signal. The liquid height signal can be used to measure the average velocity of liquid.