Variation Of Potential Energy Research Articles

Melting phenomena of Cu0.25 Ni0.75 bimetallic alloy: A molecular dynamics approach

Alloys of transition metals draw attention from the scientific community due to the interesting physical and thermal behaviour they exhibit over their pure metal components. Atomic Molecular Dynamics Simulations on Pure copper (Cu) metal, nickel (Ni) metal and their Ni rich alloy (Cu0.25 Ni0.75) have been carried out using the second nearest neighbour modified embedded atom potential parameters to investigate on the melting phenomena of the Ni rich alloy. The variation of average potential energy with respect to temperature is used to estimate the melting point temperature. Various other analyses such as; specific heat, mean square displacement of atoms and self-diffusion coefficients of atoms have been calculated in order to determine the exact transition region in the metals and to mark the melting point temperatures. The results show that the melting temperature of the Ni rich alloy is more as compared to its pure components (Cu and Ni). For the alloy, the calculated melting temperature is 2430 K± 5 K, whereas that of the pure Cu metal is found to be 1900 K± 5 K and pure Ni metal is 2370 K± 5 K. The study shows that the alloy under investigation is comparatively more thermally stable than pure Cu and Ni.

ANALYTICAL SOLUTION FOR NONLINEAR INTERACTION OF EULER BEAM RESTING ON A TENSIONLESS SOIL

The nonlinear interaction between an elastic Euler beam and a tensionless soil foundation is studied. Exact analytical solutions of the challenging problem are rather complicated. The basic obstacle is imposing compatibility conditions at lift-off points. These points are determined as a part of the solution although being needed to get the solution itself. In the current work, solutions are derived using the approximate Rayleigh-Ritz method. The principal of vanishing variation of potential energy is adopted. The solution is approximated using a set of suitable trial functions. Lift-off points are identified through an iterative procedure and compatibility conditions are satisfied implicitly. Results are presented for various cases, including clamped support and free end condition. Various distributed loading conditions are analyzed. Exact solutions are revised briefly. Accurate high order approximate analytical solutions are obtained using MAXIMA symbolic manipulator. The convergence of approximate solutions towards the exact solutions is verified. For each case detailed results of deflection, bending moment and shear are presented.

A molecular dynamics study on tensile and low cycle fatigue behaviors of Ti single crystal nanowire

It is essential to reveal the fatigue mechanism of the main elements in alloys at the nano scale for the material design against fatigue failure. In the present study, molecular dynamics (MD) simulations have been employed to investigate the static tensile and low cycle fatigue (LCF) behaviors of a defect free single crystal Ti nanowire with hexagonal close-packed (HCP) structure at room temperature (300 K). Results showed that the explosive initiations of body centered cubic and disordered atoms led yielding of Ti nanowire under static tensile load. The following stress response to constant amplitude cyclic strain was found strongly relatived to the instantaneous microstructure configuration at the first unloading. Variation of potential energy was used to characterize the competitions between face-centered cubic (FCC) atoms, body-centered cubic (BCC) atoms and disordered atoms. A conclusion was drew that the cyclic characteristics of Ti nanowire were heavily dependent on the dominant atom configuation during the fatigue process. Additionally, this research also found that static tensile yield strength of Ti nanowire may vary notably with respect to crystal direction, e.g. for [100] (or for [0001]) it is about 1.5 times of that for [110].

Electrostatic Circular Membrane MEMS: An Approach to the Optimal Control

The recovery of the membrane profile of an electrostatic micro-electro-mechanical system (MEMS) is an important issue, because, when an external electrical voltage is applied, the membrane deforms with the risk of touching the upper plate of the device producing an unwanted electrostatic effect. Therefore, it is important to know whether the movement admits stable equilibrium configurations especially when the membrane is closed to the upper plate. In this framework, this work analyzes the behavior of a two-dimensional (2D) electrostatic circular membrane MEMS device subjected to an external voltage. Specifically, starting from a well-known 2D non-linear second-order differential model in which the electrostatic field in the device is proportional to the mean curvature of the membrane, the stability of the only possible equilibrium configuration is studied. Furthermore, when considering that the membrane is equipped with mechanical inertia and that it must not touch the upper plate of the device, a useful range of possible values has been obtained for the applied voltage. Finally, the paper concludes with some computations regarding the variation of potential energy, identifying some optimal control conditions.

