Continuum Mechanics Research Articles

Research on multi-scale hysteresis constitutive model of giant magnetostrictive materials considering multi-field coupling

The magnetization and magnetostrictive strain of giant magnetostrictive materials exhibit a complex nonlinear trend under the coupling of multiple fields, including magnetic field, temperature field, and prestress field. To enhance prediction accuracy, we propose a three-dimensional magnetic-thermal-force coupled nonlinear multi-scale hysteresis vector model. This model is derived from the principles of thermodynamics and continuum mechanics, taking into account the interactions among magnetic domains, grains, polycrystals, and macroscopic scales. It combines the volume-averaging principle of magnetic domain microscopy with the generalized Jiles-Atherton hysteresis model. The predicted hysteresis magnetization and magnetostrictive strain curves obtained from this model are in good agreement with experimental results. By analyzing the predicted hysteresis magnetization and magnetostrictive strain under different conditions, we demonstrate that our proposed model can comprehensively describe the effects of temperature and prestress on the multi-field coupled hysteresis behaviors of giant magnetostrictive materials. Moreover, it provides theoretical guidance for both macroscopic and microscopic optimization in designing active devices incorporating super magnetostrictive materials.

Vibrational analysis of graphyne-based nanoplates using a hybrid nonlocal strain gradient-atomistic simulation model

By employing a hybrid atomistic-continuum model, we can combine the advantages of atomic and continuum models. In this approach, resonance frequencies are matched to those obtained from the continuum model using the size effect and Young’s modulus as fit parameters. Our proposed method examines how radius affects the elastic modulus, size effect parameters, and resonance frequency values of the graphyne family, taking into account both macro and nano-scale models. The non-local strain gradient model has been calibrated to achieve optimal error. In contrast, the error is highest when the non-local strain gradient effect is not considered in the continuum mechanics model.

Towards improved online dissolution evaluation of Pt-alloy PEMFC electrocatalysts via electrochemical flow cell - ICP-MS setup upgrades

Electrochemical flow cell coupled with an inductively coupled plasma mass spectrometer (EFC-ICP-MS) is a powerful electroanalytical technique to monitor in-situ dissolution of metallic electrocatalysts and to understand mechanism of degradation under operating conditions. Its utilisation has witnessed a notable increase in the electrocatalyst field in the last decade where it has been extensively used to study the stability of platinum group metals (PGMs) under oxygen reduction and oxygen evolution reaction conditions. Online ICP-MS has allowed the scientific and industrial community to optimise the activity and stability of PGMs thanks to a better understanding of the complex metal corrosion processes. Among the different setups, the electrochemical flow cell design is the most common as it is based on a commercially available design. Nonetheless, besides different materials and different electrochemical protocols, the impact of the geometry and various parameters of the setup on the recorded dissolution signal has not been studied until now. Such parameters can influence the results obtained with an EFC-ICP-MS and thus the interpretation of the dissolution mechanism and/or stability assessment. Hereby, we demonstrate that the length of the tubing between the outlet of the cell and the inlet of the ICP-MS impacts the resolution of the PtCo catalyst dissolution peaks. This, in turn, facilitates studies where the detection of extremely low concentrations is necessary, such as under a very narrow potential window. Similarly, a reduced internal volume of the cell restricts Pt redeposition, contributing to a more precise evaluation of stability. These claims were supported by dynamic continuum mechanics modelling of the ion concentration in a model EFC. Finally, we provide guidelines and advice to properly measure dissolution with an electrochemical cell coupled with ICP-MS.

