Effects of tube cross-sectional shapes on flow pattern, liquid film and heat transfer of n-pentane across tube bundles  

作　　者：Xuejing He Zhenlin Li Ji Wang Hai Yu 

机构地区：[1]College of Mechanical and Transportation Engineering,China University of Petroleum(Beijing),Beijing 102249,China

出　　处：《Chinese Journal of Chemical Engineering》2023年第8期16-25,共10页中国化学工程学报（英文版）

基　　金：supported by National Natural Science Foundation of China (52006242);National Natural Science Foundation of China (52192623);Science Foundation of China University of Petroleum,Beijing (ZX20200126);Science and technology program for strategic cooperation of CNPC–China University of Petroleum (ZLZX2020-05)。

摘　　要：The heat transfer of hydrocarbon refrigerant across tube bundles have been widely used in refrigeration.Three-dimensional simulation model using volume of fluid(VOF) was presented to study the effects of tube shapes on flow pattern, film thickness and heat transfer of n-pentane across tube bundles, including circle, ellipse-shaped, egg-shaped and cam-shaped tube bundles. Simulation results agree well with experimental data in the literature. The liquid film thickness of sheet flow and heat transfer for different tube shapes were obtained numerically. The flow pattern transition occurs lower vapor quality for ellipse-shaped tube than other tube shapes. For sheet flow, the liquid film on circle tube and ellipseshaped tube is symmetrically distributed along the circumferential direction. However, the liquid film on egg-shaped tube at circumferential angles(θ) = 15°–60° is thicker than θ = 135°–165°. The liquid film on cam tube at θ = 15°–60° is slightly thinner than θ = 135°–165°. The liquid film thickness varies from thinner to thicker for ellipse-shaped, cam-shaped, egg-shape and circle within θ = 15°–60°. The effect of tube shape is insignificant on thin liquid film thickness. Ellipse-shaped tube has largest heat transfer coefficient for sheet flow. In practical engineering, the tube shape could be designed as ellipse to promote heat transfer.

关 键 词：Tube shapes Flow pattern Liquid film thickness Heat transfer Two-phase flow 

分 类 号：TQ021[化学工程]