Gang Wang, Shuxin Wang, Yixin Liu, Qiming Huang, Shengpeng Li, Shuliang Xie, Jinye Zheng, Jiuyuan Fan
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引用次数: 0
Abstract
The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal samples for experiments, and clean fracturing fluid samples were prepared using CTAB surfactant. A series of hydraulic fracturing tests were conducted with an in-house developed triaxial hydraulic fracturing simulator and the fracturing process was monitored with an acoustic emission instrument to analyze the influences of fracturing fluid viscosity and horizontal in-situ stress difference on coal fracture propagation. The results show that the number of branched fractures decreased, the fracture pattern became simpler, the fractures width increased obviously, and the distribution of AE event points was concentrated with the increase of the fracturing fluid viscosity or the horizontal in-situ stress difference. The acoustic emission energy decreases with the increase of fracturing fluid viscosity and increases with the increase of horizontal in situ stress difference. The low viscosity clean fracturing fluid has strong elasticity and is easy to be compressed into the tip of fractures, resulting in complex fractures. The high viscosity clean fracturing fluids are the opposite. Our experimental results provide a reference and scientific basis for the design and optimization of field hydraulic fracturing parameters.
期刊介绍:
The International Journal of Coal Science & Technology is a peer-reviewed open access journal that focuses on key topics of coal scientific research and mining development. It serves as a forum for scientists to present research findings and discuss challenging issues in the field.
The journal covers a range of topics including coal geology, geochemistry, geophysics, mineralogy, and petrology. It also covers coal mining theory, technology, and engineering, as well as coal processing, utilization, and conversion. Additionally, the journal explores coal mining environment and reclamation, along with related aspects.
The International Journal of Coal Science & Technology is published with China Coal Society, who also cover the publication costs. This means that authors do not need to pay an article-processing charge.