数字模拟研究温度对受孔介质中受限扩散的影响
Zhen Xie1, Lizhi Xiao2,1, Sihui Luo3
1State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing, 102249, China.
Magnetic resonance letters
|September 8, 2025
概括
温度显著影响核磁共振 (NMR) 扩散-横向放松 (D-T2) 光谱,这对于评估水库特性至关重要. 模拟显示了温度的温度.
科学领域:
- 地质物理和石化物理.
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 孔隙介质物理 孔隙介质物理
背景情况:
- 准确评估水库的物理性质依赖于了解温度对受限扩散的影响.
- 核磁共振 (NMR) 扩散-横向放松 (D-T2) 光谱是地下特征的一个关键技术.
- 在水库条件下的温度变化可以显著改变多孔结构内的扩散动态.
研究的目的:
- 为了研究温度对受限扩散和水分子在毛孔中的2D NMR D-T2光谱的影响.
- 模拟和分析在一系列温度范围内扩散系数和D-T2光谱的行为.
- 为了建立温度效应和岩石特性之间的定量关系,如孔径,多孔度和凝固指数.
主要方法:
- 使用随机步行模拟来建模受限扩散和2DNMR D-T2光谱.
- 分析一维 (1D) 限制扩散,观察随时间推移的扩散系数行为.
- 应用帕德插值方程来建模和解释模拟的D-T2光谱.
主要成果:
- 模拟的扩散系数随着扩散时间的衰减而衰减,达到平原,温度影响速率.
- 限制在大量扩散系数的比率在长扩散时间时稳定,不受温度的影响.
- 模拟的D-T2光谱随着温度的增加而上升,并与帕德插值预测保持一致.
结论:
- 温度对NMR D-T2光谱具有可量化的影响,与孔径,孔隙度和凝固指数直接相关.
- 帕德插值方程准确地描述了多孔岩石中D-T2光谱的温度依赖行为.
- 了解这些温度效应对于使用NMR技术精确评估水库属性至关重要.
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