摘要
以描述缠绕管式换热器管程对流传热的Schmidt公式为基础,将内部流动传热的非平衡热力学模型相与Schmidt公式相结合,对缠绕管式换热器管程对流传热的非平衡热力学理论模型进行了理论研究;提出了传热熵产数(Ns,HX)和阻力熵产数(Ns,P)的概念;对缠绕管式换热器管程的Nu、ΔP、Ns,HX和Ns,P的变化规律进行了研究;结果显示,Nu随着Re的升高而升高,传热熵产数(Ns,HX)随着Re的升高而降低;ΔP和阻力熵产数(Ns,P)都随着Re的升高而增大;传热熵产数(Ns,HX)和阻力熵产数(Ns,P)能有效反映缠绕管式换热器管程对流传热过程的不可逆损失的变化规律,揭示了缠绕管式换热器管程对流传热的非平衡热力学原理。
A non-equilibrium thermodynamic model for coiled tubes was theoretically studied based on Schmidt correlation which was also correlated with non-equilibrium thermodynamic theory for internal flow.A heat transfer entropy number(Ns,HX)and a resistance entropy number(Ns,P)were proposed.Variation of Nu,ΔP,Ns,HX and Ns,P along with Re was investigated.The results show that Nu,ΔP and Ns,P increase with the increase of Re.However,Ns,HX decreases with the increase of Re.Ns,HX and Ns,P reflect the irreversible loss in the convection heat transfer process in coiled tubes,which also reveal the non-equilibrium thermodynamic mechanism of convection heat transfer in coiled-tube heat exchangers.
作者
韩勇
王学生
陈琴珠
张朝
袁宇阳
HAN Yong;WANG Xue-sheng;CHEN Qin-zhu;ZHANG Zhao;YUAN Yu-yang(Key Laboratory of Pressure System and Safety, Ministry of Education,East China University of Science and Technology, Shanghai 200237, China)
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2018年第6期1280-1287,共8页
Journal of Chemical Engineering of Chinese Universities
关键词
缠绕管
对流传热
非平衡热力学
熵产
熵产数
coiled tube
convection heat transfer
non-equilibrium thermodynamics
entropy
entropy number
