Xin Liu^1,*, Kai Yan², Bo Fang³, Xiaoyu Sun³, Daqiang Feng⁴, Li Yin⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.7, pp. 1539-1552, 2024, DOI:10.32604/fdmp.2024.047922 - 23 July 2024

Abstract In response to the complex characteristics of actual low-permeability tight reservoirs, this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs, considering complex boundary shapes. Utilizing radial basis function point interpolation, the method approximates shape functions for unknown functions within the nodal influence domain. The shape functions constructed by the aforementioned meshless interpolation method have δ-function properties, which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells. Moreover, the meshless method offers greater flexibility and freedom compared to grid cell discretization, making it simpler… More >

Lifeng Liu¹, Menghe Shi², Jianhui Wang³, Wendong Wang^2,*, Yuliang Su², Xinyu Zhuang²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 595-607, 2024, DOI:10.32604/fdmp.2023.041962 - 12 January 2024

Abstract Ultra-low permeability reservoirs are characterized by small pore throats and poor physical properties, which are at the root of well-known problems related to injection and production. In this study, a gas injection flooding approach is analyzed in the framework of numerical simulations. In particular, the sequence and timing of fracture channeling and the related impact on production are considered for horizontal wells with different fracture morphologies. Useful data and information are provided about the regulation of gas channeling and possible strategies to delay gas channeling and optimize the gas injection volume and fracture parameters. It More >

Xinyu Zhou^1,2, Jia Huang^1,2, Yuchen Qian^1,2, Wenli Luo^1,2, Lisha Qi³, Jie Wang³, Zhibin Jiang³, Hao Kang^4,*

Energy Engineering, Vol.120, No.3, pp. 763-774, 2023, DOI:10.32604/ee.2023.025893 - 03 January 2023

Abstract

Due to the characteristics of reservoir formation, the producing level of low permeability reservoir is relatively very low. It is hard to obtain high recovery through conventional development schemes. Considering the tight matrix, complex fracture system, low production level of producers, and low recovery factor of M block in Xinjiang oilfield, it is selected for on-site pilot test of nitrogen foam flooding. Detailed flooding scheme is made and the test results are evaluated respectively both for producers and injectors. The pressure index, filling degree, and fluid injection profile are found to be all improved in injectors

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Wenwei Li¹, Xinjie Zhan^2,*, Baotian Wang¹, Jinyu Zuo¹

Journal of Renewable Materials, Vol.11, No.1, pp. 363-378, 2023, DOI:10.32604/jrm.2022.022254 - 10 August 2022

Abstract Municipal sludge is a sedimentation waste produced during the wastewater process in sewage treatment plants. Among recent studies, pilot and field tests showed that chemical conditioning combined with vacuum preloading can effectively treat municipal sludge. To further understand the drainage and consolidation characteristics of the conditioning sludge during vacuum preloading, a large deformation nonlinear numerical simulation model based on the equal strain condition was developed to simulate and analyze the pilot and field tests, whereas the simulation results were not satisfactory. The results of the numerical analysis of the pilot test showed that the predicted… More >

Xuanyu Dong^1,*, Jingyao Yang²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.1, pp. 175-185, 2023, DOI:10.32604/fdmp.2022.021345 - 02 August 2022

Abstract A new numerical model for low-permeability reservoirs is developed. The model incorporates the nonlinear characteristics of oil-water two-phase flows while taking into account the initiation pressure gradient. Related numerical solutions are obtained using a finite difference method. The correctness of the method is demonstrated using a two-dimensional inhomogeneous low permeability example. Then, the differences in the cumulative oil and water production are investigated for different starting water saturations. It is shown that when the initial water saturation grows, the water content of the block continues to rise and the cumulative oil production gradually decreases. More >

Yapu Zhang^1,2, Zhengming Yang^1,2, Dajian Li³, Xuewei Liu¹, Xinli Zhao^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1067-1075, 2021, DOI:10.32604/fdmp.2021.016725 - 08 September 2021

Abstract Given its relevance to the exploitation of ultra-low permeability reservoirs, which account for a substantial proportion of the world’s exploited and still unexploited reserves, in the present study the development of an adequate water injection system is considered. Due to the poor properties and weak seepage capacity of these reservoirs, the water injection pressure typically increases continuously during water flooding. In this research, the impact on such a process of factors as permeability, row spacing, and pressure gradient is evaluated experimentally using a high-pressure large-scale outcrop model. On this basis, a comprehensive evaluation coefficient is More >

Ganggang Hou¹, Tongjing Liu^{1, *}, Xinyu Yuan¹, Jirui Hou¹, Pengxiang Diwu²

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.3, pp. 1223-1246, 2020, DOI:10.32604/cmes.2020.09008 - 28 May 2020

Abstract CO₂ flooding has been widely studied and applied to improve oil recovery from low permeability reservoirs. Both the experimental results and the oilfield production data indicate that produced oil components (POC) will vary during CO₂ flooding in low permeability reservoirs. However, the present researches fail to explain the variation reason and rule. In this study, the physical model of the POC variation during CO₂ flooding in low permeability reservoir was established, and the variation reason and rule were defined. To verify the correctness of the physical model, the interaction rule of the oil-CO₂ system was studied by… More >

Jing Sun^1,2,3,*, Dehua Liu^1,2,3, Xiang Zhu^1,2,3, Wenjun Huang^1,2,3, Liang Cheng^1,2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 425-440, 2020, DOI:10.32604/fdmp.2020.08531 - 25 May 2020

Abstract Low permeability tight sandstone reservoirs have a high filtrational resistance and a very low fluid flow rate. As a result, the propagation speed of the formation pressure is low and fluid flow behaves as a non-Darcy flow, which typically displays a highly non-linear behavior. In this paper, the characteristics and mechanism of pressure propagation in this kind of reservoir are revealed through a laboratory pressure propagation experiment and through data from an actual tight reservoir development. The main performance mechanism is as follows: A new pressure cage concept is proposed based on the pressure variation… More >