化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2015年
7期
2450-2455
,共6页
多孔介质%介尺度%形态%接触角%临界含湿率
多孔介質%介呎度%形態%接觸角%臨界含濕率
다공개질%개척도%형태%접촉각%림계함습솔
porous medium%mesoscale%morphology%contact angle%critical liquid content
实验研究了不同含湿率时堆积颗粒聚集状态和试样表观体积的变化,并分析了内在影响机理。含湿率较低时液体在试样内部的主要存在形式为液桥,含湿率较高时液体主要以联通液的形式存在,两种形态水分发生转换的临界含湿率由水在颗粒表面的表观接触角决定。试样内部液体形态及分布的演化,导致液体对颗粒的作用力发生变化,进而影响颗粒的聚集状态以及试样的宏观表观体积变化。利用建立的模型推导了液体形态发生转换的临界含湿率与表观接触角之间的函数关系,计算结果与实验具有较好的一致性。
實驗研究瞭不同含濕率時堆積顆粒聚集狀態和試樣錶觀體積的變化,併分析瞭內在影響機理。含濕率較低時液體在試樣內部的主要存在形式為液橋,含濕率較高時液體主要以聯通液的形式存在,兩種形態水分髮生轉換的臨界含濕率由水在顆粒錶麵的錶觀接觸角決定。試樣內部液體形態及分佈的縯化,導緻液體對顆粒的作用力髮生變化,進而影響顆粒的聚集狀態以及試樣的宏觀錶觀體積變化。利用建立的模型推導瞭液體形態髮生轉換的臨界含濕率與錶觀接觸角之間的函數關繫,計算結果與實驗具有較好的一緻性。
실험연구료불동함습솔시퇴적과립취집상태화시양표관체적적변화,병분석료내재영향궤리。함습솔교저시액체재시양내부적주요존재형식위액교,함습솔교고시액체주요이련통액적형식존재,량충형태수분발생전환적림계함습솔유수재과립표면적표관접촉각결정。시양내부액체형태급분포적연화,도치액체대과립적작용력발생변화,진이영향과립적취집상태이급시양적굉관표관체적변화。이용건립적모형추도료액체형태발생전환적림계함습솔여표관접촉각지간적함수관계,계산결과여실험구유교호적일치성。
The particles aggregation states and apparent volume of the stacked glass beads at different liquid content are studied experimentally. It shows that the liquid mainly exist as liquid bridges at low liquid content, while that in different pores connects to each other at higher liquid content. The apparent contact angle of water on particle surface determines the critical moisture content which separates the low and high moisture content. The transformation of liquid morphologies induces the variation of the liquid action on particles, which finally influences the particles aggregate state and leads to the change in the sample apparent volume. A model is developed to determine the critical liquid content by the apparent contact angle, from which the liquid begins to mainly exist as interconnectedness morphology other than isolated liquid bridges. The prediction from the model is in good agreement with the experimental data.