Investigation on the Condensation Heat Transfer Augmentation by Large Porosity Tube Inserts
By analyzing and comparing several types of enhancement of heat transfer measures used presently in condenser, a new method of augmentation condensation heat transfer is presented in this paper, that is, tube inserts with porous body of large porosity---twined coil. And the theoretical analysis and experimental investigation are carried out. The results show that it can make the fluids perform complicated three-dimensions mixed flow, make the heat flux appear “sudden” jump at lower temperature difference, make the flow go into turbulence ahead of time. The heat flux enhancement ratio increases by 3-4 times. If compared with other inserts, twined coil insert not only has better heat transfer enhancement performance, but also produces very small pressure drop, so it is an ideal and high efficiency energy saving technology. In the view of its application prospect, the feasibility of twined coil inserts applied to solar heat pump system is analyzed.
Yongguang Li, Yong Li and Weiguo Pan
J. L. Yang "Investigation on the Condensation Heat Transfer Augmentation by Large Porosity Tube Inserts", Advanced Materials Research, Vols. 608-609, pp. 1186-1189, 2013