采用高速摄像仪对不等宽T型分岔微通道中气泡的破裂和体积分配规律进行了研究,分别考察了气液流量与液相黏度对气泡分配规律的影响,同时研究了子气泡对气泡破裂的反馈效应。结果表明:由于微通道下游子气泡对分岔口处气泡破裂的反馈效应,两个子气泡体积分配比V2/V1随气液流量比的增大呈先增大后减小的非线性变化趋势。随无量纲母气泡体积V0/w0^2h的增大,V2/V1也呈先增大后减小的变化趋势,并且存在一个临界无量纲母气泡体积(V0/w0^2h)c。在实验范围内,气液流量比对(V0/w0^2h)c的影响较大,而液相黏度对(V0/w0^2h)c的影响可以忽略。提出了子气泡体积分配比的关联式,计算值和实验结果吻合良好。
Bubble breakup and volume distribution in a T-junction with unequal width bifurcations were observed and investigated by a high-speed camera. The influences of gas, liquid flow rate and liquid viscosity on bubble distribution during breakup were also studied. The results show that the volume distribution ratio of two daughter bubbles V2/V1 non-linearly increases at first, and it then decreases with the increase of gas to liquid flow rate ratio due to the feedback effects. Similar tendency was also found in the study on the effects of dimensionless mother bubble volume on V2/V1, and there exists a critical dimensionless mother bubble volume which is dependent on gas-liquid flow rate ratio, but nearly independent on liquid viscosity. Two correlations were proposed to predict the volume distribution of daughter bubbles, and the calculated results show good agreement with experimental data.