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Advances in Numerical Modeling of Multiphase Flow and Heat Transfer

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A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "J1: Heat and Mass Transfer".

Deadline for manuscript submissions: closed (16 October 2024) | Viewed by 22953

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Special Issue Editors

Dr. Shaofei Zheng

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State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China
Interests: condensation enhanced heat transfer; wetting kinetics and interface phenomena; heat and mass transfer; multiphase flow; aero-engine turbine blade cooling technology

Dr. Jian Liu

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Research Institute of Aerospace Technology, Central South University, Changsha 410012, China
Interests: gas turbine; convective heat transfer; film cooling; transpiration cooling; scramjet; powder fuel; porous media; combustion; PIV; experimental heat transfer
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Dr. Liu Liu

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Guest Editor

School of Energy Science and Engineering, Central South University, Changsha 410083, China
Interests: multiphase flow; bubble dynamics; heat and mass transfer; computational fluid dynamics

Dr. Han Shen

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Guest Editor

Shaanxi Key Laboratory of Space Solar Power Station System, School of Mechano-Electronic Engineering, Xidian University, Xi'an 710071, China
Interests: thermal structure design; heat and mass transfer; topology optimization design; heat transfer enhancement; information technology

Prof. Dr. Bengt Sunden

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Lund University, P.O. Box 118, 22100 Lund, Sweden
Interests: multiphase flow; phase change heat transfer; heat and mass transfer; PEM fuel cells; batteries; hydrogen production and storage; gas turbine cooling
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Xiaodong Wang

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State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China
Interests: wetting dynamics and interface phenomenon; micro/nano-scale multiphase flow and heat transfer; phase-change heat and mass transfer; PEM fuel cells; micro-energy systems

Special Issue Information

Dear Colleagues,

Energy systems typically involve multiphase flow and heat transfer. Substantial examples can be found in heat pipes, power plants, gas turbines, chemical reactors, and fuel cells. The process performance and reliability of these systems strongly depend on the fundamental understanding of thermal-fluid processes which has an urgent demand for highly accurate and reliable modeling methods. Multiphase flow and heat transfer widely couples various physical processes, including fluid flow, heat transfer, mass transfer, phase change, reaction, multiscale characteristics, spatio-temporal transient characteristics, interface generation and evolution, and multicomponent flow. The corresponding numerical modeling is still a great challenge and has attracted continuous research attention.

This Special Issue aims to introduce the latest development direction and outstanding advances in multiphase flow and heat transfer. Topics include but not limited to the numerical modeling of multiphase flow and heat transfer in various applications. Modeling works including model development and numerical investigations involving multiphase flow and heat transfer are all welcome for submission to this Special Issue.

Dr. Shaofei Zheng
Dr. Jian Liu
Dr. Liu Liu
Dr. Han Shen
Prof. Dr. Bengt Sunden
Prof. Dr. Xiaodong Wang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

multiscale modeling and computation
multiphase multicomponent flow
gas–liquid two-phase flow
condensation and boiling
reaction flow
heat and mass transfer
wetting dynamics
interface phenomenon

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Published Papers (14 papers)

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Research

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15 pages, 649 KiB

Open AccessArticle

Computing Interface Curvature from Height Functions Using Machine Learning with a Symmetry-Preserving Approach for Two-Phase Simulations