Preface

The Center for Space Plasma and Aeronomic Research (CSPAR) at the University of Alabama in Huntsville (UAH) and Maison de la Simulation, a joint laboratory at the French Alternative Energies and Atomic Energy Commission (CEA), National Center for Scientific Research (CNRS), University of Paris-Saclay, and University of Versailles-St Quentin, organized the 15th International Conference on Numerical Modeling of Space Plasma Flows (ASTRONUM-2023) on June 26—30, 2023 in Pasadena, California, USA.The Program Committee consisted of Nikolai Pogorelov (University of Alabama in Huntsville/CSPAR, USA, chair), Edouard Audit (CEA Maison de la Simulation, Gif-sur-Yvette, France, co-chair), Wes Bethel (San Francisco State University, USA), Amitava Bhattacharjee (Princeton Plasma Physics Laboratory, USA), Phillip Colella (Lawrence Berkeley National Laboratory, USA), Tomoyuki Hanawa (Chiba University, Japan), Maria Elena Innocenti (Ruhr University Bochum, Germany), Kanya Kusano (Nagoya University, Japan), Dongwook Lee (University of California, Santa Cruz), Jon Linker (Predictive Science Inc., USA), Anthony Mezzacappa (University of Tennessee, Knoxville, USA), Ewald Müller (Max-Planck-Institute for Astrophysics, Garching, Germany), Dongsu Ryu (Ulsan National Institute of Science and Technology, Korea), James Stone (Princeton University), and Gary P. Zank (University of Alabama in Huntsville, USA).The conference attracted over 90 scientists from 15 countries representing different branches of the plasma simulation community. The distinctive feature of this conference is a combination of diverse research topics, all of which are essential for performing high-resolution, continuum mechanics and particle, simulations of physical phenomena in space physics and astrophysics. Among such topics were software packages for modeling and analyzing plasma flows; advanced numerical methods for space and astrophysical flows; large-scale fluid-based, kinetic, and hybrid simulations; turbulence and cosmic ray transport; and magnetohydrodynamics. The discussed applications included cosmology and galaxy formation, supernova explosions, physics of the Sun-heliosphere-magnetosphere environments, space weather, the interstellar medium and star formation, stellar physics, experimental plasma physics, astrophysical accretion, numerical methods for ideal and non-ideal, relativistic and nonrelativistic MHD, etc. The proceedings volume is structured so that it covers all of these topics.The structure of the ASTRONUM conference series is based on the idea that modelers working in seemingly distant fields should have an opportunity to share their scientific achievements with the broad community of computational scientists performing numerical experiments. As in previous ASTRONUM meetings, we were interested in physical systems that are coupled across a multiplicity of spatial and temporal that incorporate diverse physical processes.The contributors to this volume are both young researchers and renowned experts in space physics and astrophysics, applied mathematics, and computational physics. This volume describes the application of numerical methods and the algorithms themselves, allowing us to discuss the challenges that theory imposes on numerical schemes for solving partial differential equations describing collisional and collisionless processes in space and astrophysical plasmas.We would like to thank the participants who submitted their papers to Proceedings of ASTRONUM-2023 and especially to those who reviewed manuscripts thus ensuring the high quality of this publication. We also are grateful to Adele Corona (ICNSMeetings.com) for the excellent management of the conference.This publication will be useful to graduate and postgraduate students majoring in space physics, astrophysics, numerical, engineering, and applied mathematics. It is also aimed at specialists in applied mathematics and various fields of physics that involve flows of partially ionized plasmas at both the collisional and collisionless levels.Nikolai V. Pogorelov, Edouard Audit, and Gary P. ZankMarch 3, 2024

A 3D discrete model for soil desiccation cracking in consideration of moisture diffusion

