Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs

Nonuniform proppant distribution is fairly common in hydraulic fractures, and different closure behaviors of the propped and unpropped fractures have been observed in lots of physical experiments. However, the modeling of partially propped fracture closure is rarely performed, and its effect on gas...

Full description

Bibliographic Details
Main Authors: Xia Yan, Zhaoqin Huang, Qi Zhang, Dongyan Fan, Jun Yao
Format: Article
Language:English
Published: MDPI AG 2020-10-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/13/20/5339
_version_ 1827704350922768384
author Xia Yan
Zhaoqin Huang
Qi Zhang
Dongyan Fan
Jun Yao
author_facet Xia Yan
Zhaoqin Huang
Qi Zhang
Dongyan Fan
Jun Yao
author_sort Xia Yan
collection DOAJ
description Nonuniform proppant distribution is fairly common in hydraulic fractures, and different closure behaviors of the propped and unpropped fractures have been observed in lots of physical experiments. However, the modeling of partially propped fracture closure is rarely performed, and its effect on gas production is not well understood as a result of previous studies. In this paper, a fully coupled fluid flow and geomechanics model is developed to simulate partially propped fracture closure, and to examine its effect on gas production in fractured shale reservoirs. Specifically, an efficient hybrid model, which consists of a single porosity model, a multiple porosity model and the embedded discrete fracture model (EDFM), is adopted to model the hydro-mechanical coupling process in fractured shale reservoirs. In flow equations, the Klinkenberg effect is considered in gas apparent permeability, and adsorption/desorption is treated as an additional source term. In the geomechanical domain, the closure behaviors of propped and unpropped fractures are described through two different constitutive models. Then, a stabilized extended finite element method (XFEM) iterative formulation, which is based on the polynomial pressure projection (PPP) technique, is developed to simulate a partially propped fracture closure with the consideration of displacement discontinuity at the fracture interfaces. After that, the sequential implicit method is applied to solve the coupled problem, in which the finite volume method (FVM) and stabilized XFEM are applied to discretize the flow and geomechanics equations, respectively. Finally, the proposed method is validated through some numerical examples, and then it is further used to study the effect of partially propped fracture closures on gas production in 3D fractured shale reservoir simulation models. This work will contribute to a better understanding of the dynamic behaviors of fractured shale reservoirs during gas production, and will provide more realistic production forecasts.
first_indexed 2024-03-10T15:39:25Z
format Article
id doaj.art-5d94618db65a4f04ba1d81ba97b14f3a
institution Directory Open Access Journal
issn 1996-1073
language English
last_indexed 2024-03-10T15:39:25Z
publishDate 2020-10-01
publisher MDPI AG
record_format Article
series Energies
spelling doaj.art-5d94618db65a4f04ba1d81ba97b14f3a2023-11-20T16:57:45ZengMDPI AGEnergies1996-10732020-10-011320533910.3390/en13205339Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale ReservoirsXia Yan0Zhaoqin Huang1Qi Zhang2Dongyan Fan3Jun Yao4School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, ChinaSchool of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, ChinaDepartment of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USASchool of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, ChinaSchool of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, ChinaNonuniform proppant distribution is fairly common in hydraulic fractures, and different closure behaviors of the propped and unpropped fractures have been observed in lots of physical experiments. However, the modeling of partially propped fracture closure is rarely performed, and its effect on gas production is not well understood as a result of previous studies. In this paper, a fully coupled fluid flow and geomechanics model is developed to simulate partially propped fracture closure, and to examine its effect on gas production in fractured shale reservoirs. Specifically, an efficient hybrid model, which consists of a single porosity model, a multiple porosity model and the embedded discrete fracture model (EDFM), is adopted to model the hydro-mechanical coupling process in fractured shale reservoirs. In flow equations, the Klinkenberg effect is considered in gas apparent permeability, and adsorption/desorption is treated as an additional source term. In the geomechanical domain, the closure behaviors of propped and unpropped fractures are described through two different constitutive models. Then, a stabilized extended finite element method (XFEM) iterative formulation, which is based on the polynomial pressure projection (PPP) technique, is developed to simulate a partially propped fracture closure with the consideration of displacement discontinuity at the fracture interfaces. After that, the sequential implicit method is applied to solve the coupled problem, in which the finite volume method (FVM) and stabilized XFEM are applied to discretize the flow and geomechanics equations, respectively. Finally, the proposed method is validated through some numerical examples, and then it is further used to study the effect of partially propped fracture closures on gas production in 3D fractured shale reservoir simulation models. This work will contribute to a better understanding of the dynamic behaviors of fractured shale reservoirs during gas production, and will provide more realistic production forecasts.https://www.mdpi.com/1996-1073/13/20/5339fractured shale reservoirembedded discrete fracture modelextended finite element methodhydro-mechanical couplingpartially propped fracture closurenonuniform proppant distribution
spellingShingle Xia Yan
Zhaoqin Huang
Qi Zhang
Dongyan Fan
Jun Yao
Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
Energies
fractured shale reservoir
embedded discrete fracture model
extended finite element method
hydro-mechanical coupling
partially propped fracture closure
nonuniform proppant distribution
title Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
title_full Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
title_fullStr Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
title_full_unstemmed Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
title_short Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs
title_sort numerical investigation of the effect of partially propped fracture closure on gas production in fractured shale reservoirs
topic fractured shale reservoir
embedded discrete fracture model
extended finite element method
hydro-mechanical coupling
partially propped fracture closure
nonuniform proppant distribution
url https://www.mdpi.com/1996-1073/13/20/5339
work_keys_str_mv AT xiayan numericalinvestigationoftheeffectofpartiallyproppedfractureclosureongasproductioninfracturedshalereservoirs
AT zhaoqinhuang numericalinvestigationoftheeffectofpartiallyproppedfractureclosureongasproductioninfracturedshalereservoirs
AT qizhang numericalinvestigationoftheeffectofpartiallyproppedfractureclosureongasproductioninfracturedshalereservoirs
AT dongyanfan numericalinvestigationoftheeffectofpartiallyproppedfractureclosureongasproductioninfracturedshalereservoirs
AT junyao numericalinvestigationoftheeffectofpartiallyproppedfractureclosureongasproductioninfracturedshalereservoirs