| 摘要 |
Determining interfacial tension between first and second immiscible liquids, comprises directing a flow of the first liquid surrounded by a flow of the second liquid into a succession of three channels comprising an entrance channel 18, a cavity 20 and an exit channel 22. The cavity 20 connects the entrance and exit channels and has a wider cross-section for flow than both the entrance and exit channels, such that the first liquid enters the cavity as a jet 24 and breaks into droplets 26 within the cavity, such that passage of a droplet through the exit channel creates a perturbation which feeds back to perturb the jet entering the cavity. An alternating signal is supplied to perturb the incoming jet 24 of the first liquid at the frequency of the supplied alternating signal. The frequency of the supplied alternating signal is varied over a range while observing the frequency of droplet formation, so as to determine a frequency bandwidth within which formation of droplets takes place at the frequency of the supplied signal. A ratio of the resonant frequency to the bandwidth may be determined. |
