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论文类型：期刊论文

发表时间：2016-07-01

发表刊物：INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER

收录刊物：Scopus、EI、SCIE

卷号：75

页面范围：124-129

ISSN号：0735-1933

关键字：Heat transfer enhancement; Twisted tape; Dual-pipe heat exchanger

摘要：In this paper, an experimental research was carried out to study the heat transfer and friction factor characteristics in a tube with a new kind of twisted tape insert. Four twisted tapes with different lengths (2400, 1800, 1200 and 600 mm) were used in the experimental study. The experimental data revealed that Nusselt number caused by these four twisted tapes were 1.45-1.90, 1.23-1.55, 1.18-1.45 and 1.15-1.37 times of that for the plain tube, while the values for friction factor were 3.69-5.75, 2.30-4.48, 2.15-2.75 and 1.21-1.31. The performance evaluation criteria (PEC) for length ratio of 1.0, 0.75, 0.50 and 0.25 is 0.94-1.06, 0.82-0.94, 0.89-1.04 and 0.89-1.06, respectively. What's more, correlations for Nusselt number and friction factor were established in the paper. The predicted values calculated by correlations were in good agreement with experimental data, within 7% for Nusselt number and within 10% for friction factor. (C) 2016 Elsevier Ltd. All rights reserved.