利用壓電致動器成型穩定微液滴之 實驗研究

The study on the formation of stable micro-liquid droplet—by the using of piezoelectric transducer

陳威翰(WEI-HAN CHEN)

指導教授 ： 王興華

國立臺灣大學/工學院/機械工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.10385

摘要

本文針對不同大小之壓電晶片進行壓電式液滴產生器的結構設計及性能測試，並建立一套液滴產生觀測設備，經由改變多種參數，且藉由攝影所擷取的瞬間影像來了解液滴產生之行為，著重於觀測液滴產生之動態過程並取得穩定成型之訊號範圍與成型的粒徑、速度、時間等資訊，期能提供微液滴產生現象明確而充分的資料，進而對產生液滴成型機制有進一步的研究探討。

過去對液滴產生之研究雖多，卻極少完整的比較不同參數下的成型特性及確切的穩定範圍，本實驗的控制參數為液滴產生器大小、液料性質、噴嘴孔徑及形狀、操作頻率及意外發現的訊號正反向輸入。

本實驗主要探討三部份:一為不同液滴產生器大小配合油料改變對成型現象的影響；二為製作同孔徑但出口形狀極端的噴嘴配合油料改變對成型現象的影響；三為訊號的反向輸入使壓電晶片反向變形的成型特性分析，最後將實驗數據加以分析。

關鍵字

壓電 ； 液滴產生器 ； 微液滴 ； 衛星液滴

並列摘要

This text aims at different size of piezo wafer to giving an structure design and performance test for piezoelectric droplet generator, and build up a set of device to observe , through change various parameters and gather the moment image by CCD camera to understand produce the droplet, put great emphasis on gauging the dynamic state process of produce the droplet ,then obtain stability shaping signal range and information (like diameter, velocity, broken time etc…) for shaping, wish to provide explicit and full data for micro-droplet producing phenomenon, and then to go a step further investigate and inquire to droplet producing .

Although in the past there was many research of droplet producing, but the complete compare for shaping property under different parameters and accurate stable range was less. The control variable of this experiment are size of droplet generator, fluid properties, shapes and bore diameter of nozzle, operation frequency, and a windfall two-way signal input.

This experiment mainly inquires into three parts : one is the different size of droplet generator match up fluid properties influence of droplet shaping phenomenon, the other is nozzle have the same bore diameter but different outlet shape match up fluid properties influence of droplet shaping phenomenon, last is the shaping property analysis for piezo wafer change shape opposite by signal input opposite, then analyze the experiment data.

並列關鍵字

piezoelectric ； droplet generator ； micro-droplet ； Satellite drop

參考文獻

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