輥輪塗裝過程出現在輥輪表面之流紋，基本上是塗料在輥輪間流動不穩定性所造成。在帶漆輥與塗覆輥間的順輥塗裝過程中，因塗膜分離流場不穩定而出現在塗覆輥表面之流紋，在來不及流平的情況下轉印到底材表面。
本研究乃利用二維暫態流體力學理論，以瞭解塗料在順輥塗裝過程的流動行為。首先採用不同濃度甘油溶液，考量在不同輥輪轉速比所求得之塗料厚度改變，並與在中鋼內所進行之實驗數據相比較。另亦針對目前生產線上之實際塗附之塗料，模擬在不同輥輪轉速比、塗料黏度、塗料表面張力與輥輪間之間距情況下，求得各參數對整體塗料流場與塗膜厚度之影響與關係。最後從模擬分析結果中求出輥輪塗膜厚度比與線速比之關係式。

When thin film of liquid is produced by rolling it is commonly observed that the resultant film is nonuniform in thickness or ribbed. The ribs are caused by flow instability bascially. The unlevel ribs caused by film-splitting are print to material surface in forward-roll coating.
The thesis utilized 2-D transient fluid dynamics theory to show how the behavior of flow fluid in forward-roll coating. At first, different concentration of glycerine solution is used. The change of thickness of coating under different rotation speed of the roll is measured. Then, the numerical results for different rotational speed ratio, viscosity, surface tension and gap of rollers during the process of forward-roll coating were discussed. Finally, we find the functional relationship between the film thicknesses and speed ratio.

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