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Experimental study and numerical modeling of the thermal behavior of an industrial prototype ceramic furnace:Energy and environmental optimization

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Energy and Built Environment 2024年第2期5卷 244-254页

作者： Lahcen BALLI Mohamed HLIMI Youssef ACHENANI Adil ATIFI Bachir HAMRI Engineering Sciences and Applications Laboratory(LSIA) National School of Applied Sciences(ENSAH)Abdelmalek Essaadi UniversityTetouanMorocco Faculty of Sciences and Techniques Moulay Ismaïl UniversityP.O.Box 509-BoutalamineErrachidiaMorocco Engineering and Health Sciences and Technologies Research Center M2SMENSAMMohammed.V UniversityRabatMorocco Research Team Quality Maintenance Safety QSMMechanical EngineeringDepartment Mohammadia School of EngineersMohammed V UniversityRabatMorocco

This article focuses on the experimental and numerical study of an industrial prototype furnace intended for the production of ceramics in order to improve the energy efficiency and therefore optimize the fuel consumption and the corresponding carbon dioxide *** order to understand the thermal behavior from which stems the energy efficiency of the experimental prototype,we establish in this work,a simplified modeling allowing to establish a mathematical model describing the thermal behavior of the *** model is able to accurately predict the spatial and temporal distribution of the temperature at each point of the furnace to control the firing of the refractory product so that the final product is of good quality in terms of resistance and *** addition,the power consumed by the prototype must be optimized in order to reduce energy and environmental *** particular,this efficient technology has allowed us to save 83% of energy used in the traditional furnace and to reduce 87.36% of the relative carbon dioxide *** simulation of the mathematical model made it possible to compare the numerical results with the experimental measurements obtained by the prototype as well as to validate the model and to adjust the heat transfer parameters.

关键词： numerical modeling Thermal behavior Ceramic furnace Refractory materials Energy efficiency

numerical modeling of metamorphic core complex formation:Implications for the destruction of the North China Craton

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Earth and Planetary Physics 2022年第2期6卷 191-203页

作者： ZiQi Ma Gang Lu JianFeng Yang Liang Zhao State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Widespread magmatism, metamorphic core complexes(MCCs), and significant lithospheric thinning occurred during the Mesozoic in the North China Craton(NCC). It has been suggested that the coeval exhumation of MCCs with uniform northwest-southeast shear senses and magmatism probably resulted from a decratonization event during the retreat of the paleo-Pacific Plate. Here we used two-dimensional finite element thermomechanical numerical models to investigate critical parameters controlling the formation of MCCs under far-field extensional stress. We observed three end-member deformation modes: the MCC mode, the symmetric-dome mode, and the pure-shear mode. The MCC mode requires a Moho temperature of ≥700 ℃ and an extensional strain rate of ≥5 × 10^(-16)s^(-1), implying that the lithosphere had already thinned when the MCC was formed in the Mesozoic. Considering that the widespread MCCs have the same northwest-southeast extension direction in the NCC, we suggest that the MCCs are surface expressions of both large-scale extension and craton destruction and that rollback of the paleo-Pacific slab might be the common driving force.

关键词： metamorphic core complex North China Craton numerical modeling extension

numerical modeling of local scour of non-uniform graded sediment for two arrangements of pile groups

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International Journal of Sediment Research 2023年第4期38卷 597-614页

作者： Saeid Okhravi Saeed Gohari Mahdi Alemi Rodrigo Maia Institute of Hydrology Slovak Academy of Sciences Department of Water Engineering College of Agriculture Bu-Ali Sina University Departamento de Engenharia Civil Faculdadede Engenharia Universidade do Porto CIIMAR-Interdisciplinary Centre of Marine and Environmental Research University of Porto

A three-dimensional(3D) non-hydrostatic numerical model is established to investigate local scour around four aligned circular piles in uniform and non-uniform sediment mixtures and to provide information for improving scour countermeasures design. In the current study, unsteady Reynolds averaged Navier-Stokes(URANS) equations along with a Re-normalization Group(RNG) k-ε model were applied to simulate the flow field. A non-uniform sediment transport model was applied to estimate the bedload transport. The simulations lasted up to 8 h. The laboratory results of a reference single pile case in uniform and non-uniform sediment were utilized to validate the simulation results of bed elevation changes and time evolution of scour depth and reflected a good agreement. The influence of pile spacing for two arrangements of pile groups, one column(tandem) and two columns(nontandem) of four aligned piles, on spatial/temporal variations of the bed surface in both sediment bed configurations are discussed in detail. The results reveal the significant effects of the pile spacing on the flow field and patterns of scour hole formation and sediment deposition. In general, lower pile spacing results in more scour upstream of the front pile(s) and shifts deposition more downstream due to the existence of higher energy in the wake region of the piles for both sediment types. Side scouring dominates for non-uniform sediment around each pile due to flow deviating because of the presence of relatively larger particles in front of the pile(s). For non-uniform sediment, deposition begins to develop at the exit area of the scour hole and enhances boundary resistance to scour. The knowledge gained from this study is suitable for the accurate determination of riprap dimensions around the front pile(s)and rear piles in a pile group.

