暫態流體黏度量測法

Abstract

本文以探棒式黏性測量系統，進行擠壓/拉伸兩用式流變儀之開發與探討。吾人利用尺寸較小的探棒取代傳統所使用的平板，可以達到15-5μl低流體耗量與8秒以內完成測量的優點。本研究首先進行擠壓與拉伸流體的力學定量分析，證實在磨潤近似的條件下史考特理論適用於擠壓與拉伸的實驗結果，並說明如何校正荷重元的柔度與阻尼效應帶來的影響。實驗結果配合本文中提出的流變特性暫態量測法，可快速的計算出實驗流體的流變特性。測量結果發現，矽油的測得之黏度值與標準值相比誤差平均在5%以內；而對於非牛頓流體的流變特性，亦能在高剪應變速率區間中測出對應的流變趨勢，證實此一方法可以適用於牛頓流體與符合剪切稀釋特性的非牛頓流體之黏度測量上，成功發展出一套低耗量且快速的擠壓/拉伸兩用式流體黏度測量系統。除了黏度測量之外，本研究亦由力學觀念上解釋擠壓與拉伸黏性流體中發生的各種應力反應，作為日後在黏彈性體定量分析上的基礎。

In this study, we established a probe tack tester to measure fluid rheological properties by this miniaturized squeezing & stretching system. Instead of traditional plate, I used a smaller probe which had the advantages of low fluid & time consumption. First, we studied the mechanism of squeezing & stretching test quantitatively, and we found the Scott theory can predict experiment results well under the lubrication conditions. And then we explain how to calibration the compliance and damper effect of the transducer. The experimental results with the transient measurement method, which proposed in this thesis, can calculated the rheological properties of the fluids. The measurement results found the error between the standard value and measured value of silicone oil viscosity within 5%, and for the rheological properties of the non-Newtonian fluid, the measured rheological trends also corresponding the standard value in the high shear strain range, it shows this method can be applied in the measurement of the viscosity of the Newtonian fluid and non-Newtonian fluid, with the advantages of low fluid & time consumption. In addition to the measurement of viscosity, mechanical concept is also explained of various experiments, as the based on the quantitative analysis of the viscoelastic squeezing and stretching viscous fluid.