Numerical Study On The Flow And Heat Transfer Characteristics Of Interrupted Annular Groove Fin With Different Groove Diameter

With the rapid development of technology and economy, the energy consumed by human beings is also increasing steadily. This has been caused a lot of pollution and environment problem, which bring huge negative pressure. At present, in china the main contradiction for the usage of the energy is that energy varieties of a single and low efficiency,so how to improve energy utilization efficiency and reduce emissions to the environment becomes more and more important. Heat Exchanger as the most widely used component in the energy exchange and utilization, improve its efficiency for the energy utilization rate has an important influence.Fin and tube heat exchanger as a kind of compact exchangers is widely used in the field of petrochemical, aerospace, automobile and metallurgical industry. For the application of fin and tube exchangers, its performance is mainly determined by the heat transfer capability of fin surface, namely the heat transfer coefficient of fin surface. In order to improve the heat transfer coefficient of fin surface, a variety of different structure styles of fin have been developed so far. Interrupted half annular groove fin(IHAGF), as a kind of typical heat exchanger fin surface, has its good comprehensive heat transfer and fluid characteristics. In this paper, the heat transfer and fluid flow characteristics in the channel formed by IHAGF with five different diameters and three grooves with different arc length are numerically investigated. The numerical results show that, when the fin spacing is constant, the average Nusselt number and the secondary flow intensity are all increase with increasing the diameter of the groove, the incensement is more obvious at high Reynolds number. Friction coefficient also increases with the increase of diameter of the annular groove. And at the same groove diameter and the fin spacing, Nusselt number and the friction factor increase when arc lengthen of the annular groove is large. By calculating the heat transfer performance factor JF,we obtain the theoretic optimal diameter and arc length of the annular groove and corresponding fin spacing for the structure studied in this paper. Finally, we employed the multivariate regression analysis method to get the correlations of Nusselt number and the friction coefficient regarding to the geometrical parameters and working parameters studied in this paper studied and the data published in the literature. These results can provide more data for the optimization design of two-row tube interrupted annular groove fin.