摘要
通过对管内对流换热过程的灯用传递分析,提出用强化前后的传灯用Nu或传灯用量差ΔNue或ΔE作为强化传热性能评价指标。以工程上常用的螺旋槽管为例,讨论了Re、量纲1热通量、不同结构参数等对强化管传灯用性能的影响。分析结果表明,对于所选螺纹管结构参数,ΔNue随Re增加而增大;随量纲1热通量、量纲1长度的增加而递减。算式可有效评价强化管传灯用效果,以便选取最佳结构参数。
Based on the exergy transfer performance analysis of forced convective heat transfer through a duct with constant heat flux, an exergy transfer performance criterion △Nu. or △E, which is defined as the difference of exergy-transfer Nusselt number or exergy transfer rate before and after enhanced heat transfer, was proposed. By reference to spirally grooved tube, the effect of Reynolds number, structure parameters and non-dimensional parameter Nq on the exergy transfer process was discussed. The results show that the difference of exergy-transfer Nusselt number increases with the increase of Reynolds number, and decreases with the increase of Nq and non-dimensional parameter NL for the spirally grooved tube. A effective approach for exergy transfer performance evaluation and the optimal choice of enhanced heat transfer tube were presented in this paper.
出处
《热科学与技术》
CAS
CSCD
2006年第2期133-138,共6页
Journal of Thermal Science and Technology
关键词
强化传热
(火用)传递
性能评价
恒热流
enhanced heat transfer
exergy transfer
performance evaluation
constant heat flux
