New Insights on Acid Etched Fracturing Conductivity

Abstract:

Successful acid fracturing stimulation in carbonate reservoirs largely depends on the acid etched fracture conductivity. However, accurate prediction of this parameter is difficult due to the lack of knowledge for delicately charactering rough fracture surface. To push the limitation of the current situation, an advanced mathematical model is proposed based on the fractal theory and previous models. Matlab software is employed for generating rough surfaces with two variables, standard difference and fractal dimension. A partial differential equation is built to describe the fluid flow between two random fractal surfaces and finite element method is chosen to do simulation job. Comparative analysis of the flow ability between fractal surfaces and parallel plates is clarified at the final. The results show that fracture widths have the most influence on the conductivity, followed by fracture surface asperities. Moreover, fractal dimension and standard deviation, can also affect the fluid flow ability.

• Periodical: Advanced Materials Research (Volumes 807-809)
• Pages: 2762-2768
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.807-809.2762
• Online since: September 2013
• Authors: Xiao Gang Li, Yi Ting Wang, Zhao Zhong Yang
• Keywords: Acid Fracturing, Fractal, Fracturing Conductivity, Prediction Model

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