强制通风空浴式翅片管送风方式优化  

Optimization of Air Supply Mode on Vaporization Performance of an Air-Based Cryogenic Finned Tube Under Forced Convection

作　　者：时国华[1] 赵岳天 王子昂 蒋可 SHI Guo-hua;ZHAO Yue-tian;WANG Zi-ang;JIANG Ke(School of Energy Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,China;China Electronic System Engineering No.2 Construction Co.,Ltd.,Wuxi 214151,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,保定071003 [2]中国电子系统工程建设第二有限公司,无锡214151

出　　处：《科学技术与工程》2024年第18期7653-7661,共9页Science Technology and Engineering

基　　金：国家自然科学基金(52276007);河北省重点研发计划(21374501D)。

摘　　要：基于FLUENT模拟研究底送顶排、顶送底排、侧送顶排、侧送底排4种送风方式对液化天然气(liquefied natural gas,LNG)空浴式翅片管气化性能的影响,采用Lee模型研究管内LNG的相变气化过程,结合管内流体温度变化分析单根翅片管气化性能受送风方式和送风速度的影响。结果表明:侧送风时翅片管周围出现低风速边界层,背风侧易形成低换热效率的尾流区;当送风速度由2.8 m/s增大到3.8 m/s和由3.8 m/s增大到4.8 m/s时,侧送底排方式下空气侧换热系数最大值分别增长3.92 W/(m^(2)·K)和2.16 W/(m^(2)·K);直送风时边界层分布均匀,最大推荐送风速度为3.2 m/s,顶送底排方式对翅片管气化性能的提升效果优于底送顶排方式;当其他条件相同时,侧送顶排为最佳送风方式;采用侧送顶排强制通风的空浴式气化器(ambient air vaporizer,AAV)气化性能显著优于自然通风AAV。The influence of different air supply modes on the vaporization performance of a finned tube in LNG(liquefied natural gas)ambient air vaporizer was investigated by the FLUENT software,and the distribution of air physical parameters around the tube on different air supply modes i.e.,the bottom air supply and top air exhaust mode,the top air supply and bottom air exhaust mode,the side-air supply and top air exhaust mode,and the side-air supply and bottom air exhaust mode were analyzed.The vaporization process of liquefied natural gas in the tube was investigated by using the Lee model.The effects of air supply mode and air inlet velocity on the vaporization capacity of the finned tube were analyzed by considering the variation of fluid temperature in the tube.The results indicate that the low wind speed boundary layer appears around the finned tubes,and a wake range with poor heat exchange efficiency is likely to be formed on the leeward side of the tube for side air-supply modes.When the air inlet velocity increases from 2.8 m/s to 3.8 m/s,and from 3.8 m/s to 4.8 m/s,the maximum heat transfer coefficients on the air side increase by 3.92 and 2.6 W/(m^(2)·K)respectively for the side-air supply and bottom air exhaust mode.The boundary layer distribution for the bottom air supply mode and the top air supply mode is uniform,and the maximum recommended air inlet velocity is 3.2 m/s because the heat transfer performance does not increase significantly with the rise on the air velocity.The vaporization performance of the finned tube on the top air supply mode is better than that on the bottom air supply mode.Among the four air supply modes,the side-air supply and top air exhaust mode is the best one to improve the heat transfer performance of the single finned tube.The forced-draft AAV(ambient air vaporizer)using the side-air supply and top air exhaust mode has a much better vaporization performance than the general AAV.

关 键 词：传热 液化天然气 送风方式 气化性能 空浴式气化器 

分 类 号：TK124[动力工程及工程热物理—工程热物理]