一种利用共振声谱法检测气液两相介质中气体含量的新方法

Gas detection in a gas-liquid flow using an acoustic resonance spectroscopy method

根据共振声谱原理,建立了气液两相介质中圆柱共振腔共振声谱的实验测量系统,研究了共振腔体中不同含量的气体对共振声谱的幅度和共振频率的影响.实验结果表明:共振幅度和共振频率随着气体流量的增加都呈指数衰减变化趋势,但共振幅度比共振频率的衰减速度快,都可反映气体流量的变化.另外,在理论上,推导了均匀流体模型气液两相介质中的圆柱共振腔的共振频率计算公式,并模拟计算了共振频率和气体含量的变化规律曲线.理论研究结果表明,随着持气率的增加,共振频率减小;当持气率较小时,共振频率衰减较快.这一结论已经被本文实验测量结果所验证.理论和实验研究表明,利用共振声谱法可以检测气液混相介质中气体含量,它为发展生产井中气液两相流分相含量检测方法提供一种可能的途径.

Based on the theory of acoustic resonance spectroscopy （ARS）, the measurement system of the ARS is established for gas content detection in the liquid mixed with a gas. The resonance amplitude （RA） and resonance frequency （RF） are studied with various gas flow rate in a cylindrical resonance cavity. The experimental results show that ： the RF and the RA decrease with an exponent attenuation trend with the increase of gas flow rate passing through the cavity, and the attenuation rate of the RA is faster than that of the RF, although both of them are affected by the gas flow rate. Furthermore, the analytical expression for the RF is derived in a cylindrical cavity with a homogeneous flow model, and the curve of the RF with gas flow rate is numerically calculated. The results show that, the RF decreases with the increase of gas holdup. The attenuation rate of the RF is fast when the gas holdup is small. The theoretical and experimental results show that the ARS method could be used in gas detection in a gas-liquid medium, which paves a way for gas rate detection in a gas-liquid flow in a production well.