Numerical Modeling of the Conductivity of the Particle Monolayer with Reduced Size

Abstract EN

Fractures filled with a proppant monolayer play an important role in the hydraulic fracture network.

Predicting the conductivity of these fractures is the basis of fracture network optimization.

However, little attention has been paid to the conductivity of the proppant monolayer.

The change of conductivity under various conditions is currently not fully understood.

Therefore, in this paper, the conductivity variation under different conditions are simulated.

The reduction of particle size was calculated by existing analytical models.

The permeability variation was calculated through computational fluid dynamics (CFD) combined with COMSOL Multiphysics.

The controlling factors of conductivity under a proppant monolayer were identified.

Simulation results indicate that elastic parameters, closure pressure, and proppant distribution have significant influence on conductivity, while creep parameters, such as rock viscosity and time, have limited influence on conductivity.

Moreover, the changes in permeability, porosity, and tortuosity with variation of embedment were analyzed.

Results indicated that with an increase in embedment, the permeability and porosity decrease as expected.

The main reduction (nearly half) emerges in the first 20% of proppant embedment.

Furthermore, the permeability of a single particle deviates largely from the prediction of Carman-Kozeny (CK) equation.

The tortuosity of proppant particle increases with a decrease in particle size due to embedment.

A modification of the Carman-Kozeny equation is proposed to address this influence.