低渗致密气藏开发动态物理模拟实验相似准则

Similarity criterion of the physical simulating experiment for the development performances of low-permeability tight gas reservoirs

低渗致密气藏地质条件复杂,普遍含有孔隙水,渗流规律不清,开发动态早期难以预测。根据低渗致密气藏地质与开发特征,筛选出影响气藏开发动态的主要影响因素,并依据π定理确定了气藏开发物理模拟实验相似准数,阐述了其物理意义;以鄂尔多斯盆地低渗气藏X井为例,根据相似性准则,开展了气藏开发物理模拟实验研究,并与X井生产动态进行对比。结果表明:应用所建相似准则进行气藏开发物理模拟可以较好地预测气藏开发动态,得出的相似准则合理;关键相似准数为动力相似、运动相似和含水饱和度相似。研究成果对于低渗致密气藏有效开发具有重要的理论指导意义。

Low permeability tight gas reservoirs are characterized by the complex geological condition, widespread pore water and unclear seepage law, so it is difficult to predict the development dynamics in the early stage. According to the geology and development characteristics of the low-permeability tight gas reservoir, the major influencing factors of the reservoir development performances were screened out, and moreover the similarity criterion numerals of the physical simulating experiment for the reservoir development were determined by π theorem and furthermore their significances were stated;taking Well X located in the low-permeability gas reservoir of Ordos Basin as an example, according to the similarity criterion, the experimental study of the physical simulation for the gas reservoir development was conducted, and moreover the contrast was engaged with the production performances of the well stated above. The results show that the gas-reservoir physical simulation with the help of the established similarity criterion can well predict the development performances of the gas reservoir and the rationality of the criterion has been proven as well;the key similarity criterion numerals are the drive similarity, motion similarity and water saturation similarity. The study results possess important guiding significances in the theory of the high-efficiency development of the low-permeability tight gas reservoir.