Zhengyang Zhang^1,2, Jing Sun^1,2,*, Xin Shi³, Dehua Liu^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.3, pp. 509-527, 2025, DOI:10.32604/fdmp.2025.060393 - 01 April 2025

Abstract High saturation pressure reservoirs experience rapid pressure decline during exploitation, leading to significant changes in crude oil phase behavior and a continuous increase in viscosity after degassing, which adversely affects oil recovery. This challenge is particularly acute in tight sandstone reservoirs. To optimize the development strategy for such reservoirs, a series of experiments were conducted using core samples from a high saturation tight sandstone reservoir in the JS oilfield. Gas-dissolved crude oil was prepared by mixing wellhead oil and gas samples, enabling the identification of the critical point where viscosity changes as pressure decreases. Oil-water… More >

Min Feng^*, Long Wang, Lei Sun, Bo Yang, Wei Wang, Jianning Luo, Yan Wang, Ping Liu

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.3, pp. 573-587, 2025, DOI:10.32604/fdmp.2024.056421 - 01 April 2025

Abstract This study sheds light on how pore structure characteristics and varying dynamic pressure conditions influence the permeability of tight sandstone reservoirs, with a particular focus on the Paleozoic reservoirs in the Qingshimao Gas Field. Using CT scans of natural core samples, a three-dimensional digital core was constructed. The maximum ball method was applied to extract a related pore network model, and the pore structure characteristics of the core samples, such as pore radius, throat radius, pore volume, and coordination number, were quantitatively evaluated. The analysis revealed a normally distributed pore radius, suggesting a high degree… More >

Yan Liu¹, Tianli Sun², Bencheng Wang^1,*, Yan Feng²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.6, pp. 1165-1180, 2024, DOI:10.32604/fdmp.2023.041852 - 27 June 2024

Abstract A numerical model of hydraulic fracture propagation is introduced for a representative reservoir (Yuanba continental tight sandstone gas reservoir in Northeast Sichuan). Different parameters are considered, i.e., the interlayer stress difference, the fracturing discharge rate and the fracturing fluid viscosity. The results show that these factors affect the gas and water production by influencing the fracture size. The interlayer stress difference can effectively control the fracture height. The greater the stress difference, the smaller the dimensionless reconstruction volume of the reservoir, while the flowback rate and gas production are lower. A large displacement fracturing construction More >

Fang Li^1,*, Juan Wu¹, Haiyong Yi², Lihong Wu², Lingyun Du¹, Yuan Zeng¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 1015-1030, 2024, DOI:10.32604/fdmp.2023.043256 - 07 June 2024

Abstract Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors, such as strong reservoir heterogeneity and seepage mechanisms. In this study, the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments. On the basis of these experiments, a numerical simulation model (based on the special seepage mechanism) and an inverse dynamic reserve algorithm (with different equivalent drainage areas) were developed. The well spacing ranges of Classes I, II, and III wells in the Q gas More > Graphic Abstract

Zhengrong Chen^*, Mao Jiang, Chuanzhi Ai, Jianshu Wu, Xin Xie

Energy Engineering, Vol.121, No.6, pp. 1657-1669, 2024, DOI:10.32604/ee.2024.030222 - 21 May 2024

Abstract Based on the actual data collected from the tight sandstone development zone, correlation analysis using the Spearman method was conducted to determine the main factors influencing the gas production rate of tight sandstone fracturing. An integrated model combining geological engineering and numerical simulation of fracture propagation and production was completed. Based on data analysis, the hydraulic fracture parameters were optimized to develop a differentiated fracturing treatment adjustment plan. The results indicate that the influence of geological and engineering factors in the X1 and X2 development zones in the study area differs significantly. Therefore, it is… More >

Decheng Li¹, Yan Zhang², Dongdong Ma², Haozhe Geng¹, Yu Wu^1,2,*

Energy Engineering, Vol.120, No.11, pp. 2503-2516, 2023, DOI:10.32604/ee.2023.041803 - 31 October 2023

Abstract The fracturing process of sandstone is inherently complex due to its loose internal structure and deformation adaptability. Liquid nitrogen pre-injection has emerged as a promising approach to damage reservoir rocks, effectively reducing fracture pressure and establishing intricate fracture networks, thus offering a potential solution for reservoir reconstruction. To unravel the fundamental mechanisms governing sandstone fracturing behaviors following liquid nitrogen pre-injection, sandstone fracturing experiments were conducted under varying durations of liquid nitrogen injection, rock temperature, and in-situ stress conditions. The experiments showcased the evolution of injection pressure and fracture characteristics under different testing conditions, complemented by… More >

Jingjing Ping^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.08787

Abstract In the process of tight oil reservoir development, there are a lot of spontaneous imbibition phenomena which are beneficial to achieving the purpose of enhancing oil recovery. It is of great significance to study the law of spontaneous imbibition of oil and water at the pore scale of tight sandstone. In this paper, we study the law of spontaneous imbibition at the pore scale of tight sandstone by combining theoretical research and numerical simulation. Based on the fractal theory and the capillary bundle model, we establish a mathematical model of spontaneous imbibition in porous media More >

Dongsheng Li, Chunsheng Li^*, Kejia Zhang, Tao Liu, Fang Liu, Jingsong Yin, Mingyue Liao

Computer Systems Science and Engineering, Vol.47, No.1, pp. 1209-1231, 2023, DOI:10.32604/csse.2023.034395 - 26 May 2023

Abstract Intelligent identification of sandstone slice images using deep learning technology is the development trend of mineral identification, and accurate mineral particle segmentation is the most critical step for intelligent identification. A typical identification model requires many training samples to learn as many distinguishable features as possible. However, limited by the difficulty of data acquisition, the high cost of labeling, and privacy protection, this has led to a sparse sample number and cannot meet the training requirements of deep learning image identification models. In order to increase the number of samples and improve the training effect… More >

Jian Yang, Xiaoli Li^*, Hui Wang, Kaiqiang Geng

Journal of Renewable Materials, Vol.9, No.12, pp. 2241-2260, 2021, DOI:10.32604/jrm.2021.015565 - 22 June 2021

Abstract In the present study, in order to investigate the effects of fly ash on the structural evolution and strength damage mechanism of Pisha-sandstone cement soil, unconfined compressive strength tests of Pisha-sandstone cement soil with different fly ash content levels and various ages were carried out. The apparent morphology, microstructures, and chemical compositions of the samples were observed and analyzed using ultra-depth three-dimensional microscopy, scanning electron microscopy, and XRD methods. The results revealed that the unconfined compressive strength levels of Pisha-sandstone cement soil samples displayed increasing trends with the increases in fly ash content and age.… More > Graphic Abstract

Yong Wang, Yongyan Wang^*, Nan Qin, Sa Huang, Le Chang, Shunzheng Hou

Computer Systems Science and Engineering, Vol.39, No.1, pp. 121-131, 2021, DOI:10.32604/csse.2021.014464 - 10 June 2021

Abstract The work presented in this paper was conducted to quantify the relationship between the pore characteristics and mechanical properties of white sandstone. The study include tests carried out under the coupling effects of chemical corrosion, temperature, nuclear magnetic resonance, and mechanical tests. Computer fractal theory was employed to describe and quantify the characteristics of the growth of pores in white sandstone under the same coupling effect. A custom developed program code, in the MATLAB software platform, was used for calculating the growths of the pores in white sandstone when subjected to coupling effects. The correlation… More >