臺灣博碩士論文加值系統

中文摘要
本次實驗以高速攝影機(CCD camera)觀測牛頓流體及高分子水溶液(PEO)液滴碰撞到表面後之各種現象，如擴散(spreading)、飛濺(splashing)、迴縮(recoil)，藉著影像外觀變化的量測及其他儀器所測量出溶液之性質，對上述現象作定性及定量之分析。以不同重量百分比之甘油水溶液分析牛頓流體液滴從擴散到飛濺之能量關係，考量液滴本身黏度和擴散所代表作功的距離，更合理解釋”黏度抑制飛濺發生並不適用於任何條件。分析相同黏度下之高分子水溶液和甘油水溶液液滴飛濺發生高度和最大直徑，兩者均未發生飛濺之前，彈性效應對高分子溶液液滴影響非常小，但在有細絲牽引的飛濺現象中彈性影響非常明顯，根據如此臆測出上述現象之機構。對於高分子溶液之迴縮應先判斷出為彈性迴縮(elastic recoil)，再定義出相同濃度不同分子量高分子液滴迴縮之鬆弛時間(relaxation time)，與Zimm model之鬆弛時間正比於分子量1.5次方之關係比較，並配合濃度(c)與本質黏度([η])之乘積c[η]的關係以及影響分子鍊之拉伸(deformation)，判斷出本次PEO水溶液液滴迴縮狀態溶液由稀薄(dilute)到半稀薄(semidilute)分界點之c[η]界於2.25到4.5之間。

Abstract
The research is undertaken to observe the colloid phenomenon of the Newtonian fluids and polymer solutions (PEO) by CCD camera. For example：spreading, splashing and recoil. By measuring the variable shape of images, combined with observing the solution properties by other instruments, we could analyze the above phenomenon quantitatively and qualitatively. By preparing different weight percent of glycerin solutions as the Newtonian fluids for drops. Considering the viscosity of the drop and the distance influenced by spreading work, it provides ”the viscosity inhibits the splashing phenomena is not applicable to all conditions. By analysis the drop splashing height and maximum diameter of the polymer solution and glycerin solutions, the elastic effects influence very slightly before splashing, but in the ligaments attached condition the elastic influence is very huge. By this result, it’s predicted the mechanism of the above phenomenon roughly. Compared with Zimm model, the following dominant factors, concentration(C)*intrinsic viscosity([η]) and deformation of polymer chains, it’s judged the critical point C[η] between dilute and semidilute recoil polymer solution is from
2.25 to 4.5.

目錄
致謝
中文摘要
英文摘要
目錄--------------------------------------------------------------------------------I
附圖目錄-------------------------------------------------------------------------IV
附表目錄------------------------------------------------------------------------VII
符號說明-----------------------------------------------------------------------VIII
第一章 前言---------------------------------------------------------------------1
第二章 文獻回顧---------------------------------------------------------------3
2.1液滴碰撞研究方向及應用------------------------------------------------3
2.2液滴碰撞後之外觀現象---------------------------------------------------3
2.3各種描述影響牛頓流體液滴碰撞狀態的無因次群------------------5
2.4液滴擴散部分---------------------------------------------------------------5
2.4.1動能部分----------------------------------------------------------------5
2.4.2表面張力能-------------------------------------------------------------6
2.4.3黏度耗損能-------------------------------------------------------------8
2.5液滴最大直徑探討--------------------------------------------------------11
I
2.6液滴飛濺之探討-----------------------------------------------------------17
2.7液滴之迴縮與反彈--------------------------------------------------------19
2.8非牛頓流體液滴碰撞實驗之流體--------------------------------------24
2.9研究動機與目的-----------------------------------------------------------26第三章 實驗裝置與分析方法-----------------------------------------------27
3.1實驗裝置簡介--------------------------------------------------------------27
第四章 結果與討論-----------------------------------------------------------30
4.1牛頓流體液滴碰撞後擴散到飛濺巨觀現象--------------------------30
4.2各組甘油溶液之特性及無因次群分析--------------------------------31
4.3牛頓流體液滴臨界直徑之探討-----------------------------------------35
4.3.1達最大直徑時之能量耗損------------------------------------------38
4.4擴散到飛濺之能量分析--------------------------------------------------40
4.5碰撞表面之影響-----------------------------------------------------------43
4.6 PEO高分子水溶液液滴碰撞後影像之觀察-------------------------48
4.7細絲現象對飛濺之影響--------------------------------------------------51
4.8 PEO溶液飛濺與Mao et al model之關係----------------------------56
4.9 高分子水溶液液滴最大直徑之探討----------------------------------58
4.10高分子溶液液滴擴散到飛濺之能量分析---------------------------58
II
4.11液滴迴縮之探討-----------------------------------------------------------61
4.11.1高分子溶液液滴迴縮與 relaxation之關係--------------------61
4.11.2 Zimm model Rouse model對relaxation time之估計---------68
4.11.3本次實驗之relaxation time與Zimm model之比較----------69
4.11.4 dilute到semidilute--------------------------------------------------72
第五章 結論與未來展望-----------------------------------------------------75
參考文獻--------------------------------------------------------------------------77

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