C-Legged Hexapod Robot Design Guidelines Based on Energy Analysis

C-legged hexapod robots offer a balanced trade-off between the robust stability of wheeled robots and the increased-motion capabilities of legged robots, and therefore, are currently of great interest. This article investigates the impact of mass, leg radius, and angular velocity on the energy consumption of C-legged hexapod robots, in order to develop a set of design guidelines that maximize the robot’s performance. The kinematic model of a single C-leg system is obtained and used to determine the system’s energy consumption associated with gravitational potential energy (GPE) and kinetic energy (KE) variations. Both the kinematic model and energy model are validated in a custom-made test bench. Our results show that the kinematic model very accurately predicts the trajectory of the system in space, but due to the varying load experienced by the motor, the system lags compared to the model predictions. Furthermore, the energy model has been also validated experimentally and successfully predicts the motor consumption periods. Using the energy model, it has been concluded that the angular velocity of the leg and the leg radius have an exponential relationship with motor peak power demand—directly affecting the motor selection. On the other hand, the mass is inversely proportional to the robot efficiency, and therefore, must be kept as low as possible.

A 2D Membrane MEMS Device Model with Fringing Field: Curvature-Dependent Electrostatic Field and Optimal Control

An important problem in membrane micro-electric-mechanical-system (MEMS) modeling is the fringing-field phenomenon, of which the main effect consists of force-line deformation of electrostatic field E near the edges of the plates, producing the anomalous deformation of the membrane when external voltage V is applied. In the framework of a 2D circular membrane MEMS, representing the fringing-field effect depending on |∇u|2 with the u profile of the membrane, and since strong E produces strong deformation of the membrane, we consider |E| proportional to the mean curvature of the membrane, obtaining a new nonlinear second-order differential model without explicit singularities. In this paper, the main purpose was the analytical study of this model, obtaining an algebraic condition ensuring the existence of at least one solution for it that depends on both the electromechanical properties of the material constituting the membrane and the positive parameter δ that weighs the terms |∇u|2. However, even if the the study of the model did not ensure the uniqueness of the solution, it made it possible to achieve the goal of finding a stable equilibrium position. Moreover, a range of admissible values of V were obtained in order, on the one hand, to win the mechanical inertia of the membrane and, on the other hand, to ensure that the membrane did not touch the upper disk of the device. Lastly, some optimal control conditions based on the variation of potential energy are presented and discussed.

Theoretical study of the catalytic effect of TM-C4H4 and TM-C5H5 (TM = Cr, Ti, V, Sc) on the activation of O2 at the cathode and CH3OH at the anode in “CH3OH-O2″ fuel cell via DFT computational method

The study of the interaction of oxygen molecule with organometallic compounds containing transition metals has always been an interesting subject for research, as the O2 activation by them is a measure of the efficiency of organometallic catalysts. This study examined the catalytic effect of some organometallic compounds containing transition metals with the general formula of TM-CmHm on increasing the reaction rate of “methanol-oxygen” fuel cell using the method of density functional theory (DFT) and PW91 method as well as the basis set of 6-31G(d) (TM represents each of Sc, Ti, V and Cr and m is equal to 4 or 5). The structures of the mentioned compounds were optimized by the natural bonding orbital calculations (NBO). Then, the diagrams of the density state (DOS) were plotted for them and afterward, gap energy (Eg), chemical hardness (η) ، chemical potential (µ) and electrophilicity (ω) were calculated in each case. The Eg and η of ScC5H5 were smaller than that of the others, indicating greater reactivity. Theoretical calculations showed that each of the TMs in TM-CmHm had a partial negative electric charge, which was higher in ScC5H5 than in others causing higher chemical activity. The adsorption energies of O2 and CH3OH were calculated and reported on each of the TM-CmHm. The adsorption energy of O2 and CH3OH on ScC5H5 was more negative than that of the other TM-CmHm used. This confirms that the compound had a greater efficiency and ability to play a catalytic role in the “oxygen - methanol” fuel cell. The results showed that the bond length of O=O increased by about 24% on average due to its adsorption on ScC5H5. The O-H bond length was significantly increased in response to the methanol adsorption process on ScC5H5. Increasing the bond length caused instability of the bond and raising its chemical activity and reactivity. The adsorption kinetics of each of O2 and CH3OH on ScC5H5 were also studied by the above-computational method. The potential energy variation of the “adsorbate/adsorbent” system in terms of reaction coordinate (bond length of O=O or O-H) in each case was evaluated with a one transition state observed in each case.

