机械通风逆流式无填料冷却塔内热交换过程的数值模拟-市政工程专业论文.docxVIP

西南交通大学硕士研究生学位论文 西南交通大学硕士研究生学位论文 第l页 摘 要 随着我国总人口的增加和城市化进程的加快及工农业生产等行业的发展，水的 需求量不断增加，使得我国水资源短缺与用水量不断增加之间的矛盾日趋突出。尽 管我国工业用水量只占总用水量的35．9％，但对国民经济的可持续发展具有举足轻重 的影响。因此工业节水是我国节水工作中一个重要的不可忽视的方面。其中通过设 置冷却塔则可实现冷却水的循环使用，这是一项经济有效的节水节能措施，有巨大 的经济效益和社会效益，也是工业节水的重要途径之一。 为了研究机械通风逆流式无填料冷却塔塔内的流场特性，在对无填料冷却塔的 工作原理、塔内液滴的运动过程及热量传递过程进行分析的基础上，建立了冷却塔 塔内流体传热及传质的数值计算模型，并采用FLUENT软件，对流体的传热和传质过 程进行了数值模拟，得出了冷却塔内流体流动的速度场分布图、温度场分布图、压 力分布图以及水滴运动轨迹线分布图。并计算分析了雾化喷嘴压力、进口风速等参 数对冷却塔塔内流体传热及传质的影响。 关键词：冷却塔；数值模拟：传热与传质 Abst Abst ract Accompanying the increasing of China’S population and the acceleration of urbanization，as well the development of industrial and agricultural production，the requirement of water increases unceasingly,and the contradiction between the water-shortage and the increasing of requirement becomes evident day by day．Although the industrial production demands only 35．9 percent of the total water consumption of C11ina．the influence of that on tlle sustainable development of the national economy is tremendous．Therefore the industrial water-saving in Our country iS an important aspect that call not be ignored．By applying cooling tower to realize the recycling of cooling water iS a cost-efrectiVe water-saving，i．e energy-saving，measures．It has enormous economic and social benefit，and iS one of the important ways of industrial water-saving． In order to study the flow．field characteristics of the filler-free cooling tower with an up—stream mechanical ventilation a numerical model of the heat and mass transfer of the cooling liquid in the tower was set up on the base of the analysis of the working principle of the cooling tower,the exercise process and heat transfer process of droplets．By FIUENT software a numerical simulation on the heat and mass transfer process of the liquid Was carried out．After studying the simulation a series of figures，which contain the distribution of velocity field，temperature field and pressure field of the liquid flow in the cooling tower and the distribution of the flow