Soil desiccation cracking is a common phenomenon on the earth surface. Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil. However, no three-dimensional (3D) model in the literature can consider the influence of desiccation cracking on moisture migration. To fill this gap, this work develops a novel 3D moisture diffusion discrete model that is capable of dynamically assessing the effect of cracking on moisture diffusion and allowing moisture to be discontinuous on both sides of the cracks. Then, the parametric analysis of the moisture exchange coefficient in the 3D moisture diffusion discrete model is carried out for moisture diffusion in continuous media, and the selection criterion of the moisture exchange coefficient for the unbroken cohesive element is given. Subsequently, an example of moisture migration in a medium with one crack is provided to illustrate the crack hindering effect on moisture migration. Finally, combining the 3D moisture diffusion discrete model with the finite-discrete element method (FDEM), the moisture diffusion-fracture coupling model is built to study the desiccation cracking in a strip soil and the crack pattern of a rectangular soil. The evolution of crack area and volume with moisture content is quantitatively analyzed. The modeling number and average width of cracks in the strip soil show a good consistency with the experimental results, and the crack pattern of the rectangular soil matches well with the existing numerical results, validating the coupled moisture diffusion-fracture model. Additionally, the parametric study of soil desiccation cracking is performed. The developed model offers a powerful tool for exploring soil desiccation cracking.

A New Approach to the Use of Non-Primitive Variables in the Mechanics of Continuous Media

The problem of an approximate solution to hydrodynamic problems is the consideration of pressure. To exclude it from the equations, the transition to “non-primitive variables” (vortex and velocity vector divergence) is made. In this case, there are difficulties in the algorithmization of new equations for solving the inverse problem of hydrodynamics and a lot of internal iterative calculations. The object of this study includes equations in “non-primitive” variables. The research methods are based on the transformation without simplifications and assumptions of hydrodynamic equations into a form containing “non-primitive” variables and the demonstration of the possibilities of solving the equations. The GAMS programming language was used for approximate solutions for the first time. The aim of this paper is to demonstrate the possibility of solving the full equations in “non-primitive” variables for various conditions. The results showed the possibility of considering the compressibility of the medium when solving the inverse problem of hydrodynamics; the identity of solutions of the proposed system of equations and equations using the potential; and the possibility of using optimizing programming languages for hydrodynamics problems. The scientific novelty of this research consists of solving the full equations of hydrodynamics with the use of “non-primitive” variables but without the use of the current function. Doi: 10.28991/ESJ-2024-08-02-021 Full Text: PDF

Physics of the Sub-Monolayer Lubricant in the Head-Disk Interface

This review presents a series of studies which have demonstrated that the diffusion characteristics of rarefied mobile lubricant films used in modern magnetic disks can be evaluated by a novel diffusion theory based on continuum mechanics, and that the meniscus force of the rarefied film is the major interaction force at the head-disk interface. The limitations of the conventional diffusion and disjoining pressure equations are first shown, and diffusion and disjoining pressure equations for rarefied liquid films are proposed, showing that the diffusion coefficient is in good agreement with the experiment. The experiment, in which glass spheres with radii of 1 and 2 mm collided with magnetic disks of different film thicknesses, showed that attraction similar to the pull-off forces of a static meniscus was measured only at the separation. Furthermore, mathematical analysis of the elastic meniscus contact between a sphere and a plane with a submonolayer liquid film showed that the maximum adhesion force is equal to the meniscus pull-off force and that the contact characteristics become similar to those of the JKR theory as the liquid film thickness decreases. A basic physical model of submonolayer liquid film is also proposed to justify the continuum mathematical equations.

Математическая модель процесса СВЧ и конвективной выпечки хлеба из сбивного теста

Whipped yeast-free bakery products require effective energy supply to dough in order to optimize energy consumption, baking time, and quality. This article introduces a verified mathematical model of microwave and convective baking for whipped bread based on heat and mass exchange equations.
 A full-scale experiment to verify the calculations involved dough samples with a humidity of 56 ± 1%. The samples underwent microwave and convective processing until the temperature in the crumb center reached 98 ± 1°C.
 The mathematical model was formalized as energy and mass conservation equations, which made it possible to consider baking as a non-stationary process of heat and mass transfer of moisture in an isotropic incompressible continuous medium in the diffusion approximation. The equation took into account the unstable phase transition boundary. The practical verification showed the mean error for microwave baking as 14.5% in temperature and 18.2% in moisture content. For convective baking, the results included 12.6% in temperature and 9.7% in moisture content. The mathematical model proved adequate to the real processes of heat and mass transfer. The error in calculating the temperature and moisture content fields was sufficient tooptimize the process.
 The physical and mathematical model of the baking process made it possible to evaluate the effect of technological variables on the temperature and moisture concentration fields in the dough samples. The mathematical model and the computational experiment can be used to identify static and dynamic characteristics of baking as an object of automatic control, i.e., to identify optimal control channels and actions, as well as to adjust the automatic control system to specific quality indicators.