by Antonio Cervone, Sandro Manservisi, Ruben Scardovelli and Lucia Sirotti

Energies 2024, 17(15), 3674; https://doi.org/10.3390/en17153674 - 25 Jul 2024

Cited by 1 | Viewed by 946

Abstract

The volume of fluid (VOF) method is a popular technique for the direct numerical simulations of flows involving immiscible fluids. A discrete volume fraction field evolving in time represents the interface, in particular, to compute its geometric properties. The height function method (HF) is based on the volume fraction field, and its estimate of the interface curvature converges with second-order accuracy with grid refinement. Data-driven methods have been recently proposed as an alternative to computing the curvature, with particular consideration for a well-balanced input data set generation and symmetry preservation. In the present work, a two-layer feed-forward neural network is trained on an input data set generated from the height function data instead of the volume fraction field. The symmetries for rotations and reflections and the anti-symmetry for phase swapping have been considered to reduce the number of input parameters. The neural network can efficiently predict the local interface curvature by establishing a correlation between curvature and height function values. We compare the trained neural network to the standard height function method to assess its performance and robustness. However, it is worth noting that while the height function method scales perfectly with a quadratic slope, the machine learning prediction does not. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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20 pages, 5004 KiB

Open AccessArticle

Multiphase Flow’s Volume Fractions Intelligent Measurement by a Compound Method Employing Cesium-137, Photon Attenuation Sensor, and Capacitance-Based Sensor

by Abdulilah Mohammad Mayet, Farhad Fouladinia, Robert Hanus, Muneer Parayangat, M. Ramkumar Raja, Mohammed Abdul Muqeet and Salman Arafath Mohammed

Energies 2024, 17(14), 3519; https://doi.org/10.3390/en17143519 - 18 Jul 2024

Cited by 1 | Viewed by 971

Abstract

Multiphase fluids are common in many industries, such as oil and petrochemical, and volume fraction measurement of their phases is a vital subject. Hence, there are lots of scientists and researchers who have introduced many methods and equipment in this regard, for example, photon attenuation sensors, capacitance-based sensors, and so on. These approaches are non-invasive and for this reason, are very popular and widely used. In addition, nowadays, artificial neural networks (ANN) are very attractive in a lot of fields and this is because of their accuracy. Therefore, in this paper, to estimate volume proportion of a three-phase homogeneous fluid, a new system is proposed that contains an MLP ANN, standing for multilayer perceptron artificial neural network, a capacitance-based sensor, and a photon attenuation sensor. Through computational methods, capacities and mass attenuation coefficients are obtained, which act as inputs for the proposed network. All of these inputs were divided randomly in two main groups to train and test the presented model. To opt for a suitable network with the lowest rate of mean absolute error (MAE), a number of architectures with different factors were tested in MATLAB software R2023b. After receiving MAEs equal to 0.29, 1.60, and 1.67 for the water, gas, and oil phases, respectively, the network was chosen to be presented in the paper. Hence, based on outcomes, the proposed approach’s novelty is being able to predict all phases of a homogeneous flow with very low error. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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17 pages, 3929 KiB

Open AccessArticle

Kinetic Model Implementation of Fluidized Bed Devolatilization

by Armando Vitale, Andrea Di Carlo, Pier Ugo Foscolo and Alessandro Antonio Papa

Energies 2024, 17(13), 3154; https://doi.org/10.3390/en17133154 - 26 Jun 2024

Cited by 2 | Viewed by 1359

Abstract

Computational modeling is a powerful tool for studying and investigating the behavior of fluidized bed gasifiers and the modeling of the initial devolatilization step is necessary to provide a reliable description of the whole process involving the feedstock decomposition and the subsequent gasification reaction. In this work, a bench-scale fluidized bed reactor was used to examine the devolatilization of different carbonaceous materials within the temperature range from 650 to 850 °C. The experimental test campaign was used to derive the linear correlation factor to describe the devolatilization in terms of product distribution as a function of temperature and highlight the different behavior between lignocellulosic and plastic feedstocks. Furthermore, the experimental data were used to develop concise kinetic expressions able to fit the experimental devolatilization times ranging from 75 in the case of poplar at a lower temperature and 22 s for the Organic Fraction of Municipal Solid Waste (OFMSW) at a higher temperature. The obtained model produces a simple kinetic expression where the size of the particle is enclosed in the kinetic parameters. The kinetic model sided by the application of linear correlations describes the overall thermal decomposition in a fluidized bed, simplifying its modeling in commercial simulation software, even when particles are considered as point-like bodies. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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18 pages, 6994 KiB

