摘要
甲烷水合物是由甲烷分子和水分子组成的清洁能源,维持水合物稳定存在的温度、压力条件称为水合物的相平衡。毛细压力影响着水合物的相平衡条件,尤其是相平衡压力。本文对已有的相平衡压力模型进行改进,并结合已有的水合物分解模型,提出了新的水合物分解模型。应用提出的模型对实验研究进行了数值模拟,数值模拟和实验研究结果的一致性较好,证明了所提模型的可靠性。明确了探究微孔隙内甲烷水合物分解时考虑水合物和水之间毛细压力的必要性。利用提出的模型进一步明确了甲烷生成速率、各相分布、温度分布、相平衡压力分布等的演变。研究结果表明,水合物的分解模型中应该考虑水合物和水之间的毛细压力,因为它严重影响着水合物分解模型的准确性。特别地,当忽略水合物和水之间的毛细压力时得到的累计产气量、甲烷生成速率值偏小。毛细压力、水合物的分解吸热和相间传热的耦合作用影响着相平衡压力的分布、甲烷生成速率的大小、各相的分布、温度的分布乃至相平衡压力的分布。毛细压力促使水合物的相平衡压力升高、水合物分解驱动力增大、促进了水合物的分解。所提出模型可为完善水合物分解模型提供理论基础。
Methane hydrate,composed of methane molecules and water molecules,represent a clean energy source.The maintenance of hydrate stability under specific temperature and pressure conditions is referred to as the phase equilibrium of hydrate.Capillary pressure significantly infuences the phase equilibrium conditions of hydrate,particularly the equilibrium pressure.This study improves existing phase equilibrium pressure models and proposes a novel hydrate decomposition model,incorporating existing hydrate decomposition models.The proposed model is validated through numerical simulations of experimental studies,demonstrating good consistency between numerical simulations and experimental results,thus verifying the reliability of the proposed model.It distinctly highlights the necessity of considering capillary pressure between hydrate and water when investigating methane hydrate decomposition within micropores.The proposed model further elucidates the evolution of methane generation rate,phase distributions,temperature distributions,and equilibrium pressure distributions.The research findings underscore the importance of incorporating capillary pressure between hydrate and water into hydrate decomposition models,as it significantly affects their accuracy.Specifically,neglecting capillary pressure between hydrate and water leads to underestimated cumulative gas production and methane generation rates.The coupling effect of capillary pressure,hydrate decomposition endothermicity,and inter-phase heat transfer influences the distribution of equilibrium pressure,methane generation rate,phase distributions,temperature distributions,and ultimately,the distribution of equilibrium pressure.Capillary pressure promotes an increase in the phase equilibrium pressure of hydrate,enhances the driving force for hydrate decomposition,and facilitates hydrate decomposition.The proposed model contributes to the theoretical foundation for enhancing hydrate decomposition models.
作者
王新
刘宏伟
梁冰
杨新乐
王芳
孙维吉
李维仲
宋永臣
WANG Xin;LIU Hongwei;LIANG Bing;YANG Xinle;WANG Fang;SUN Weiji;LI Weizhong;SONG Yongchen(School of Mechanical Engineering,Liaoning Technical University,Fuxin 123000,China;Post-doctoral Research Stations of Mechanics,Liaoning Technical University,Fuxin 123000,China;School of Mechanics&Engineering,Liaoning Technical University,Fuxin 123000,China;Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology,Dalian 116024,China)
出处
《工程热物理学报》
北大核心
2025年第6期1931-1941,共11页
Journal of Engineering Thermophysics
基金
国家自然科学基金面上项目(No.52074143,No.51776031,No.51774165)
辽宁省自然科学基金(No.2022-MS-398)
辽宁省教育厅科研项目(No.LJKMZ20220685,No.JYTMS20230803)
辽宁省自然资源厅(No.1638920994698)。
关键词
毛细压力
相平衡模型
传质限制
孔隙尺度
甲烷水合物分解
capillary pressure
equilibrium model
mass transfer limitation
pore-scale
methane hydrate dissociation
