Page 22 - 《真空与低温》2025年第4期
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第  31 卷    第  4 期                          真空与低温
                 2025 年 7 月                           Vacuum and Cryogenics                                437



                          填   料   润   湿   性  对    CH -C H -CO 流            动   传   热   影  响   的
                                                                      2
                                                       4
                                                               6
                                                           2
                                                 分   子   动  力   学   模   拟

                                                                  1*
                                                  刘俊明 ,林文胜 ,许婧煊            2
                                                         1
                                    (1. 上海交通大学制冷与低温工程研究所,上海 200240;
                                    2. 上海理工大学储能科学与工程研究所,上海 200093)


                     摘要:在精馏填料塔中,传热传质过程主要发生在填料区域,填料润湿性对流动传热有显著影响。通过分子
                  动力学模拟,研究了       CH 4 -C 2 H 6 -CO 2 三元流体在填料微小通道内的流动与传热过程,重点分析了不同填料表面润湿
                  性对流动与传热特性的影响。研究结果表明,填料表面润湿性显著影响通道内流体的温度分布、速度分布及分子
                  层结构。润湿性越强,通道壁面对流体的作用力越大,近壁面区域的分子分布更为集中,温度梯度减小,固液界面
                  处的温度阶跃和速度滑移量均有所降低,从而强化了通道内壁面与流体的热传导过程,但增大了流体阻力。研究
                  从微观分子层面揭示了润湿性对流动与传热过程的影响机理,为                     LNG  工业中优化低温精馏脱碳工艺提供了理论支持。
                     关键词:CH 4 -C 2 H 6 -CO 2 三元混合物;低温精馏;填料;润湿性;分子动力学模拟
                     中图分类号:TB69                      文献标志码:A       文章编号:1006−7086(2025)04−0437−08
                     DOI:10.12446/j.issn.1006-7086.2025.04.003

               The Effect of Packing Wettability on CH 4 -C 2 H 6 -CO 2  Flow and Heat Transfer: A Molecular Dynamics Study


                                                       1            1*           2
                                            LIU Junming ,LIN Wensheng ,XU Jingxuan
                      (1. Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai 200240,China;
                                         2. Institute of Energy Storage Science and Engineering,
                                University of Shanghai for Science and Technology,Shanghai 200093,China)


                     Abstract:In a distillation packed column,the process of heat and mass transfer primarily occur within the packing region,
                  where the wettability of the packing material significantly influences convective heat transfer. This study employs molecular
                  dynamics simulations to investigate the flow and heat transfer processes of a ternary fluid system consisting of methane,ethane,
                  and carbon dioxide within the microchannels of packing materials. The focus is on analyzing how different wettability charac-
                  teristics of the packing surfaces affect the flow and heat transfer properties of the fluid.By comparing the simulation results with
                  existing literature and standard data from the National Institute of Standards and Technology(NIST),the molecular interac-
                  tion potential suitable for the CH 4 -C 2 H 6 -CO 2  ternary system has been validated. The research results indicate that,influenced by
                  molecular mass and molecular interaction forces,the three types of molecules exhibit different therma diffusivities and thermal
                  conductivities,ranked from highest to lowest as CH 4 ,C 2 H 6 ,and CO 2 . The wettability of the packing surfaces has a profound
                  impact on the temperature distribution,velocity distribution,and molecular layering within the channel. Specifically,stronger
                  wettability leads to greater interaction forces between the fluid and the channel walls,resulting in a more concentrated molecular
                  distribution near the wall region. This concentration effect reduces the temperature gradient,as well as the hydrodynamic and
                  thermal slip at the solid-liquid interface,thereby enhancing the heat transfer process between the channel walls and the fluid.
                  However,this increased wettability also leads to higher fluid resistance. By revealing the underlying mechanisms through which
                  wettability influences flow and heat transfer at the microscopic molecular level, this research provides valuable theoretical
                  support for optimizing low-temperature distillation and decarbonization processes in the liquefied natural gas (LNG) industry.
                     Key words:CH 4 -C 2 H 6 -CO 2  ternary mixture;cryogenic distillation;packing;wettability;molecular dynamics simulation


              收稿日期:2024−11−21
              基金项目:国家自然科学基金(52276012)
              作者简介:刘俊明,硕士研究生。E-mail:ljm2333 hhh@sjtu.edu.cn
              通信作者:林文胜,博士,副教授,博士生导师。E-mail:linwsh@sjtu.edu.cn
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