Thermo-mechanical buckling of stepped circular bi-laminates

Thermo-mechanical buckling of stepped circular bi-laminates subjected to a uniform temperature field is investigated analytically. The governing equations are derived via the Principal of Stationary Potential Energy, resulting in self-consistent constitutive equations of the composite structure, as well as the equations of motion and the associated matching and boundary conditions for the composite structure. A loading parameter is identified, and closed form analytical solutions to the non-linear problem are obtained, yielding exact results within the context of the formulation. A stability criterion is established based on the second variation of the total potential energy of the system in order to identify regions of stable and unstable equilibrium configurations, and a critical temperature and a critical membrane force are determined. Simulation results based on the analytical solutions are generated and a critical and characteristic behavior is assessed for both clamped-fixed supports and hinged-fixed supports conditions. The phenomenon of “sling-shot buckling” is observed. Results of parameter studies are also presented, which demonstrate the influence that material and geometric parameters of the system have on critical behavior. In particular, thermal expansion coefficient ratio, modulus ratio and thickness ratio all play a non-trivial role in the temperature carrying capacity of the structure for relatively large patches. Because the loading parameters and geometric parameters appear explicitly in the analytical solution and simulations, the model and results will be useful towards the design of micro-electromechanical systems, smart structures and related configurations.

Constant twist rate response of symmetric and asymmetric Σ5 aluminium tilt grain boundaries: molecular dynamics study of deformation processes

Room temperature torsional deformation behaviour of bicrystal aluminium specimens (corresponding to Σ5 family) is studied by the application of constant twist rate using molecular dynamics simulations by employing the (embedded atom method) EAM potential. To simulate the torsional loading, periodic boundary condition is employed in x-direction, whereas shrink-wrapped boundary condition is applied in y- and z-directions. A constant twist rate of 1°/ps has been applied at either end of the samples in opposite directions. The variation of potential energy as a function of relative rotation between the ends of the specimen is recorded. The evolution of different types of dislocation and characteristics behaviour due to interactions among dislocations during deformation has been analysed. The populations of Shockley partial dislocations, dislocation loops, dislocation locks, and dislocation junctions increase as the torsional deformation progresses. The structural variations occurred in the specimen are explained with the aid of defect evolutions (such as vacancies population and amorphous atoms percentage as a function of torsion angle), and the grain boundary migration and grain rotation processes are described with atomic snapshots. Additionally, we have tried to correlate trends between grain boundary energy and various deformation mechanisms.

Simulated Atmospheric Response to Four Projected Land-Use Land-Cover Change Scenarios for 2050 in the North-Central United States

AbstractLand-use land-cover change (LULCC) has become an important topic of research for the central United States because of the extensive conversion of the natural prairie into agricultural land, especially in the northern Great Plains. As a result, shifts in the natural climate (minimum/maximum temperature, precipitation, etc.) across the north-central United States have been observed, as noted within the Fourth National Climate Assessment (NCA4) report. Thus, it is necessary to understand how further LULCC will affect the near-surface atmosphere, the lower troposphere, and the planetary boundary layer (PBL) atmosphere over this region. The goal of this work was to investigate the utility of a new future land-use land-cover (LULC) dataset within the Weather Research and Forecasting (WRF) modeling system. The present study utilizes a modeled future land-use dataset developed by the Forecasting Scenarios of Land-Use Change (FORE-SCE) model to investigate the influence of future (2050) land use on a simulated PBL development within the WRF Model. Three primary areas of LULCC were identified within the FORE-SCE future LULC dataset across Nebraska and South Dakota. Variations in LULC between the 2005 LULC control simulation and four FORE-SCE simulations affected near-surface temperature (0.5°–1°C) and specific humidity (0.3–0.5 g kg−1). The differences noted in the temperature and moisture fields affected the development of the simulated PBL, leading to variations in PBL height and convective available potential energy. Overall, utilizing the FORE-SCE dataset within WRF produced notable differences relative to the control simulation over areas of LULCC represented in the FORE-SCE dataset.

A Sparse Optimization-Based Control Method for Manipulator With Simultaneous Potential Energy Minimization

Manipulators may often endure large-scale potential energy variations during kinematic control, producing unsafe oscillations of posture-hold effects. In this brief, for the first time, a sparse-optimization-based control method is proposed to simultaneously guarantee task accuracy and reduce potential energy variations for manipulators. The proposed control approach is formulated as an $L_{p}$ -norm sparse optimization paradigm with the variation of the potential energy as the constraint. Simulation results on the $n$ -link planar manipulator and experiment results on a 6-DoF manipulator system verify the proposed control method for accurate motion control tasks with potential energy minimization, with the average potential energy variations of the manipulators largely diminished with the sparse kinematic resolutions.

