摘要
在超临界甲烷及含氢甲烷的冷却换热研究中,由于其截面上温度的不均匀性导致物性的不均匀,从而影响其流动及换热,这些现象在实验中很难发现,计算机数值模拟为此提供给了便利。文中应用标准k-ε湍流模型对超临界气体在水平圆管内的冷却传热进行了数值模拟,研究了质量通量、热流密度、入口压力以及氢气含量对传热系数的影响。结果表明,换热系数随质量通量的增大而增大,随热流密度变化不明显,随入口压力的增大而减小,氢气含量增大时对流换热系数的峰值往低温方向移动。
In the research of cooling heat transfer to supercritical methane and methane/hydrogen mixture, unevenness of cross - sectional temperature leads to varying properties, which thus affects the flowing characteristics and heat transfer perform- ance. The phenomenon is difficult to observe in experiments, while numerical simulations using computers facilitate the investiga- tion. In this paper, numerical simulation of cooling heat transfer to supercritical gas with standard k - ε turbulent model in a hori- zontal circular tube was presented. Influences of mass flux, heat flux, inlet pressure and percentages of hydrogen on heat transfer coefficient were studied. The result showed that heat transfer coefficient increased with the increase of mass flux and the decrease of inlet pressure. The maximum of heat transfer coefficient occured at lower temperature for the higher hydrogen composition.
出处
《低温与超导》
CAS
北大核心
2014年第4期12-16,共5页
Cryogenics and Superconductivity
基金
国家高技术研究发展计划(863计划)资助项目(2009AA050905)
关键词
超临界
甲烷/氢混合物
冷却换热
水平圆管
数值模拟
Supercritical, Methane/hydrogen mixture, Cooling heat transfer, Horizontal circular tube, Numerical simulation
