多孔介質浸潤機制研究

Investigating Imbibition Mechanism in Porous Media

陳彥伶(Yen-Ling Chen)

指導教授 ： 蘇淵源

國立臺北科技大學/工程學院/化學工程研究所/碩士(2013年)

摘要

纖維強化複合材料製程中，避免氣泡生成是重要的製程因素。氣泡可能生成並形成空洞在成品當中。這些空洞會導致機械性質下降並且產生缺陷。所以本研究利用數值分析與實驗方法探討流體於多孔介質中的浸潤行為。
本文主要以有限差分法FLOW-3D及飽和浸潤實驗，探討流體於玻纖中的毛細行為及飽和度變化。我們以實驗求得重要的模擬參數，利用ASTMC948 – 81量測玻璃纖維的基本材料參數。以離心法(centrifuge method)測得毛細壓力與飽和度之關係。以滲透率實驗(wicking test)測得材料的滲透率(K)，進一步計算飽和拖曳係數(Do)。實驗所求參數除了供應模擬數值，也可藉由類達西定律(Modified Darcy’s law)建立理論模型來預測浸潤速度。
實驗部分，我們建立飽和浛浸實驗(saturation test)得知流體於玻纖中任一時間的飽和度變化，並且與FLOW-3D及理論模型結果做比對，發現數值分析結果與實驗結果相近，因此，實驗與模擬相輔相成，印證模擬並預測趨勢為本研究之目的。另外以SEM截圖計算PTFE-玻纖膜之覆蓋率(cover factor)，分析流體以自然毛細壓力浸潤玻纖的成品情形。

關鍵字

毛細壓力 ； 滲透率 ； FLOW-3D ； 多孔

並列摘要

In the process of fiber-reinforced polymer composites, avoiding bubbles formation is an important factor. Air bubbles are possibly generated and remain as voids in the product. The voids result in a decrease of the mechanical properties and defect formation. In this work, the imbibition phenomenon of flow in porous media is studied by numerical and experimental methods.
This article studied the capillary behavior and the evolution of saturation in glass fiber fabric by using the Finite Difference Method FLOW-3D and the experiment of saturation test. Several important parameters required in numerical simulations are determined experimentally such as porosity, permeability and capillary pressure in compliance with ASTM, wicking test and centrifuge method, respectively.
Our analyses show that Modified Darcy’s law can appropriately predicts imbibition rate and the compact correlation between those experimental parameters used in Modified Darcy’s law exists. Finally, it is demonstrate the experimental data of saturation test is successfully predicted by the numerical result.

並列關鍵字

capillary pressure ； permeability ； porous media

參考文獻

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