CO_2在-8~-12℃温度下水平管内冷凝过程的分析Study on Condensation of Carbon Dioxide inside a Horizontal Smooth Tube at -8~-12℃ Temperature
马一太,宁静红,李敏霞
MA Yi-tai; NING Jing-hong; LI Min-xia(Tianjin University;
摘要(Abstract):
通过对CO2在-8~-12℃温度下水平圆管内冷凝过程的局部换热系数和压降的计算,得出CO2冷凝过程中的局部换热系数和压降随CO2蒸汽干度的变化关系,同时得到水平管的管径、冷凝温度和CO2质量流率对局部换热系数和压降的影响情况,而水平管的直径对局部换热系数和压降影响较大。此研究对CO2制冷系统冷凝过程的实验研究及CO2冷凝换热器的设计提供了相应的理论依据。
Calculation data for local heat transfer coefficient and pressure drop with the quality of CO_2 obtained was presented in horizontal,round smooth tube at -8~-12℃ temperature. The effects result from tube diameter and condensation temperature ,as well as mass fluxes on local heat transfer coefficient and pressure drop are acquired. Yet the effects of tube diameter are larger than others.The theory basis for the experimental study of CO_2 condensation and the design of CO_2 condenser are provided.
关键词(KeyWords):
CO2;局部换热系数;压降;蒸汽干度
CO_2;local heat transfer coefficient; pressure drop; quality
基金项目(Foundation):
作者(Authors):
马一太,宁静红,李敏霞
MA Yi-tai; NING Jing-hong; LI Min-xia(Tianjin University;
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