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International Journal of Mining Science and Technology 2022年第2期32卷 237-245页

作者： A.karrech X.Dong M.Elchalakani H.Basarir M.A.Shahin k.regenauer-lieb School of Engineering University of Western AustraliaCrawleyWA 6009Australia Department of Geoscience and Petroleum Norwegian University of Science and TechnologyTrondheim 7031Norway School of Civil and Mechanical Engineering Curtin UniversityPerth 6102Australia School of Minerals and Energy Resources Engineering UNSWSydneyNSW 2052Australia

The parameters that influence slope stability and their criteria of failure are fairly understood but over-conservative design approaches are often preferred,which can result in excessive overburden removal that may jeopardize profitability in the context of open pit *** methods such as finite element and discrete element modelling are instrumental to identify specific zones of stability,but they remain approximate and do not pinpoint the critical factors that influence stability without extensive parametric studies.A large number of degrees of freedom and input parameters may make the outcome of numerical modelling insufficient compared to analytical *** analytical approaches have not tackled the stability of slopes using non-linear plasticity criteria and threedimensional failure *** paper bridges this gap by using the yield design theory and the Hoek-Brown ***,the proposed model includes the effect of seismic forces,which are not always taken into account in slope stability *** results are presented in the form of rigorous mathematical expressions and stability charts involving the loading conditions and the rock mass properties emanating from the plasticity criterion.

关键词： Three-dimensional slope Seismic stability Generalized Hoek-Brown criterion Open pit

Microsesmicity in non-volcanic environments: Source depth, origin of fluids and tectonic driver for Episodic Tremor and Slip Sequences

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Microsesmicity in non-volcanic environments: Source depth, o...

Replacement of annular domain with trapezoidal domain in computational modeling of nonaqueous-phase-liquid dissolution-front propagation problems

2014年中国地球科学联合学术年会——国际专题（2）Microseismic Monitoring and Inversion

作者： E.Veveakis T.Poulet k.regenauer-lieb D.A.Yuen CSIRO Earth Science and Resource Engineering School of Mathematics and Statistics University of Western Australia School of Earth and Environment University of Western Australia School of Environmental Studies Chinese University of Geosciences Minnesota Supercomputer Institute Department of Earth Sciences University of Minnesota

A peculiar observation,revealed through recent advances in monitoring seismicity,is the slow seismic activity recorded in the interface of subduction zone and overriding ***,the response of the overriding plate to the load applied by the subduction process is divided into two distinctly different *** shallow portion of the overriding plate is considered to be seismogenic,while the deep zone is considered to be *** natural conclusion is that the deep portion does not contribute to the activity other than providing a damping dissipation of instabilities near the surface.

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Journal of Central South University 2015年第5期22卷 1841-1846页

作者：赵崇斌 Thomas POULET klaus regenauer-lieb Computational Geosciences Research Centre Central South University CSIRO Division of Earth Science and Resource Engineering P.O.Box 1130 Bentley WA 6102 Australia School of Earth and Environment The University of Western Australia

In order to simulate the instability phenomenon of a nonaqueous phase liquid(NAPL) dissolution front in a computational model, the intrinsic characteristic length is commonly used to determine the length scale at which the instability of the NAPL dissolution front can be initiated. This will require a huge number of finite elements if a whole NAPL dissolution system is simulated in the computational model. Even though modern supercomputers might be used to tackle this kind of NAPL dissolution problem, it can become prohibitive for commonly-used personal computers to do so. The main purpose of this work is to investigate whether or not the whole NAPL dissolution system of an annular domain can be replaced by a trapezoidal domain, so as to greatly reduce the requirements for computer efforts. The related simulation results have demonstrated that when the NAPL dissolution system under consideration is in a subcritical state, if the dissolution pattern around the entrance of an annulus domain is of interest, then a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution ***, if the dissolution pattern away from the vicinity of the entrance of an annulus domain is of interest, then a trapezoidal domain can be used to replace an annular domain in the computational simulation of the NAPL dissolution system. When the NAPL dissolution system under consideration is in a supercritical state, a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution system.