关键词： Local bridge pier scour Non-uniform sediment numerical modeling Pile groups Pile spacing Sediment transport

numerical modeling of destress blasting for strata separation

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2238-2249页

作者： Petr Konicek Tuo Chen Hani S.Mitri Institute of Geonics Czech Academy of SciencesOstrava70800Czech Republic Department of Mining and Materials Engineering McGill UniversityMontrealH3A 0E8Canada

Destress blasting(DB)implemented along the perimeter of safety pillars is a special application of destressing in coal longwall *** goal is to separate relatively more deformed mined areas from safety pillars,such as shaft pillars or cross-cut pillars,to reduce the transfer of high stresses to the protective *** case study aims to numerically simulate selected destress blasts in the Czech part of the Upper Silesian Coal Basin and examine its impact on stress transfer to the safety pillar *** separate the area between the protective pillar and the longwall(LW),two fans of five 93-mm blast holes(length of 93e100 m)were drilled from the gate roads into the overburden *** set of blast holes was fired separately in two stages without time *** explosive charge(gelatin-type of explosive)of each stage is 3450 *** two DB stages were fired when the longwall face was approximately 158 m and 152 m away from the blast.A 3D mine-wide model is built and validated with in situ stress measured with *** and destressing in three 5-m thick coal seams are simulated in the *** modeling of DB is successfully conducted using a rock fragmentation factor a of 0.05 and a stress reduction/dissipation factor β of *** of transfer of additional stress from the mining area into the safety pillar is evaluated by comparison of yielding volume before and after *** is shown that yielding volume drops after DB by nearly 80%in the area of the destressing panel and near the safety shaft pillar.

关键词： Rockburst hazard Destress blasting(DB) Strata separation Safety pillar numerical modeling Fragmentation factor Stress dissipation factor Longwall mining

Progress in the numerical modeling of mantle plumes

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Science China Earth Sciences 2023年第4期66卷 685-702页

作者： Wei LENG Hao LIU Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Geological Processes and Mineral Resources School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China CAS Center for Excellence in Comparative Planetology Hefei 230026China

The mantle plume model, as an integral part of the Earth’s internal convection system, is complementary to the theory of plate tectonics. They together constitute the key configuration of material circulation and energy transport in the Earth’s interior. Seismology, high-temperature and high-pressure mineralogy, geology, and geodynamic numerical modeling have conducted comprehensive studies on the mantle plume model since it was proposed. In particular, numerical simulation, which investigates the dynamic processes of mantle plumes by establishing a theoretical model, provides a quantitative description of possible mantle plume evolution and the responses of the Earth’s interior and surface, which can be used to explain observations and experimental results from other disciplines. Thus, it is one of the most important means to study plume dynamics. This paper summarizes the research progress in numerical modeling of mantle plumes in past decades, including the origin of mantle plumes, seismological evidence for the existence of plumes, interactions between mantle plumes and the lithosphere, mid-ocean ridges, subduction zones, and the mantle transition zone, as well as the relationship between plumes and large low shear wave velocity provinces. The theoretical results of numerical modeling combined with observations from other disciplines enable us to deeply understand the dynamic process of mantle plumes. With the continuing development of numerical methodology and the improvement of high-performance computing, geodynamic numerical modeling will become a more accurate and efficient approach for studying mantle plume dynamics and related frontier problems in geosciences.

关键词： Mantle plume Dynamics numerical modeling

Evaluation of the performance of yielding rockbolts during rockbursts using numerical modeling method

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International Journal of Coal Science & Technology 2022年第6期9卷 25-50页

作者： Jun Wang Derek B.Apel Huawei Xu Chong Wei School of Mining and Petroleum Engineering University of AlbertaT6G 2R3 EdmontonABCanada

Rockburst;Rockburst damage;Yielding rockbolt;numerical modeling;UDEC;Underground miningThe assessment of yielding rockbolt performance during rockbursts with actual seismic loading is essential for rock-burst supporting *** this paper,two types of yielding rockbolts(D-bolt and Roofex)and the fully resin-grouted rebar bolt are modeled via the"rockbolt"element in universal distinct element code(UDEC)after an exact calibration procedure.A two-dimensional(2D)model of a deep tunnel is built to fully evaluate the performance(e.g.,capacity of energy-absorption and control of rock damage)of yielding and traditional rockbolts based on the simulated *** influence of different rockburst magnitudes is also *** results suggest that the D-bolt can effectively control and mitigate rockburst damage during a weak rockburst because of its high strength and deformation *** Roofex is too"soft"or"smooth"to limit the movement of ejected rocks and restrain the large deformation,although it has an excellent deformation *** resin-grouted rebar bolt can maintain a high axial force level during rockbursts but is easy to break during dynamic shocks,which fails to control rapid rock bulking or *** types of rockbolts cannot control the large deformation and mitigate rockburst damage effectively during violent *** rockburst damage severity can be significantly reduced by additional support with cable *** study highlights the effectiveness of numerical modeling methods in assessing the complex performance of yielding rockbolts during rockbursts,which can provide some references to improve and optimize the design of rock supporting in burst-prone grounds.

