基于热管强化传热的天然气水合物孔底冷冻取样器优化研究

Optimization research on natural gas hydrate hole-bottom freezing sampler based on the heat pipe enhanced heat transfer

摘要:

针对天然气水合物孔底冷冻取样器冷源利用率低的问题，本文提出基于热管强化传热的优化方案。搭建取样装置试验台，开展岩心冷冻室内试验，初步研究热管对储冷机构与冷冻机构间传热效果的优化作用。结合传热数值模拟，进一步分析热管在取样器中的作用，探讨在海洋水合物取心工况下，不同冷源初始温度和取心长度对冷冻机构冷冻效果的影响。结果表明，热管优化结构使岩心温度分布更均匀，冷源利用率提升31.59%，岩心冷冻速率提升42.21%。使用热管强化传热，增强了天然气水合物孔底冷冻取样器的冷冻效果，对推动孔底冷冻取样器的工程应用、打破国外对水合物取样技术的垄断具有积极的意义。

Abstract:

Aiming at the key technical bottleneck of low cold source utilization rate in natural gas hydrate hole-bottom freezing sampler， an optimization scheme using heat pipes to enhance heat transfer was proposed. A sampling device test bench was built to conduct indoor experiments on gas hydrate core freezing， and study the effect of heat pipes optimized heat transfer between the cold storage mechanism and the freezing mechanism. Combined with the numerical simulation of heat transfer， the role of heat pipes in the sampler was further analyzed to explore the effects of different initial temperatures of cold sources and core lengths on the freezing effect of the freezing mechanism under the working condition of marine hydrate coring. The research results show that optimizing the structure with the heat pipe makes the temperature distribution of the core more uniform， increases the cold source utilization rate by 31.59%， and the core freezing rate by 42.21%. The use of heat pipes to strengthen heat transfer enhances the freezing effect of the natural gas hydrate hole-bottom freezing sampler， which is of positive significance for promoting the engineering application of the hole-bottom freezing sampler and breaking the monopoly of foreign countries on hydrate sampling technology.