Open AccessArticle

Numerical Study of Heat Transfer and Fluid Flow Characteristics of a Hydrogen Pulsating Heat Pipe with Medium Filling Ratio

by Dongyu Yang, Zhicheng Bu, Bo Jiao, Bo Wang and Zhihua Gan

Energies 2024, 17(11), 2697; https://doi.org/10.3390/en17112697 - 2 Jun 2024

Viewed by 816

Abstract

Benefiting from its high thermal conductivity, simple structure, and light weight, the pulsating heat pipe (PHP) can meet the requirements for high efficiency, flexibility, and low cost in industrial heat transfer applications such as aerospace detector cooling and vehicle thermal management. Compared to a PHP working at room temperature, the mechanism of a PHP with hydrogen as the working fluid differs significantly due to the unique thermal properties of hydrogen. In this paper, a two-dimensional model of a hydrogen PHP with a filling ratio of 51% was established to study the flow characteristics and thermal performance. The volume of fluid (VOF) method was used to capture the phase distribution and interface dynamics, and the Lee model was employed to account for phase change. To validate the model, a comparison was conducted between the simulation results and experimental data obtained in our laboratory. The simulation results show that the pressure and temperature errors were within 25% and 5%, respectively. Throughout a pressure oscillation cycle, the occurrence of uniform flow velocity, acceleration, and flow reversal can be attributed to the changes in the vapor–liquid phase distribution resulting from the effect of condensation and evaporation. In addition, when the fluid velocity was greater than 0.6 m/s, dynamic contact angle hysteresis was observed in the condenser. The results contribute to a deeper understanding of the flow and heat transfer mechanism of the hydrogen PHPs, which have not been yet achieved through visualization experiments. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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15 pages, 6032 KiB

Open AccessArticle

Numerical Investigation of a Two-Phase Ejector Operation Taking into Account Steam Condensation with the Presence of CO₂

by Tomasz Kuś and Paweł Madejski

Energies 2024, 17(9), 2236; https://doi.org/10.3390/en17092236 - 6 May 2024

Cited by 1 | Viewed by 1207

Abstract

The application of a two-phase ejector allows for the mixing of liquid and gas and provides effective heat transfer between phases. The aim of the study is a numerical investigation of the performance of a water-driven, condensing two-phase ejector. The research was performed using CFD methods, which can provide an opportunity to analyze this complex phenomenon in 2D or 3D. The 2D axisymmetric model was developed using CFD software Siemens StarCCM+ 2022.1.1. The Reynolds-Averaged Navier–Stokes (RANS) approach with the Realisable k-ε turbulence model was applied. The multiphase flow was calculated using the mixture model. The boiling/condensation model, where the condensation rate is limited by thermal diffusion, was applied to take into account direct contact condensation. Based on the mass balance calculations and developed pressure and steam volume fraction distributions, the ejector performance was analyzed for various boundary conditions. The influence of the suction pressure (range between 0.812 and 0.90) and the steam mass flow rate (range between 10 g/s and 25 g/s) is presented to investigate the steam condensation phenomenon inside the ejector condenser. The provided mixture of inert gas (CO₂) with steam (H₂O) in the ejector condenser was investigated also. The weakening of the steam condensation process by adding CO₂ gas was observed, but it is still possible to achieve effective condensation despite the presence of inert gas. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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19 pages, 7945 KiB

Open AccessArticle

Numerical Simulation on Two-Phase Ejector with Non-Condensable Gas

by Yinghua Chai, Yuansheng Lin, Qi Xiao, Chonghai Huang, Hanbing Ke and Bangming Li

