Constructing Sub-scale Surrogate Model for Proppant Settling in Inclined Fractures from Simulation Data with Multi-fidelity Neural Network

TL;DR

This paper develops a multi-fidelity neural network surrogate model for proppant settling in inclined fractures, significantly reducing computational costs while maintaining high accuracy, thereby improving large-scale hydraulic fracturing simulations.

Contribution

It introduces a multi-fidelity neural network approach to efficiently construct an accurate proppant settling surrogate model using both high- and low-fidelity data.

Findings

Reduces high-fidelity data requirement by 80%

Maintains less than 5% accuracy loss compared to high-fidelity models

Enables rapid and accurate proppant transport simulations

Abstract

Particle settling in inclined channels is an important phenomenon that occurs during hydraulic fracturing of shale gas production. Generally, in order to accurately simulate the large-scale (field-scale) proppant transport process, constructing a fast and accurate sub-scale proppant settling model, or surrogate model, becomes a critical issue, since mapping between physical parameters and proppant settling velocity is complex. Previously, particle settling has usually been investigated via high-fidelity experiments and meso-scale numerical simulations, both of which are time-consuming. In this work, a new method is proposed and utilized, i.e., the multi-fidelity neural network (MFNN), to construct a settling surrogate model, which could utilize both high-fidelity and low-fidelity (thus, less expensive) data. The results demonstrate that constructing the settling surrogate with the MFNN can reduce the need for high-fidelity data and thus computational cost by 80%, while the accuracy lost is less than 5% compared to a high-fidelity surrogate. Moreover, the investigated particle settling surrogate is applied in macro-scale proppant transport simulation, which shows that the settling model is significant to proppant transport and yields accurate results. This opens novel pathways for rapidly predicting proppant settling velocity in reservoir applications.