The level set method was used to numerically simulate the droplet formation process in T-junction microchannels with different junction angle. The effects of flow rate ratio, capillary number, and contact angle on droplet formation under different junction angles were discussed. The numerical simulation results show that the dimensionless length and generation frequency of microdroplets increase with the flow rate ratio. It was observed that the droplet transforms from the squeezing regime to the dripping regime when the capillary number Ca is ≥ 0.02. For Ca ≤ 0.04, the smallest droplet was generated in the microchannel with 120° junction angle. Finally, the results also indicate that the effect of the contact angle is discrepant at different junction angles.

中文翻译：

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不同结角 T 形入口微通道中液滴形成的模拟

采用水平集方法数值模拟了不同结角T型结微通道中液滴的形成过程。讨论了流速比、毛细管数和接触角对不同结角下液滴形成的影响。数值模拟结果表明，微滴的无量纲长度和产生频率随着流速比的增加而增加。观察到当毛细管数Ca ≥ 0.02时，液滴从挤压状态转变为滴下状态。对于Ca  ≤ 0.04，在微通道中产生最小的液滴，连接角为 120°。最后，结果还表明接触角的影响在不同的结角处是不同的。