توسط نوار پيچيده شده R-B4A افزايش انتقال حرارت در چگالنده يك سيكل تبريد با مبرد

Augmentation of Heat Transfer in the Condenser of a Refrigeration Cycle by Twisted Tape Inserts

In the present work, heat transfer augmentation during condensation of R-134a vapors inside horizontal twisted tapes inserted tubes has been investigated experimentally. Test condenser was a double pipe counter-flow water cooled heat exchanger which refrigerant flowed inside the internal tube, while water flowed in the annulus. Twisted tapes with different twisted ratios were used in full length of test condenser. It is found that the use of twisted tape increased the condensing heat transfer rates by as much as 43 percent above the plain tube values on a nominal area basis. Influence of a variety of parameters such as vapor quality and twisted tape geometry on the heat transfer augmentation was also investigated. An empirical correlation was developed to predict the enhanced heat transfer coefficients.