水合物热物理特性研究

发布时间：2018-06-17 09:05

  本文选题：水合物 + 热物性　； 参考：《中国石油大学(华东)》2015年硕士论文

【摘要】：目前,天然气水合物热物性参数的测量一般是基于时域信号测量。基于频域信号测量原理,研发的3ω独立探头大大拓展了该方法的应用范围。本文基于丝状独立探头和膜状独立探头,首先在低温高压下合成天然气水合物和二氧化碳水合物,然后利用3ω法测量水合物热导率、热扩散率、探头和水合物间界面热阻。在理论分析上,分析独立探头结构尺寸对测量结果的影响。对于Pt丝线热源传感器主要是Pt丝端部效应,热容效应和Pt丝长径比对测量结果的影响。对于膜状线热源传感器,分析镍带线宽和薄膜厚度对理论模型线热源近似程度和薄膜内二维热扩散效应的影响。在实验上,利用Pt丝线热源传感器测量跨临界CO_2的热导率和热扩散率。分析了跨临界状态下CO_2的热导率随温度、压力的变化关系。利用膜状线热源独立探头测量了-20℃~-3℃温度范围内甲烷水合物的热导率和热扩散率,与国内外学者的测量结果进行了比较。同时测量分析测试结构的界面热阻在温度范围内的变化。本文还分别利用膜状线热源传感器和Pt丝线热源传感器对比测量了CO_2水合物的热导率和热扩散率,验证了两种方法的一致性。利用分子动力学方法模拟了甲烷水合物的热导率,并分析了分子间作用力对热导率的影响。比较了模拟结果和实验结果的差异,同时验证实验数据的可行性。
[Abstract]:At present, the measurement of gas hydrate thermal properties is usually based on time domain signal measurement. Based on the principle of signal measurement in frequency domain, the developed 3 蠅 independent probe greatly expands the application range of this method. In this paper, gas hydrate and carbon dioxide hydrate are synthesized at low temperature and high pressure based on filamentary and membrane independent probes. Then the thermal conductivity, thermal diffusivity and interfacial thermal resistance between probe and hydrate are measured by 3 蠅 method. In the theoretical analysis, the influence of the structure size of the independent probe on the measurement results is analyzed. For Pt wire heat source sensor, it is mainly the end effect of Pt wire, the effect of heat capacity and the influence of length to diameter ratio of Pt wire. For the film linear heat source sensor, the influence of the wire width and film thickness on the approximation of the linear heat source in the theoretical model and the two-dimensional thermal diffusion effect in the film are analyzed. The thermal conductivity and thermal diffusivity of transcritical COs _ 2 were measured by Pt wire heat source sensor. The relationship between the thermal conductivity of COSP _ 2 and the temperature and pressure is analyzed in the transcritical state. The thermal conductivity and thermal diffusivity of methane hydrate in the temperature range of -20 鈩，

本文编号：2030495