本研究以可程式函數產生器將方波加以修改並經由壓電液滴產生器對液柱產生對應之液滴斷裂，藉以觀察在不同波形效應影響之下自由液柱的斷裂模式與其斷裂後衛星液滴的產生，探討在特殊的波形效應差異對於斷裂行為的影響，實驗中並觀察液柱在受到不同波形效應振盪下斷裂時之斷裂長度。進而尋求一最佳之外加擾動波形，以得到最穩定之液滴粒徑及均勻間距之液滴串。
實驗結果顯示，外加震波波形之不同，液柱斷裂後的液滴群組組成有形成均勻的液滴分佈，或是在主液滴之間另具有衛星液滴等數種型態，其型態的形成原因則和液柱斷裂時的形狀具有直接的關係。
實驗中另就自由液柱受到外加方波可產生均勻斷裂的頻率附近採取另一組頻率，利用此頻率的方波對自由液柱作震盪，可使液柱產生具有衛星液滴的非均勻斷裂，在此情形下採取不同的合成波形震盪模式操作條件，尋求一最佳之外加擾動波形，使得在低速噴流的應用中能夠得到預期液滴粒徑及均勻間距之液滴串。
實驗結果顯示間歇式波形效應不同之試驗波形對液柱加以震盪下，於液柱斷裂部位並未發生第二次斷裂或是產生衛星液滴，其具有改善液柱斷裂之效果。

In order to observe the liquid jet breakup and the formation of satellite droplet after breakup under the influence of different waveforms, a programmable function generator was used to modify square waves and to drive a piezoelectric droplet generator. The influence of a particular waveform on the breakup length and the breakup type of a liquid jet were studied.
The results demonstrate that with different applied vibrating waveform, there are four basic breakup types of a liquid jet, namely, X, A, V and O. Whether the pattern of droplet series after liquid jet breakup results in even size and spacing droplets, or has various patterns of satellite droplets between the main droplets, is directly related to the liquid jet breakup type.
At a frequency at which square wave vibration would result in uneven breakup droplet pattern with satellite droplet, we take different modified waveforms to vibrate the liquid jet and search for a better waveform to eliminate the satellite and to obtain uniform droplet size and even spacing. We found that an intermittent square wave can give the best result.

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