【作者】 刘东亮；

【导师】 史晓平；

【作者基本信息】 河北工业大学 ， 化工过程机械， 2002， 硕士

【摘要】 本文首次对安装有弹簧插入物的竖管降膜蒸发的传热性能进行了实验研究，并与光管的传热性能进行了比较。通过大量的实验和对各种因素的综合分析，运用双机理传热模型，得到光管和安装有弹簧插入物的竖管降膜蒸发传热管液膜侧传热系数的计算式。实验表明，传热系数和液膜雷诺数、传热温差、料液物性参数利弹簧插入物的结构参数有关，实验条件下，安装有弹簧插入物的竖管降膜蒸发液膜侧的传热系数比光管的传热系数可高达25％左右，但某些结构参数的弹簧插入物会造成传热的恶化。通过弹簧插入物的各个参数对传热性能的影响分析，认为弹簧插入物对竖管降膜蒸发传热强化的机理主要是弹簧的振动加强了液膜的湍动，减薄了层流内层，从而强化了对流传热分量，但对沸腾传热分量没有影响。更多还原

【Abstract】 The heat transfer in vertical tube falling film evaporator equipped with spring inserts is investigated the first time. All kinds of influence factors are analyzed after a larger number of experiments. Exerting the model of two mechanism heat transfer , the formulation for heat transfer coefficient of liquid film which in smooth tube and equipped with spring inserts is given in this paper. Heat transfer coefficient is presented which not only has relation to Reynolds number, temperature difference, liquid characteristic, but also is greatly influenced by structure parameter of the spring inserts. Experiments indicate the heat transfer coefficient of tubes equipped with spring inserts is 25% higher than smooth tube. Heat transfer will worsen if structure parameters of the spring inserts are not fit. The paper think that the mechanism of heat transfer enhances of the spring inserts is the laminar flow lining is thinner because of librating of the spring inserts, accordingly the part of convection is enhanced. But the part of boil is not influenced.更多还原