王晓静,王鑫鑫,张 伟
AuthorsHTML:王晓静，王鑫鑫，张 伟
AuthorsListE:Wang Xiaojing,Wang Xinxin,Zhang Wei
AuthorsHTMLE:Wang Xiaojing，Wang Xinxin，Zhang Wei
Unit:天津大学化工学院，天津 300350
Unit_EngLish:School of Chemical Engineering and Technology，Tianjin University，Tianjin 300350，China
Abstract_Chinese:针对传统干燥过程存在的弊端，设计开发了回转锥筒非相变脱水干燥机，将多孔材料内衬到回转锥筒，通 过多孔材料毛细作用快速吸附湿物料携带的表面水分，以达到物料快速脱水的目的．为了研究多孔材料的吸附性 能，应用描述多孔介质内部液相毛细上升高度随时间变化的数学模型进行数值计算，研究了多孔材料颗粒直径以及 孔隙率对毛细吸水过程的影响．在理论研究的基础上，以多孔陶瓷为研究对象，研究数学模型的可靠性并分析多孔 材料毛细吸水特性的影响因素．结果表明：数值计算与实验结果有较好的一致性，颗粒直径与多孔材料孔隙率是影 响毛细吸水特性的主要因素．颗粒直径越大，多孔材料毛细吸水速率越大，毛细吸水高度越低．这是因为渗透率 k 与颗粒直径 d 的平方成正比关系，颗粒直径越大则渗透率也大，因此其毛细吸水速率大；同时颗粒直径越大，其内 部孔隙结构相对越大，较大的孔隙结构使毛细水上升通道变大，因此其毛细吸水高度越低．孔隙率越大，多孔材料 毛细吸水速率越大，毛细吸水高度越低．这是因为渗透率 k 随孔隙率ε 的增大而增大，因此其毛细吸水速率越大； 同时在颗粒直径相同的情况下，孔隙率越大其内部孔隙结构相对越大，较大的孔隙结构使毛细水上升通道变大，因 此其毛细吸水高度越低．
Abstract_English:In view of the disadvantages of the traditional drying process，a non-phase-change rotating cone dryer was designed. Porous materials are used to line the rotating cone，and the surface moisture of wet materials is absorbed through the capillary action of porous materials to enable the rapid dehydration of materials. To analyze the absorption properties of porous materials，the mathematical model describing the change of capillary water absorption height with time in porous media is applied. The influences of the particle diameter and porosity of porous materials on the capillary water absorption process were investigated by numerical calculation. On the basis of theoretical research， taking porous ceramics as the research object，the reliability of the mathematical model is assessed and the influenc\u0002ing factors of the capillary water absorption characteristics of porous materials are analyzed. Results show that the numerical calculation is consistent with the experiments. The particle diameter and porosity of porous materials are the main factors affecting the capillary water absorption characteristics. The larger the particle diameter is，the higher the capillary water absorption rate of porous materials and the lower the capillary water absorption height. This finding can be attributed to the fact that permeability k is directly proportional to the square of particle diameter d. The larger the particle diameter is，the higher the permeability. Therefore，the capillary water absorption rate is high. At the same time，the larger the particle diameter is，the larger the internal pore structure. Therefore，the capillary water absorption height is low. The higher the porosity is，the higher the capillary water absorption rate of porous materials and the lower the capillary water absorption height. This finding can be attributed to the fact that permeability k in-creases with the increase in porosity ε. Therefore，the capillary water absorption rate is high. At the same time，the higher the porosity is，the larger the internal pore structure. Therefore，the capillary water absorption height is low.
Keyword_Chinese:多孔陶瓷材料；毛细吸水；理论模型；颗粒直径；孔隙率
Keywords_English:porous ceramic material；capillary water absorption；theoretical model；particle diameter；porosity

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