Simulating earth deformation evolution caused by groundwater pumping through ordinary state-based Peridynamics method

Earth deformation including land subsidence and the related earth fissures caused by the over-exploitation of groundwater resources is threatening countries all over the World. At present, the simulation of earth deformation of aquifer system is mainly based on continuum and contact mechanics. These approaches lead to two main challenges, i.e. the need of knowing the location of possible earth fissures in advance and using meshes that must be adjusted during the rupture propagation. Here, ordinary state-based Peridynamics method is firstly introduced to simulate the evolution of continuous and discontinuous earth deformation due to groundwater withdrawal. A failure criteria accounting for shear and tensile strain simultaneously is proposed. The approach is used to simulate the evolution of land subsidence and earth fissures in compressible sedimentary soils with buried rigid ridges. Two case studies are reproduced: one is a test carried out in laboratory and the other one concerns Guangming village, Yangtze River delta. In both cases, the presence of a shallow buried bedrock crossing the alluvial deposits is responsible for the initiation and growth of earth fissure that a satisfactory captured by the model. For the lab experiment, a 0.1 m deep fissure appearing above the rocky tip is computed. In Guangming village area, results show that some small fissure groups were initiated. Then, three main earth fissures developed rapidly with the maximum depth of 32.5 m. This study proposes a consistency modelling framework to simulate continuum earth deformation and discontinuous fissures due to groundwater withdrawal in specific geological settings, and supply a reliable scientific tool for early warning of this geo-hazard.

A geometrically and thermodynamically compatible finite volume scheme for continuum mechanics on unstructured polygonal meshes

We present a novel Finite Volume (FV) scheme on unstructured polygonal meshes that is provably compliant with the Second Law of Thermodynamics and the Geometric Conservation Law (GCL) at the same time. The governing equations are provided by a subset of the class of symmetric and hyperbolic thermodynamically compatible (SHTC) models introduced by Godunov in 1961. Specifically, our numerical method discretizes the equations for the conservation of momentum, total energy, distortion tensor and thermal impulse vector, hence accounting in one single unified mathematical formalism for a wide range of physical phenomena in continuum mechanics, spanning from ideal and viscous fluids to hyperelastic solids. By means of two conservative corrections directly embedded in the definition of the numerical fluxes, the new schemes are proven to satisfy two extra conservation laws, namely an entropy balance law and a geometric equation that links the distortion tensor to the density evolution. As such, the classical mass conservation equation can be discarded. Firstly, the GCL is derived at the continuous level, and subsequently it is satisfied by introducing the new concepts of general potential and generalized Gibbs relation. The new potential is nothing but the determinant of the distortion tensor, and the associated Gibbs relation is derived by introducing a set of dual or thermodynamic variables such that the GCL is retrieved by dot multiplying the original system with the new dual variables. Once compatibility of the GCL is ensured, thermodynamic compatibility is tackled in the same manner, thus achieving the satisfaction of a local cell entropy inequality. The two corrections are orthogonal, meaning that they can coexist simultaneously without interfering with each other. The compatibility of the new FV schemes holds true at the semi-discrete level, and time integration of the governing PDE is carried out relying on Runge-Kutta schemes. A large suite of test cases demonstrates the structure preserving properties of the schemes at the discrete level as well.

