海洋条件下印刷电路板式换热器多通道内超临界液化天然气瞬态分配特性分析  

Analysis on the Transient Flow Distribution Characteristics of Supercritical Liquified Natural Gas in Printed Circuit Heat Exchanger under Sloshing Conditions

作　　者：刘佳伦 唐凌虹 潘杰[2] 林金鹏 李会雄[3] LIU Jia-lun;TANG Ling-hong;PAN Jie;LIN Jin-peng;LI Hui-xiong(School of New Energy,Xi'an Shiyou University,Xi'an 710065,China;School of Petroleum Engineering,Xi'an Shiyou University,Xi'an 710065,China;State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安石油大学新能源学院,西安710065 [2]西安石油大学石油工程学院,西安710065 [3]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《科学技术与工程》2023年第13期5547-5558,共12页Science Technology and Engineering

基　　金：国家自然科学基金联合基金(U20B2036);陕西省自然科学基础研究计划(2022JQ-542);陕西省科学技术协会青年人才托举计划(20210404);热能动力技术重点实验室开放基金(TPL2020B02)。

摘　　要：印刷电路板式换热器(printed circuit heat exchanger,PCHE)是海上液化天然气(liquified natural gas,LNG)浮式储存和再气化装置的核心部件。在海洋条件下,其内部微细多通道间的流量分配特性复杂多变,易急剧恶化,严重影响气化效率和运行安全。通过UDF程序分别引入晃荡导致的周期性变化的附加惯性力及LNG物性计算关联式,构建适用于PCHE内超临界LNG流动与传热的三维非稳态模型,并开展了数值研究。结果表明,相比于初始稳态条件,晃荡过程中PCHE各通道内超临界LNG的流量及温度等参数随之发生周期性的震荡,而且工质分配的均匀性明显恶化,各通道间流量、温度分布的相对标准偏差均显著高于初始稳态值,最高甚至达到初始稳态值的3倍以上;晃荡振幅及晃荡频率越大,PCHE各通道间工质的流量分配及温度分布越不均匀;相比于在垂直于通道内工质流动方向上施加晃荡作用力,当在工质流动方向上施加晃荡作用力时,晃荡作用引发的工质分配恶化现象明显较为微弱,通道内参数的震荡幅度明显降低。Printed circuit heat exchanger(PCHE)is the core component of LNG floating storage and regasification unit(FSRU)at offshore conditions.The flow distribution among the small mini-channels becomes more complex and changeable,and it is prone to rapid deterioration under sloshing conditions.This seriously affects the regasification efficiency and operational safety of FSRU.In this regard,a three-dimensional mathematical model suitable for analyzing flow and heat transfer of supercritical LNG in PCHE under sloshing conditions was constructed,introducing the additional periodic inertial force caused by sloshing and calculation correlation of LNG multi-component physical properties through UDF.Then the related numerical research was carried out and the following conclusions were obtained.The flow rate and temperature of supercritical LNG in each channel of PCHE periodically oscillate,and the uniformity of the working fluid distribution was obviously deteriorated when inducing the sloshing condition.The relative standard deviations of the flow rate and temperature distribution among channels during the sloshing process were significantly higher than that at the initial steady value,and the max value even reaches more than 3 times the initial steady state value.The larger the sloshing amplitude and the sloshing frequency,the more uneven the flow distribution and temperature distribution among channels of PCHE.When the sloshing is applied in the flow direction of the channel,the deterioration of the flow distribution caused by the sloshing effect is obviously weaker,and the oscillation amplitude of the parameters in the channel is obviously reduced,compared to the situation when the sloshing is applied in the direction vertical to flow direction of the channel.

关 键 词：浮式储存和再气化装置 印刷电路板式换热器 海洋晃荡条件 超临界LNG 瞬态流量分配 

分 类 号：TK121[动力工程及工程热物理—工程热物理]