Lian Liu^1,2, Liang Li^1,2, Kebo Jiao^1,2,*, Junwei Fang^1,2, Yun Luo^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 975-987, 2024, DOI:10.32604/fdmp.2023.030109 - 07 June 2024

Abstract Ultra-deep reservoirs play an important role at present in fossil energy exploitation. Due to the related high temperature, high pressure, and high formation fracture pressure, however, methods for oil well stimulation do not produce satisfactory results when conventional fracturing fluids with a low pumping rate are used. In response to the above problem, a fracturing fluid with a density of 1.2~1.4 g/cm was developed by using Potassium formatted, hydroxypropyl guanidine gum and zirconium crosslinking agents. The fracturing fluid was tested and its ability to maintain a viscosity of 100 mPa.s over more than 60 min More >

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 >

Rui Zhang¹, Lixiang Wang^2,*, Jing Li^1,4, Chun Feng², Yiming Zhang^1,3,4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.2, pp. 2103-2129, 2024, DOI:10.32604/cmes.2024.049885 - 20 May 2024

Abstract Perforation is a pivotal technique employed to establish main flow channels within the reservoir formation at the outset of hydraulic fracturing operations. Optimizing perforation designs is critical for augmenting the efficacy of hydraulic fracturing and boosting oil or gas production. In this study, we employ a hybrid finite-discrete element method, known as the continuous–discontinuous element method (CDEM), to simulate the initiation of post-perforation hydraulic fractures and to derive enhanced design parameters. The model incorporates the four most prevalent perforation geometries, as delineated in an engineering technical report. Real-world perforations deviate from the ideal cylindrical shape, More >

Jean Aime Mono^1,2,*, Apollinaire Bouba³, Jean Daniel Ngoh⁴, Olivier Ulrich Igor Owono Amougou⁵, Françoise Martine Enyegue A Nyam⁶, Théophile Ndougsa Mbarga⁷

Revue Internationale de Géomatique, Vol.33, pp. 135-154, 2024, DOI:10.32604/rig.2024.049966 - 15 May 2024

Abstract This study focuses on the mapping of lineaments using remote sensing techniques and Geographic Information Systems. The aim is to carry out a statistical analysis of the lineaments in order to better understand the organization of fracturing in the Batie district, and to identify areas of high fracturing density and their relationship with the hydrographic network. The methodology implemented to achieve these objectives is based on the processing and analysis of Landsat 9 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) satellite imagery and Shuttle Radar Topography Mission (SRTM) data covering the study area. After essential pre-processing… More >

Diguang Gong¹, Junbin Chen¹, Cheng Cheng², Yuanyuan Kou^2,*

Energy Engineering, Vol.121, No.2, pp. 425-437, 2024, DOI:10.32604/ee.2023.030196 - 25 January 2024

Abstract Horizontal well-stimulation is the key to unconventional resource exploration and development. The development mode of the well plant helps increase the stimulated reservoir volume. Nevertheless, fracture interference between wells reduces the fracturing effect. Here, a 2D hydro-mechanical coupling model describing hydraulic fracture (HF) propagation is established with the extended finite element method, and the effects of several factors on HF propagation during multiple wells fracturing are analyzed. The results show that with an increase in elastic modulus, horizontal principal stress difference and injection fluid displacement, the total fracture area and the reservoir stimulation efficiency are More >

Lifeng Liu¹, Menghe Shi², Jianhui Wang³, Wendong Wang^2,*, Yuliang Su², Xinyu Zhuang²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 595-607, 2024, DOI:10.32604/fdmp.2023.041962 - 12 January 2024

Abstract Ultra-low permeability reservoirs are characterized by small pore throats and poor physical properties, which are at the root of well-known problems related to injection and production. In this study, a gas injection flooding approach is analyzed in the framework of numerical simulations. In particular, the sequence and timing of fracture channeling and the related impact on production are considered for horizontal wells with different fracture morphologies. Useful data and information are provided about the regulation of gas channeling and possible strategies to delay gas channeling and optimize the gas injection volume and fracture parameters. It More >

Hao Zhang¹, Yan Zhang^1,*, Wei Liu², Ximin Zhang³, Xiang Liu²

Energy Engineering, Vol.121, No.1, pp. 27-42, 2024, DOI:10.32604/ee.2023.041410 - 27 December 2023

Abstract The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale, which affects the fracturing effect. Accordingly, we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation, based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation. The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion. And a 15% concentration of hydrochloric acid can… More >

Huaiyin He¹, Longqing Zou¹, Yanchao Li¹, Yixuan Wang¹, Junxiang Li¹, Huan Wen¹, Bei Chang¹, Lijun Liu^2,*

Energy Engineering, Vol.121, No.1, pp. 111-123, 2024, DOI:10.32604/ee.2023.041010 - 27 December 2023

Abstract Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs, but the interpretation of hydraulic fracture parameters is challenging. The pressure signals after pump shutdown are influenced by hydraulic fractures, which can reflect the geometric features of hydraulic fracture. The shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective manner. In this paper, a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction, perforation friction and fluid loss in fractures. An efficient numerical simulation method is established by using the method… More >

Yongwei Duan, Zhaopeng Zhu, Hui He^*, Gaoliang Xuan, Xuemeng Yu

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 349-364, 2024, DOI:10.32604/fdmp.2023.042659 - 14 December 2023

Abstract The gas-water two-phase flow occurring as a result of fracturing fluid flowback phenomena is known to impact significantly the productivity of shale gas well. In this work, this two-phase flow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model (EDFM). This model assumes the region outside the stimulated reservoir volume (SRV) as a single-medium while the SRV region itself is described using a double-medium strategy which can account for the fluid exchange between the matrix and the micro-fractures. The shale gas adsorption, desorption, diffusion, gas slippage… More >

Yu Gao¹, Zhenqiang Xu^2,3,*, Kaixiang Shen^2,3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 179-192, 2024, DOI:10.32604/fdmp.2023.030499 - 08 November 2023

Abstract Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perforation tool. In this study, the flow behavior of the nozzle is simulated numerically in the framework of a SST k-ω turbulence model. The results show that the nozzle structure can significantly influence the jet performance and related cavitation effect. Through orthogonal experiments, the nozzle geometric parameters are optimized, and the following configuration is found accordingly: contraction angle 20°, contraction segment More >