旋流条件下的气液环空流流动规律研究

针对涡流工具排液效果的问题，开展了旋流条件下气液两相流动模型的研究。考虑到旋流中角速度的存在，研究中采用气液流动在径向和周向上的动量和角动量平衡的方法，建立了气液流动控制方程，计算了液膜厚度，气液相旋流强度等参数以及压降梯度，并进行涡流工具实验验证模型。涡流工具降低压降损失的机理结果表明，安装涡流工具后流动压降可以降低5%~20%。根据实验及模型，在低速（气相速度小于13 m/s）时，小旋流角和高旋流强度更利于降低压降，而高速（气相速度大于16 m/s）时，高旋流强度会增加额外摩擦阻力。旋流强度的衰减速度会随着液相速度增大而减小，而随气相速度增大而增大。该研究结果可对涡流工具进行优化设计，以达到最佳排液效果。

Study on the Gas-liquid Swirling Annulus Flow with the Vortex Tool

In order to explain the unloading effect of vortex tools, it is necessary to establish a gas-liquid two-phase flow model in accordance with its flow law. Considering the existence of angular velocity in vortex flow, this research adopts the radial and circumferential momentum and angular momentum balance of gas-liquid flow, the governing equation of gas-liquid flow and the parameters such as liquid film thickness, gas-liquid vortex intensity and pressure drop gradient are obtained. The vortex flow experiments are conducted to verify the model. The results of model calculation and experiment show that the pressure drop of gas-liquid flow can be reduced by 5%~20% after the vortex tool, and the mechanism of reducing pressure drop loss by vortex tools is also given. According to experiments and models, it can be concluded that small vortex angle and high vortex intensity tend to reduce pressure drop at low velocity(gas velocity is less than 13 m/s), while high vortex intensity increases additional friction resistance at high velocity(gas velocity is faster than 16 m/s). The decay rate of vortex intensity decreases with the rise of liquid phase velocity and increases with the rise of gas phase velocity. Therefore, based on the research, vortex tools can be optimized to achieve the best liquid unloading effect.