Martensitic-like microstructures across the isostructural phase transitions in Cerium

The isostructural gamma–alpha phase transition in elemental cerium is an electronic transition caused by a delocalization of the 4f electrons. This affects the bonding properties of Ce atoms and leads to a large volume collapse reaching ∼17% in the low pressure regime (¡ 2 GPa). While great attention has been drawn on the electronic description of this transition, attempts to understand the mesoscale mechanisms of this structural transition and their consequences in terms of microstructure remain scarce. We have investigated this transition by means of combined X-ray Computed Tomography and Energy Dispersive X-ray Diffraction on polycrystalline samples. Our experimental observations reveal a platelet-shape microstructure across the transition and up to the critical point, which have been associated to displacive mechanisms. Based on continuum mechanics modeling and ab initio calculations, we propose that here, this microstructure is initiated by elastic instability and shear anisotropy in the ¡100¿ directions.

Forced vibrations of a cantilever beam using radial point interpolation methods: A comparison study

Meshless methods are a type of numerical method used to simulate continuum mechanics problems. These methods have been applied to several types of problems, there are a few works using meshless method focused on dynamic problems, but most works study static loading conditions. The current work aims at using two different meshless methods, the Radial Point Interpolation Method (RPIM) and the Natural Neighbours RPIM (NNRPIM), in a dynamic problem, specifically forced vibrations. This problem requires time integration, therefore three different time integration methods have also been tested, namely: the Central Difference Method (CDM), the Wilson method, and the Newmark method. The CDM is an explicit method, while the other two are implicit. A discretization study was performed to assess the ideal nodal discretization before the numerical and time integration methods are validated. For the implicit methods, different time step lengths were also tested. In the final example damping was introduced. The results prove the validity of the two meshless methods by having similar results to the Finite Element Method (FEM) using the three distinct time integration methods, different loading conditions, and damping.

An ordinary state-based peridynamic model for granular fracture in polycrystalline materials with arbitrary orientations in cubic crystals

Granular fracture holds significant implications in material mechanics. However, the previous studies in ordinary state-based peridynamic (OSB-PD) framework often neglect the internal crystalline structure of particles or only consider limited crystal orientation. To address this gap, a novel OSB-PD model for granular fracture within polycrystalline materials is proposed, in which the periodic functions are incorporated in the PD strain energy density, taking into account the inherent random orientation in cubic crystals. By comparing energy density from PD and the classical continuum mechanics, four PD material parameters are defined. Moreover, the corresponding surface correction method in the global coordinate system is also proposed. Several numerical examples including fracture analysis of polycrystalline materials are conducted to validate the effectiveness of the proposed method. The proposed ordinary state-based peridynamic model offers a fresh perspective for investigating granular fracture behaviors within polycrystalline materials.

Performance evaluation and parameter estimation of the advanced primary filtration (APF) process in wastewater treatment plants

Conventional technologies employed in wastewater treatment plants (WWTPs) demand significant energy consumption. Concurrently, the wastewater infrastructure is experiencing a heavy strain as a result of the increased influent loads and pollutants. Advanced primary filtration (APF) is an emerging wastewater treatment process for early removal of suspended solids from raw wastewater. In this work, the APF process comprises of a two-stage filtration system, consisting of a proprietary rotating belt filter (RBF) (collectively known as microsieve) followed by a proprietary continuous backwash upflow media filter (CBUMF). The principal focus of this study is the assessment of the APF process performance, and the prediction of the total suspended solids (TSS) effluent concentrations of the APF process, using a parameter estimation method. According to pilot scale experimental results, the percentages of TSS (average TSS removal rate of 51 %) and biological oxygen demand (BOD5) (average BOD5 removal rate of 30 %), removed by the microsieve were notably higher compared to conventional primary treatment (sedimentation). The removal efficiency of the APF process during stable operation, varied from 69 to 86 % for TSS, as compared to 50–70 % typically achieved with primary sedimentation. The removal performance of BOD5 varied from 44 to 82 %, as compared to 25 to 40 % typically achieved with primary sedimentation. The chemical oxygen demand (COD) removal rates for the APF process ranged between 62 and 90%, as compared to 25–40 % typically achieved with primary sedimentation. The early removal of TSS prior to aeration tank has the potential to significantly enhance the capacity of the WWTP and decrease the energy requirements of the aeration tank. A high degree of concordance between model predictions and experimental data was observed. This study demonstrated the potential of using the APF process for the early removal of TSS from raw municipal wastewater just upstream of the aeration tank.