关键词： nonaqueous phase liquid(NAPL) trapezoidal domain computational simulation dissolution front instability

Rock Plasticity from Microtomography and Upscaling

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Journal of Earth Science 2015年第1期26卷 53-59页

作者： Jie Liu Reem Freij-Ayoub klaus regenauer-lieb School of Earth Science and Geological Engineering Sun Yat-Sen University School of Earth and Environment the University of Western AustraliaPerth WA 6000Australia Earth Science and Resource Engineering CSIROKensington WA 6151Australia School of Petroleum Engineering University of New South WalesSydney NSW 2052Australia

We present a workflow for upscaling of rock properties using microtomography and percolation theory. In this paper we focus on a pilot study for assessing the plastic strength of rocks from a digital rock image. Firstly, we determine the size of mechanical representative volume ele- ment （RVE） by using upper/lower bound dissipation computations in accordance with thermody- namics. Then the mechanical RVE is used to simulate the rock failure at micro-scale using FEM. Two cases of different pressures of linear Drucker-Prager plasticity of rocks are computed to compute the macroscopic cohesion and the angle of internal friction of the rock. We also detect the critical exponents of yield stress for sealing laws from a series of derivative models that are created by a shrinking/expanding algorithm. We use microtomographic data sets of two carbonate samples and compare the results with previous results. The results show that natural rock samples with irregular structures may have the critical exponent of yield stress different from random models. This unexpected result could have significant ramifications for assessing the stability of solid materials with internal structure. Therefore our pilot study needs to be extended to investigate the scaling laws of strength of many more natural rocks with irregular microstructure.

关键词： plastic strength rock mierotomography percolation theory upscaling.

Borehole deformation based in situ stress estimation using televiewer data

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2475-2481页

作者： Hamid Roshan Danqi Li Ismet Canbulat klaus regenauer-lieb School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW2052Australia WA School of Mines MineralsEnergy and Chemical EngineeringCurtin UniversityPerthWA6102Australia

The knowledge of in situ stress is critical in safe and optimised extraction of minerals and energy *** situ stresses are either measured directly(***)or estimated indirectly(*** breakouts).Borehole breakout analysis for in situ stress estimation is considered a relatively simple and cost-efficient *** technique,however,poses certain limitations such as complexities with progressive formation of breakouts and it requires inputs such as rock failure parameters that are not often *** a result,significant effort has been made to develop new indirect methods for in situ stress *** deformation analysis using four-arm caliper has been recently proposed for in situ stress estimation and has shown promising *** this study,we demonstrate a new methodology that analyses the borehole televiewer data with the technique of borehole deformation analysis to estimate the in situ stresses through a field case *** advantages and challenges of using borehole televiewer data for stress estimation based on borehole deformation analysis are discussed and the best practice to obtain the reliable results is *** limitations of using fourarm caliper and borehole deformation analysis for in situ stress estimation are also discussed and it is shown how televiewer data can overcome such ***,the in situ stress results obtained from televiewer data and borehole deformation analysis are compared with independent in situ stress measurements to show the robustness and reliability of the proposed methodology.

关键词： In situ stress Borehole deformation Televiewer Elastic properties Downhole logging

Coupling of Thermal-Hydraulic-Mechanical Processes for Geothermal Reservoir Modelling

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Journal of Earth Science 2015年第1期26卷 47-52页

作者： Ali karrechl Oussama Beltaief Ruyan Vincec Thomas Poulet klaus regenauer-lieb School of Civil and Resource Engineering The University of Western AustraliaCrawley WA 6009Australia Tunisia Polytechnic School Rue AlkhawarizmiLa MarsaTunisia Earth Science and Resource Engineering CSIROKensington WA 6151Australia School of Petroleum Engineering University of New South WalesSydney NSW 2052Australia School of Earth and Environment The University of Western AustraliaPerth WA 6000Australia

This paper uses a fully coupled framework of thermal-hydraulic-mechanical processes to investigate how the injection and extraction of fluid within a geothermal reservoir impacts on the distributions of temperature, pore pressure, and deformation within the rock formations. Based on this formulation, a numerical model is developed in light of the thermodynamics of porous materials. The proposed procedure relies on the derivation of dissipative flow rules by postulating proper storage and dissipation functions. This approach opens new horizons for several resource engineering applications. Since it allows for full coupling, this formulation can play a key role in predicting risks when used for reservoir simulation. The results indicate that the injection-extraction process and temperature change have a definite impact on altering the in-situ properties of the reservoir.

关键词： poro-mechanics resource engineering fluid injection and extraction temperaturechange pore pressure stress deformation uplift subsidence.

Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while keeping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k,350 k and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer