壓電噴墨系統可以透過電腦輔助控制直接進行參數的調整，受到不同噴墨參數如：波形、電壓和頻率等所影響，會有不同的微液滴行為。為了改善製程速度及噴印品質，各種影響噴墨過程的參數皆需要得到適當的控制。
本研究使用FLOW-3D®套裝軟體進行數值模擬並結合實驗驗證，針對單脈衝波形中的脈衝時間TRise、TDwell、TFall進行研究，探討TRise、TDwell與TFall對噴墨管中壓力波、液滴飛行速度及液滴體積的影響。
由研究結果發現，隨著TRise、TFall(=2~16 μs)的增加，液滴飛行速度和液滴體積皆與TRise、TFall呈現線性關係；TFall的增加，使得液滴飛行速度有較大的上升趨勢，TRise的增加，使得液滴體積有較大的上升趨勢。
透過實驗和數值模擬系統的比對，得到符合實際噴墨管的最佳波寬時間(Optimum Pulse Width)，代入最佳波寬時間後，分別可以在噴嘴端得到最大正壓力值，以及得到最大液滴飛行速度。

Inkjet printing technology has been widely used in many applications. Piezoelectric inkjet printing system could be directly modulated by computer control. Behaviors of droplet are affected by various parameters, such as: driving waveform, pulse voltage and frequency. In order to improve the processing throughput and printing quality, the droplet stability and speed need to be well controlled.
This study presents numerical analysis and experiment results of droplet formation process in squeeze-mode piezoelectric inkjet printhead. The effects of different pulse time on droplet formation and droplet velocity in unipolar waveform were investigated.
The results show that droplet velocity and droplet volume both increased with increasing TRise or TFall. Comparing the different contribution of each parameter, the droplet volume is more sensitive to TRise than that in TFall. In addition, TFall has much more impact on the speed of the droplet than TRise.
Through the numerical simulation results and experimental verification, the optimum pulse width of piezoelectric inkjet tube could be obtained.. Under the optimum pulse width, the droplet velocity and pressure wave can both reach the maximum value.

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