关键词： Rockburst Rockburst damage Yielding rockbolt numerical modeling UDEC Underground mining

numerical modeling and performance evaluation of passive convergence-permeable reactive barrier(PC-PRB)

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Frontiers of Environmental Science & Engineering 2023年第11期17卷 131-144页

作者： Kaixuan Zheng Dong Xie Yiqi Tan Zhenjiang Zhuo Tan Chen Hongtao Wang Ying Yuan Junlong Huang Tianwei Sun Fangming Xu Yuecen Dong Ximing Liang School of Environment Tsinghua UniversityBeijing 100084China College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

The passive convergence-permeable reactive barrier(PC-PRB)was proposed to address the limitations of traditional PRB *** evaluate the hydraulic and pollutant removal performance of the PC-PRB system,we developed a simulation code named *** code uses the two-dimensional(2D)finite element method to simulate groundwater flow and solute *** studies demonstrate that PC-PRB technology is more efficient and cost-effective than continuous permeable reactive barrier(C-PRB)in treating the same contaminated *** of PC-PRB technology results in a 33.3%and 72.7%reduction in PRB length(L_(PRB))and height(H_(PRB)),respectively,while increasing 2D horizontal and 2D vertical pollutant treatment efficiencies of PRB by 87.8%and 266.8%,*** addition,the PC-PRB technology has the ability to homogenize the pollutant concentration and pollutant flux through the PRB system,which can mitigate the problems arising from uneven distribution of pollutants in the C-PRB to some *** L_(PRB)required for PC-PRB decreases as the water pipe length(L_(p))increases,while the H_(PRB)required initially decreases and then increases with increasing L_(p).The effect of passive well height(Hw)on H_(PRB)is not as significant as that of L_(p)on H_(PRB).Overall,PC-PRB presents a promising and advantageous PRB configuration in the effective treatment of various types of contaminated plumes.

关键词： Passive convergence-permeable reactive barrier numerical modeling Hydraulic behavior assessment Pollutant treatment performance evaluation Influential factors analysis

numerical modeling of a Spar Platform Tethered by a Mooring Cable

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 785-792页

作者： ZHU Xiangqian YOO Wan-Suk Computer Aided Engineering Laboratory School of Mechanical Engineering Pusan National University

Virtual simulation is an economical and efficient method in mechanical system design. numerical modeling of a spar platform, tethered by a mooring cable with a spherical joint is developed for the dynamic simulation of the floating structure in ocean. The geometry modeling of the spar is created using finite element methods. The submerged part of the spar bears the buoyancy, hydrodynamic drag force, and effect of the added mass and Froude-Krylov force. Strip theory is used to sum up the forces acting on the elements. The geometry modeling of the cable is established based on the lumped-mass-and-spring modeling through which the cable is divided into 10 elements. A new element-fixed local frame is used, which is created by the element orientation vector and relative velocity of the fluid, to express the loads acting on the cable. The bottom of the cable is fixed on the seabed by spring forces, while the top of the cable is connected to the bottom of the spar platform by a modified spherical joint. This system suffers the propagating wave and current in the X-direction and the linear wave theory is applied for setting of the propagating wave. Based on the numerical modeling, the displacement-load relationships are analyzed, and the simulation results of the numerical modeling are compared with those by the commercial simulation code, Proteus DS. The comparison indicates that the numerical modeling of the spar platform tethered by a mooring cable is well developed, which provides an instruction for the optimization of a floating structure tethered by a mooring cable system.

关键词： numerical modeling dynamic simulation spar platform mooring cable spherical joint

numerical modeling of gas-phase kinetics in formation of secondary aerosol

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China Particuology 2007年第4期5卷 267-273页

作者： Wang-Kun Chen Ping Wang Department of Property and Environmental Management Jinwen University of Science & Technology Taipei Taiwan China Department of Civil Engineering Ching-Yun University Chungli Taiwan China

Three basic modules of gas-phase photochemical reactions involved in the formation of secondary aerosol are developed for modeling the concentration variation of precursors of aerosol, including ketone （RCOx）, aldehyde （ALD）, peroxyacetylnitrate （PAN）, NO2, and SO2, followed by numerical solution for each of the modules. Reasonable trends of concentration variation of the precursors can be obtained from the proposed modules.

关键词： Aerosol Photochemical reaction numerical modeling