TY  - EJOU
AU  - He, Huaiyin 
AU  - Zou, Longqing 
AU  - Li, Yanchao 
AU  - Wang, Yixuan 
AU  - Li, Junxiang 
AU  - Wen, Huan 
AU  - Chang, Bei 
AU  - Liu, Lijun 

TI  - Simulation Method and Feature Analysis of Shutdown Pressure Evolution During Multi-Cluster Fracturing Stimulation
T2  - Energy Engineering

PY  - 2024
VL  - 121
IS  - 1
SN  - 1546-0118

AB  - 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 of characteristics. Based on this method, the impacts of fracture half-length, fracture height, opened cluster and perforation number, and filtration coefficient on the evolution of shutdown pressure are analyzed. The results indicate that a larger fracture half-length may hasten the decay of shutdown pressure, while a larger fracture height can slow down the decay of shutdown pressure. A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure. A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown pressure. The simulation method of shutdown pressure, as well as the analysis results, has important implications for the interpretation of hydraulic fracture parameters.
KW  - Multistage multi-cluster hydraulic fracturing; pump shutdown pressure; feature analysis; numerical simulation

DO  - 10.32604/ee.2023.041010