考虑主-客体分子耦合作用的天然气水合物微观导热机理研究

传热是控制天然气水合物分解进程、制约产气效率的关键因素，探究天然气水合物的导热规律对优化天然气水合物开采方法具有重要意义。但是，由于天然气水合物稳定存在的苛刻条件和传统热物性测量技术的局限，天然气水合物导热规律的研究还比较匮乏。本项目以此为研究背景，探究天然气水合物的主-客体分子耦合机制和微观导热机理。利用飞秒激光抽运探测时域热反射系统实现天然气水合物微观导热规律的原位、非接触研究，获取天然气水合物导热规律对温度、压力、客体分子和笼子占比等的响应特征；利用拉曼光谱仪测试天然气水合物中客体分子的分布特征，获取主-客体分子的耦合作用机制，探明其对天然气水合物导热规律的影响；结合晶格动力学理论和分子动力学理论，研究天然气水合物内部声子输运机制，揭示天然气水合物晶体的微观导热机理。本项目旨在阐明天然气水合物导热规律，完善天然气水合物导热理论，为我国天然气水合物资源的高效开发提供理论支撑。

Heat transfer, which controls the hydrate dissociation progress and restricts the gas production efficiency, is a critical factor for natural gas hydrate exploitation. Investigating the thermal conduction characteristic of natural gas hydrate crystals is vital to optimize the mining method of natural gas hydrate resources. However, the database for this research is still deficient due to the rigorous stable conditions for natural gas hydrate and the limitation of traditional thermophysical measurement technique. Under above background, this project aims to explore the mechanisms of guest-host coupling and the characteristics of heat conduction in natural gas hydrates. The in-situ noncontact measurement will be conducted by using time-domain thermoreflectance system, and the effects of temperature, pressure, guest molecular, and cage occupancy on heat conduction will be also investigated. The distribution of guest molecules in natural gas hydrae will be determined by Raman spectroscopy, and the guest-host coupling mechanisms will be analyzed to reveal the thermal conduction mechanisms in natural gas hydrate. More accurate theoretical calculations based on lattice dynamics theory and molecular dynamics theory are required to understand the phonon transport mechanism and reveal the heat conduction behavior. In summary, this project aims to clarify the thermal conduction mechanism in natural gas hydrate by combining the experimental and theoretical research, and finally provide theoretical support for the high-efficient exploitation of natural gas hydrate resources.