Nonlinear bending of a soft slab subjected to vertical compression: A continuum mechanics model

The small bending behavior of linear elastic materials has been widespread in engineering in the history of mechanics. With the occurrence of soft materials, finite deformation bending is of great interest due to the high nonlinearity in large bending deformation. Previous theories primarily focus on the pure bending assumption, which is hard to achieve in practical bending experiments of soft materials because compressive forces cannot be neglected. In this paper, we propose a continuum mechanics-based nonlinear bending theory that incorporates an initial compression process to align with real-world experiments. We compare experimental data and simulation to our theoretical prediction to verify the accuracy of our theoretical model. The results demonstrated good agreement between our theory, experimental data, and finite element simulation. Furthermore, we compare our nonlinear bending theory with the classical Euler–Bernoulli theory to understand their respective behaviors better. This paper advances our understanding of bending phenomena by considering the effects of initial compression and incorporating a nonlinear approach. It provides valuable insights for practical applications of soft materials subjected to large bending deformation.

The principal bundle structure of continuum mechanics

In this paper it is shown that the structure of the configuration space of any continua is what is called in differential geometry a principle bundle. A principal bundle is a structure in which all points of the manifold (each configuration in this case) can be naturally projected to a manifold called the base manifold, which in our case represents pure deformations. All configurations projecting to the same point on the base manifold (same deformation) are called fibers. In this paper, it is shown that each of these fibers is then naturally isomorphic to the Lie group SE(3) representing pure rigid body motions. Furthermore, it will be shown that it is possible to define intrinsically (coordinate free), what is called a connection and this allows to split any continua motion in a rigid body sub-motion and a deformable one in a completely coordinate free way. As a consequence of that it is then possible to properly define a pure deformation space on which an elastic energy can be defined and this will be related to other literature on intrinsic strain which has not shown the geometric structure which will be presented in this work. This will be shown using screw theory and Lie groups. Screw theory is vastly used in the analysis of rigid body mechanisms but is not normally used to analyse continua. The paper will also relate known concepts of continua like helicity and enstrophy to screw theory concepts which will become evident by the presented construction.

Hubungan Dukungan Suami Dengan Kepatuhan Konsumsi Tablet Tambah Darah Pada Ibu Hamil di Wilayah Kerja Puskesmas Penanggalan Provinsi Aceh Tahun 2023

Anemia during pregnancy is still a global problem throughout the world. Prevention of anemia in pregnant women can be done by increasing compliance with the consumption of blood supplement tablets. Pregnant women need motivation and support from husband during pregnancy. This reseach aims to explore the relationship between husband’s support with compliance with the consumption of blood supplement tablets in the Puskemas Penanggalan Provinsi Aceh in 2023. This research uses a quantitative method with a cross sectional approach. Data analysis used the Chi Square methods. This research was conducted in the work area with a total of 52 pregant women with purposive sampling. The research are the majority of respondents with aged 26-35 years were 20 people (46,5%), the majority of pregnant women get husband’s support were 22 people (57,7%). The results of chi square test, p value = 0,003, there is a significant relationship between husband’s support with compliance consumes iron acid. Midwives are expected to be able to place more emphasis on counseling regarding nutritional intake during pregnancy by using the contents of my plate media, choosing simpler words and language to further optimize continuous educational media during counseling, so that pregnant women can more easily understand the counseling given and provide leaflets containing about the contents of my plate so that pregnant women can read and understand it

