管壁材质对碳酸钙垢生长的影响及其机理研究  

The Effect of Tube Wall Material on Growth of Calcium Carbonate Fouling and its Mechanism

作　　者：李竑序 艾雄杰 王良璧[1,2] 常立民[1,2] 王良成[2,3] LI Hong-Xu;AI Xiong-Jie;WANG Liang-Bi;CHANG Li-Min;WANG Liang-Cheng(School of Mechatronic Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Key Laboratory of Railway Vehicle Thermal Engineering of Ministry of Education,Lanzhou 730070,China;School of Chemical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学机电工程学院,兰州730070 [2]铁道车辆热工教育部重点实验室,兰州730070 [3]兰州交通大学化工学院,兰州730070

出　　处：《工程热物理学报》2018年第12期2773-2778,共6页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51166007).

摘　　要：本文以CaCO_3的结晶污垢为研究对象,考察CaCO_3污垢在不同的壁面材质上结垢速率及其对传热特性的影响;观察壁面结晶污垢的形貌特征及其变化规律.实验结果表明:在循环工质为层流(Re=1381)的情况下,铝合金管材表面会生成一层由氧化铝构成的氧化膜,这导致铝合金管材表面结垢速率加快,并且结垢周期远远小于不锈钢管材上的结垢周期.而不锈钢管壁上没有氧化层出现,结垢前后其换热面的物理性质没有发生改变,管壁上所形成的晶体尺寸较大,晶型大多为生长完全的六面体方解石结构,但由于污垢沉积速率很慢,结垢周期较长,其晶体表面受到工质流体的剪切应力的影响和自身老化情况也较为严重.In this paper,the study is mainly focused on the crystallization of CaCO3 fouling and its contents include the following aspects:the effect of wall materials on CaCO3 fouling and heat transfer characteristics are investigated as well as the fouling mechanism of CaCO3 on the heat transfer wall,and the morphological characteristics of the crystal fouling are also observed. Experimental results show that:under the laminar flow of the circulating working fluid conditions (Re=1381),a film of alumina oxide will form on the wall of aluminum alloy pipe,resulting in faster fouling and much shorter the fouling period than that on the stainless steel pipe;however for the stainless steel pipe there is no oxide layer on the pipe wall,the physical properties of the pipe wall are not changed before and after fouling,moreover the crystal size is large and morphologies of CaCO3 scale is mainly hexahedral calcite,while the fouling deposition rate is much slow,these are due to both the effect of the fluid shear stress and the impact of fouling aging on the fouling surface.

关 键 词：管壁材料 污垢沉积 生长机理 碳酸钙 

分 类 号：TK123[动力工程及工程热物理—工程热物理]