Reservoir Evaluation and Development ›› 2018, Vol. 8 ›› Issue (4): 36-41.

• Petroleum Engineering • Previous Articles     Next Articles

Multifactorial experiment of acid's fingering phenomenon in the multi-stage alternating injection of acid fracturing

Luo Zhifeng1,Yu Yang1,Zhao Liqiang1,Li Xiaogang1,Zhao Xingdong2   

  1. 1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China
    2. Engineering Technology Research Institute of Southwest Oil and Gas Company of CNPC, Chengdu, Sichuan 610000, China
  • Received:2017-10-10 Online:2018-08-26 Published:2018-11-28


The evolution characteristics and the final shape of acid viscosity fingering are influenced by many engineering and geological factors. So that, we used the visual experimental device to explore the change rules under the multifactor. Six factors were considered, those are the concentration of acid, the injection series, the temperature, the construction displacement, the viscosity ratio of the liquid, and the inclination of crack. The fractal dimension and multifractal spectrum width were used to describe the morphological of fingering. It is concluded that the influence degree of each factor on fractal dimension from high to low is in the order of: viscosity ratio, injection series, temperature, acid concentration, construction displacement, and crack inclination. The influence degree of each factor on the multifractal spectrum width from high to low is in the order of: viscosity ratio, crack inclination, construction displacement, acid concentration, injection series, and temperature. In order to achieve the viscosity fingering of acid fracturing, the viscosity ratio should be increased to the value between 100∶1 and 150∶1, the controlled injection series are at level 2 to level 3, and the designed acid dosage is about 0.3. Meanwhile, a large number of pre-liquid was injected to reduce the crack wall's temperature before the acid injection.

Key words: acid fracturing, acid's fingering, physical simulation, fractal dimension, multifractal spectrum width

CLC Number: 

  • TE319