提出一种具有4个分流喷嘴的新型取样器结构,根据分流比和取样流体气、液流量确定主管路气液相流量。为保证取样流体的代表性,采用"流型调整"与"阻力控制"两种方法抑制相分离的发生。建立气液两相流数值模型,模拟气液两相流在取样器中的流动特性。在气液两相流试验环道上开展试验测试,流型包括波浪流、段塞流及环状流。结果表明:在试验范围内气、液相分流系数接近理论值0.25,其主要取决于分流喷嘴的数目,不受流型、气液流速等参数波动的影响,流量测量误差小于±6.0%。该取样计量装置具有体积小、精度高、维护费用低的优点,可代替传统计量分离器,实现气液流量的实时测量。
A novel sampler with four nozzles was proposed to extract a small fraction of gas liquid mixture from the main stream. The total gas and liquid flow rate was determined according to the flow rate of the sampled fluid and the extraction ratio. A gas-liquid two-phase flow numerical model was developed to simulate flow characteristics of gas-liquid two-phase flow in the sampler. Experiments were carried out in an air-water two-phase flow loop. The flow patterns observed during the tests includes wavy flow,annular flow and slug flow. The experimental results show that the gas and liquid flow is close to the theoretical value of 0. 25 and is independent of inlet quality,flow pattern,gas and liquid velocity. The measurement error of flow rates is less than ± 6. 0%. The metering device proposed has the merits of small size,low cost and high accuracy and can replace conventional metering separator for online measurement of gas-liquid two-phase flow.