Energies 2024, 17(6), 1341; https://doi.org/10.3390/en17061341 - 11 Mar 2024

Cited by 1 | Viewed by 1046

Abstract

The two-phase ejector is a simple and compact pressure boosting device and widely used in ejector steam-generator water feeding systems and core emergency cooling systems. The direct contact condensation of water and steam is the key process of a two-phase ejector. Usually, the high-temperature and high-pressure steam will inevitably induce non-condensable gases. The existence of non-condensable gases will reduce the condensation heat transfer rate between steam and water, and harm the equipment. This study carried out 3D numerical simulations of a two-phase ejector based on an inhomogeneous multiphase model. The steam inlet pressure and the non-condensable gas mass fraction rang in 0.6–2.9 MPa and 1–10%, respectively. The heat and mass transfer characteristics were analyzed under different conditions. The results show that the heat transfer coefficient and plume penetration length increased with the steam inlet pressure. Non-condensable gas prevents direct contact condensation between the steam and water. The non-condensable gas mass fraction rises from 1% to 10%, the heat transfer between steam and water deteriorates, and leads to a lower heat transfer coefficient. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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18 pages, 5083 KiB

Open AccessArticle

Enhancing Efficiency in Alkaline Electrolysis Cells: Optimizing Flow Channels through Multiphase Computational Fluid Dynamics Modeling

by Longchang Xue, Shuaishuai Song, Wei Chen, Bin Liu and Xin Wang

Energies 2024, 17(2), 448; https://doi.org/10.3390/en17020448 - 16 Jan 2024

Cited by 2 | Viewed by 3614

Abstract

The efficient operation of alkaline water electrolysis cells hinges upon understanding and optimizing gas–liquid flow dynamics. Achieving uniform flow patterns is crucial to minimize stagnant regions, prevent gas bubble accumulation, and establish optimal conditions for electrochemical reactions. This study employed a comprehensive, three-dimensional computational fluid dynamics Euler–Euler multiphase model, based on a geometric representation of an alkaline electrolytic cell. The electrochemical model, responsible for producing hydrogen and oxygen at the cathode and anode during water electrolysis, is integrated into the flow model by introducing mass source terms within the user-defined function. The membrane positioned between the flow channels employs a porous medium model to selectively permit specific components to pass through while restricting others. To validate the accuracy of the model, comparisons were made with measured data available in the literature. We obtained an optimization design method for the channel structure; the three-inlet model demonstrated improved speed and temperature uniformity, with a 22% reduction in the hydrogen concentration at the outlet compared to the single-inlet model. This resulted in the optimization of gas emission efficiency. As the radius of the spherical convex structure increased, the influence of the spherical convex structure on the electrolyte intensified, resulting in enhanced flow uniformity within the flow field. This study may help provide recommendations for designing and optimizing flow channels to enhance the efficiency of alkaline water electrolysis cells. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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27 pages, 19375 KiB

Open AccessArticle

Numerical Simulation of Turbulent Structure and Particle Deposition in a Three-Dimensional Heat Transfer Pipe with Corrugation

by Hao Lu, Yu Wang, Hongchang Li and Wenjun Zhao

Energies 2024, 17(2), 321; https://doi.org/10.3390/en17020321 - 9 Jan 2024

Cited by 7 | Viewed by 1416

Abstract

When colloidal particles are deposited in a heat transfer channel, they increase the flow resistance in the channel, resulting in a substantial decrease in heat transfer efficiency. It is critical to have a comprehensive understanding of particle properties in heat transfer channels for practical engineering applications. This study employed the Reynolds stress model (RSM) and the discrete particle model (DPM) to simulate particle deposition in a 3D corrugated rough-walled channel. The turbulent diffusion of particles was modeled with the discrete random walk model (DRW). A user-defined function (UDF) was created for particle–wall contact, and an improved particle bounce deposition model was implemented. The research focused on investigating secondary flow near the corrugated wall, Q-value standards, turbulent kinetic energy distribution, and particle deposition through validation of velocity in the tube and particle deposition modeling. The study analyzed the impact of airflow velocity, particle size, corrugation height, and corrugation period on particle deposition efficiency. The findings suggest that the use of corrugated walls can significantly improve the efficiency of deposition for particles less than 20 μm in size. Specifically, particles with a diameter of 3 μm showed five times higher efficacy of deposition with a corrugation height of 24 mm compared to a smooth surface. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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19 pages, 11082 KiB

