Numerical simulation study on the effect of temperature on the restricted diffusion in porous media  

作　　者：Zhen Xie Lizhi Xiao Sihui Luo Guangzhi Liao 

机构地区：[1]College of Artificial Intelligence,China University of Petroleum,Bejing,102249,China [2]State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing,02249,China [3]College of Carbon Neutral Energy,China University of Petroleum,Beijing,102249,China

出　　处：《Magnetic Resonance Letters》2023年第2期118-126,I0003,共10页磁共振快报（英文）

基　　金：supported by“National Natural Science Foundation of China(Grant No.42204106)”。

摘　　要：It is of great significance to study how temperature affects the restricted diffusion in pores for an accurate evaluation of reservoir physical properties by using nuclear magnetic resonance(NMR)diffusion-transverse relaxation(D-T2)spectrum under reservoir temperature conditions.In this paper,we simulate the restricted diffusion and twodimensional(2D)NMR D-T2 spectra of water molecules at different temperatures using random-walk method.The one-dimensional(1D)restricted diffusion simulation results show that the diffusion coefficient in the pore at room temperature decays with the diffusion time and eventually reaches a plateau.Under the condition of long-time diffusion,the ratio of restricted diffusion coefficient to bulk diffusion coefficient at different temperatures tends to be the same constant.With the increase in temperature,the simulated D-T2 spectra also gradually move upward.The simulated D-T2 spectra at all temperatures are consistent with the Pade interpolation equation.In addition,the results calculated by Pade interpolation equation demonstrate that the degree of temperature influence on the D-T2 spectrum of rock is quantitatively related to the pore radius,porosity and cementation index.

关 键 词：D-T_(2)spectra TEMPERATURE Restricted diffusion Numerical simulation 

分 类 号：TE311[石油与天然气工程—油气田开发工程] O657.2[理学—分析化学]