Innovative stearic acid-in-silicone oil (o/o) phase change material lubricating emulsions (PCMLEs): Thermo-rheological and tribological properties

This paper analyses the feasibility of using novel non-aqueous stearic acid-in-silicone oil (o/o) phase change material lubricating emulsions (PCMLEs). The novel use of these dispersions with heat storage capacity for lubricating applications can be considered a new approach since they have not yet been used for such purposes. In this study, PCMLEs consist of stearic acid, with a melting point of roughly 69 °C, as a dispersed phase change material in a continuous silicone oil medium. Samples were prepared by mixing different phase ratios, by high-shear processing and stabilised by a constant concentration of a silicone-based non-ionic surfactant. Taking into consideration the ability of stearic acid to absorb latent thermal energy during machinery operation, the potential application in lubrication has been assessed by means of stationary and temperature ramp friction tests. Moreover, the effect of the phase transition on the PCMLEs’ rheological response has been analysed through stationary flow tests and frequency sweeps within the linear viscoelastic range at constant temperatures, below (40 °C) and above (80 °C) the melting process of the disperse phase. Additionally, their thermal properties and morphology were also studied through X-ray diffraction measurements (XRD), differential scanning calorimetry (DSC) and polarised optical microscopy. As a result, the reported rheological properties and microstructure led to the enhancement in tribological characteristics of PCMLEs since a significant reduction in the friction factor is evidenced, within the whole temperature range, when compared to the silicone oil.

Study on three-dimensional model of ventilation drying and heat and mass transfer of bulk grain pile based on discrete-continuous media

Abstract In order to ensure the safety of grain storage and explore the mechanisms of water and heat transfer during the drying process of grain piles, this paper takes wheat as the research object, uses a thermal conductivity analyzer to measure the thermal conductivity and specific heat capacity of wheat, and obtains a linear relationship between the heat constant and water content of wheat. COMSOL software was used to establish a three-dimensional model of ventilation drying and heat and mass transfer of bulk grain piles based on discrete continuum media, which simulated the temperature and humidity changes during the drying process of the grain pile. The model was verified by a thin layer drying experiment. The results show that the simulated values of temperature and water content obtained by the wet heat transfer model are in good agreement with the experimental values, and the maximum errors are 2.14 % and 5.68 % respectively. During the drying process, the grain temperature of wheat at the bottom of the grain pile increased rapidly, compared with that at the top of the grain pile, and the temperature of the wheat at the center was higher than that at the edge. At the end of drying, the moisture content from highest to lowest was top edge > top center > bottom edge > bottom center. Therefore, the model can be used to further study the changes of grain pile temperature gradient and water gradient.

A temporary soil dump settlement and landslide risk analysis using the improved small baseline subset-InSAR and continuous medium model

Abandoned soil disposal in China has become increasingly challenging, which may pose significant safety hazards such as soil settlement and landslides. Interferometry Synthetic Aperture Radar (InSAR) is effective in surface deformation monitoring and Small Baseline Subset-InSAR (SBAS-InSAR) can obtain sufficient coherent point density from the bare soil surface. This study investigated Chishi soil dump in the Shenzhen-Shanwei Special Cooperation Zone (SSSCZ), and a total of 91 Sentinel-1 images from 2019 to 2022 was processed. Accordingly, an improved SBAS-InSAR method was utilized to analyze the soil dump’s time-series deformation, and multi-source remote sensing data were used for auxiliary interpretation. Our results indicate that precipitation, high temperature, and construction vibrations may cause instability of the soil dump. Therefore, a depth-integrated continuous medium model was introduced to analyze the potential landslide risk of the soil dump, which demonstrate that a landslide will likely occur, harm personnel, and damage the buildings surrounding the Chishi soil dump when it was saturated (λ ≥ 0.50). This research can provide a vital case reference for the analysis, interpretation, disaster prevention, and control evaluation of similar soil dumps.