Open AccessArticle

Analysis of Interaction and Flow Pattern of Multiple Bubbles in Shear-Thinning Viscoelastic Fluids

by Hongbin He, Zhuang Liu, Jingbo Ji and Shaobai Li

Energies 2023, 16(14), 5345; https://doi.org/10.3390/en16145345 - 13 Jul 2023

Cited by 2 | Viewed by 1313

Abstract

A numerical study was conducted on the interaction of bubbles with different diameters and arrangements in shear-thinning viscoelastic fluids using OpenFOAM. The Volume of Fluid (VOF) method combined with the surface tension model was used to track the gas–liquid interface, and the rheological properties of the fluid were characterized with the Giesekus model. The numerical results are corresponded with the previous references, verifying the correctness of the simulation method. The influences of the initial bubble diameter, horizontal spacing, and arrangement on the motion state of three parallel bubbles were studied in detail. The flow pattern of the bubble rising was analyzed and compared with the motion state of parallel unequal double bubbles. As the diameter of the bubbles increases, the interaction among three equal size bubbles is changed from coalescence to detachment. Changing the diameter of one of the bubbles will significantly affect the movement of the larger diameter bubble, which is due to the enhancement in kinetic energy. The final state of some arrangement ways is consistent with the phenomenon of unequal double bubbles. The shear thinning effect, the velocity difference between bubbles, and the flow field around bubbles are considered the main reasons that decide the interaction between bubbles. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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Review

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23 pages, 3137 KiB

Open AccessReview

Study of the Dynamics of a Single Bubble

by Anatoliy Pavlenko and Hanna Koshlak

Energies 2024, 17(17), 4236; https://doi.org/10.3390/en17174236 - 24 Aug 2024

Cited by 1 | Viewed by 1342

Abstract

The behaviour of bubbles in cavitation and boiling processes is determined by the thermodynamic parameters of the two-phase medium and the intensity of heat and mass transfer, which affect the final dynamic effects. In this review, we analyse the influences of these factors on bubble behaviour, as described in existing mathematical models. In particular, we analyse the physical processes that govern bubble behaviour, the influence of mass transfer, vapor and liquid temperature, vapour, and liquid pressure on the inertial and dynamic stages of development. In conclusion, we summarize the problems associated with modelling, the accuracy of numerical predictions, and propose directions for further research. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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60 pages, 809 KiB

Open AccessFeature PaperReview

Recent Progress in Heat and Mass Transfer Modeling for Chemical Vapor Deposition Processes

by Łukasz Łach and Dmytro Svyetlichnyy

Energies 2024, 17(13), 3267; https://doi.org/10.3390/en17133267 - 3 Jul 2024

Cited by 2 | Viewed by 2531

Abstract

Chemical vapor deposition (CVD) is a vital process for deposit of thin films of various materials with precise control over the thickness, composition, and properties. Understanding the mechanisms of heat and mass transfer during CVD is essential for optimizing process parameters and ensuring high-quality film deposition. This review provides an overview of recent advancements in heat and mass transfer modeling for chemical vapor deposition processes. It explores innovative modeling techniques, recent research findings, emerging applications, and challenges in the field. Additionally, it discusses future directions and potential areas for further advancement in CVD modeling. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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21 pages, 3187 KiB

