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论文类型：期刊论文

发表时间：2016-05-02

发表刊物：DESALINATION AND WATER TREATMENT

收录刊物：SCIE、Scopus

卷号：57

期号：21

页面范围：9993-10002

ISSN号：1944-3994

关键字：Tube arrangement; Seawater; Overall heat transfer coefficient; Horizontal-tube falling film; Desalination

摘要：In this paper, two sets of experimental devices have been established for studying the falling film evaporation outside a horizontal tube and condensation inside a horizontal tube, with three different tube arrangements and seawater as the experimental fluid. The rules of the overall heat transfer coefficient (K) are determined by changing saturation temperature (T), Reynolds number (Re), total temperature difference (Delta T), inlet steam velocity (v(s)), and vapor quality (x). Experimental results indicate that the overall heat transfer coefficient of the rotated square arrangement (K-rs) is higher than that of the triangular arrangement (K-t), and the square one (K-s) is the lowest with less impact on Re, T, Delta T, v(s), or x changing. With Re increasing, the K increases first and then declines, especially when Re>Re-cr, K-rs and K-t are almost the same. The increment of T and Delta T leads to the decreasing of the K, while v(s) has little effect on the K. The growth of x contributes a lot to the increment of the K. In the evaporator, the vapor quality contributes a lot in the horizontal direction, while Re is more influential in the vertical direction.