文丘里洗涤器内气液两相流的压降特性研究

Study on Pressure Drop Characteristics of Gas-Liquid Flow in Venturi Scrubbers

通过实验和CFD数值模拟相结合的方法,研究文丘里洗涤器内气液两相流压降特性。实验测量不同喉管长度、气体流量、液气比和喷嘴喷淋形式下,文丘里洗涤器压降的变化规律;建立CFD数值模型并验证其可靠性,考察文丘里洗涤器内液滴速度和浓度、管内压力和湍流强度的分布规律。研究结果表明,文丘里洗涤器内气液两相压降随气流量和喉管长度增加近似呈线性增加;采用轴流实心喷嘴产生的压降要大于采用轴流空心喷嘴产生的压降;压降随液气比增大而增大但不同液气比下变化速率不同;喉管段加速液滴和扩张段湍流强度的增大是长喉管和高气液比下压降大的主要原因。

The experimental and CFD numerical simulation methods were combined to study pressure drop characteristics of the gas-liquid flow in a venturi scrubber.Measuring the venturi scrubber’s pressure drop rule under different throat lengths,gas flow rates,liquid-gas ratios and nozzle spray forms was performed,including establishing CFD model and verifying its reliability,investigating the distribution rule of droplet velocity and concentration,pressure and turbulent intensity in the venturi scrubber.The results indicate that,the gas-liquid pressure drop in the venturi scrubber increases approximately linearly with the increase of gas flow rate and throat length.The pressure drop of the venturi equipped with an axial solid nozzle is greater than that equipped with an axial hollow nozzle;the pressure drop increases with the rise of liquid-gas ratio,but the rate of change varies at different liquid-gas ratios.The main reason for the large pressure drop in the long throat and high air-liquid ratio is the increase of the acceleration droplet and the turbulence intensity in the expansion section of the throat.