Open AccessFeature PaperReview

Advancements and Prospects of Hydrogel Sweat Cooling Technology in Multiphase Heat Transfer Applications: A Review

by Liang Xu, Jiren Li, Lei Xi, Yunlong Li and Jianmin Gao

Energies 2024, 17(13), 3152; https://doi.org/10.3390/en17133152 - 26 Jun 2024

Viewed by 1657

Abstract

Hydrogel sweat cooling is one of the leading areas in the study of multiphase heat transfer. In this study, the principles, applications, current research status, and future trends of hydrogel sweat cooling technology are comprehensively reviewed. By combing through and analyzing the relevant literature, the research progress in hydrogel sweat cooling is presented from the application perspective, including its use in electronic devices, buildings, and clean-energy facilities. The principle of each application is illustrated, the research status is established, and pros and cons are proposed. To provide inspiration for future research, the development trend is set out. Our literature review indicates that research on advanced hydrogels is the most promising research direction, including studies on the effect of environmental and indoor factors on sweat cooling performance through numerical, experimental, and theoretical means. Challenges for future research mainly include conducting hydrogel numerical analysis which can be experimentally verified, developing advanced hydrogels in a green way, and achieving the precise regulation of hydrogel control through intelligent methods. Interdisciplinary integration might be promising as well due to the fact that it can reveal the hydrogel sweat cooling mechanism from a different perspective. This study aims to promote multiphase cooling technology in exploring the application of hydrogels in energy utilization criteria. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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24 pages, 959 KiB

Open AccessReview

Modeling of Heat and Mass Transfer in Cement-Based Materials during Cement Hydration—A Review

by Barbara Klemczak, Aneta Smolana and Agnieszka Jędrzejewska

Energies 2024, 17(11), 2513; https://doi.org/10.3390/en17112513 - 23 May 2024

Cited by 2 | Viewed by 1573

Abstract

Cement-based materials encompass a broad spectrum of construction materials that utilize cement as the primary binding agent. Among these materials, concrete stands out as the most commonly employed. The cement, which is the principal constituent of these materials, undergoes a hydration reaction with water, playing a crucial role in the formation of the hardened composite. However, the exothermic nature of this reaction leads to significant temperature rise within the concrete elements, particularly during the early stages of hardening and in structures of substantial thickness. This temperature rise underscores the critical importance of predictive modeling in this domain. This paper presents a review of modeling approaches designed to predict temperature and accompanying moisture fields during concrete hardening, examining different levels of modeling accuracy and essential input parameters. While modern commercial finite element method (FEM) software programs are available for simulating thermal and moisture fields in concrete, they are accompanied by inherent limitations that engineers must know. The authors further evaluate effective commercial software tools tailored for predicting these effects, intending to provide construction engineers and stakeholders with guidance on managing temperature and moisture impacts in early-age concrete. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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17 pages, 6306 KiB

Open AccessReview

Modeling and Numerical Investigations of Gas Production from Natural Gas Hydrates

by Zi-Jie Ning, Hong-Feng Lu, Shao-Fei Zheng, Dong-Hui Xing, Xian Li and Lei Liu

Energies 2023, 16(20), 7184; https://doi.org/10.3390/en16207184 - 21 Oct 2023

Viewed by 1694

Abstract

As ice-like crystals and non-stoichiometric compounds comprising gas and water, natural gas hydrates have drawn significant attention as a potential alternative energy source. This work focuses on holistically reviewing theoretical modeling and numerical studies conducted on the production of gas from natural gas hydrates. Firstly, fundamental models for the dissociation of a hydrate in a porous sediment are summarized in terms of the phase equilibrium and dissociation kinetics. The main features of different models and improvements for them are identified by clarifying crucial driving mechanisms and kinetic parameters. Subsequently, various numerical works addressing the dissociation of a hydrate in a porous sediment and the flow characteristics in a wellbore are reviewed, including aspects such as the theoretical background, computational scheme, and the physics involved. In general, profiting from a significant capacity to solve nonlinear differential equations, numerical simulations have contributed to great progress in fundamentally understanding the mechanism driving gas production and in developing effective exploitation methods. Owing to the substantial fundamental physics involved in the exploitation of natural gas hydrates, existing challenges, alternative strategies, and future directions are provided correspondingly from a practical application perspective. Full article

(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)

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