Mechanism of C60 rotation and translation on hexagonal boron-nitride monolayer.

Newly synthesized nanocars have shown great potential to transport molecular payloads. Since wheels of nanocars dominate their motion, the study of the wheels helps us to design a suitable surface for them. We investigated C60 thermal diffusion on the hexagonal boron-nitride (h-BN) monolayer as the wheel of nanocars. We calculated C60 potential energy variation during the translational and rotational motions at different points on the substrate. The study of the energy barriers and diffusion coefficients of the molecule at different temperatures indicated three noticeable changes in the C60 motion regime. C60 starts to slide on the surface at 30 K-40 K, slides freely on the boron-nitride monolayer at 100 K-150 K, and shows rolling motions at temperatures higher than 500 K. The anomaly parameter of the motion reveals that C60 has a diffusive motion on the boron-nitride substrate at low temperatures and experiences superdiffusion with Levy flight motions at higher temperatures. A comparison of the fullerene motion on the boron-nitride and graphene surfaces demonstrated that the analogous structure of the graphene and hexagonal boron-nitride led to similar characteristics such as anomaly parameters and the temperatures at which the motion regime changes. The results of this study empower us to predict that fullerene prefers to move on boron-nitride sections on a hybrid substrate composed of graphene and boron-nitride. This property can be utilized to design pathways or regions on a surface to steer or trap the C60 or other molecular machines, which is a step toward directional transportation at the molecular scale.

Mechanistic pathway of water adsorption to impact on the nonlinear elasticity of single-crystalline ZnO NWs

Surface modification via adsorbates is significant for property prediction in nanostructures where surface effect is dominant. This is especially vital for zinc oxide (ZnO) nanowires (NWs) which has no native passivation layer. As water is an ubiquitous environmental factor and its aggregation on ZnO surface is favoured, molecular statics (MS) simulations are used to study the deformation of ZnO with surface water adsorption in the finite strain regime (up to 0.1). Three types of water covered surface structures are considered to examine their effects on the size-dependence of linear (Y0) and nonlinear (Y1) elastic moduli. The pathway of adsorption to impact NWs is identified by revealing the radial distribution of Y0, Y1 and residual stress for the NWs. The physical origins of the water adsorption effects are further discussed in terms of the layer-wise equilibrium structure and potential energy variation.

Crustal Stress State in Taiwan: Moderately Strong Crust Supporting Gravitational and Flexural Loading

AbstractIn Taiwan and other contractional tectonic wedges, there is evidence that the basal detachment is very weak and the overlying crust is relatively strong. In this study, we compute the absolute deviatoric 3‐D stress field in Taiwan using focal mechanism data and coseismic stress changes for the 1999 M7.6 Chi‐Chi earthquake. We estimate a minimum coefficient of friction of 0.3 in the upper 15 km crust, assuming hydrostatic pore pressure, consistent with a moderately strong crust. The estimated stress state is consistent with primary tectonic structures of Taiwan. The maximum compressive stress in the fold and thrust belt and the Coastal Range is approximately aligned with relative motion of the Eurasian and the Philippine Sea Plates, but the minimum and intermediate principal stresses vary laterally and with depth. A reverse‐faulting stress regime wraps around the Peikang high in western Taiwan suggesting inherited basement structure influences crustal stress state. Vertical maximum compressive stress is inferred under the high topography of the Central Range mountains. We present a simple stress model for Taiwan assuming spatial variations in gravitational potential energy are supported elastically. The model stress state is broadly consistent with the stress inversion result. The model shows that vertical maximum compressive stress in the Central Range is a result of high topography and thick crustal root. Consistent with a moderately strong crust, the model deviatoric stresses in areas of high seismicity in Taiwan are of the order 50–100 MPa. Lower deviatoric stresses under the Central Range are consistent with low rates of observed seismicity.

The Seismic Electromagnetic Emissions During the 2010 Mw 7.8 Northern Sumatra Earthquake Revealed by DEMETER Satellite

The abnormal electromagnetic emissions recorded by the DEMETER satellite associated with the April 6, 2010 Mw 7.8 northern Sumatra earthquake are examined in this study. The variations of wave intensities recorded by revisiting orbits from August 2009 to May 2010 indicate that some abnormal enhancements at ELF (Extremely Low Frequency) range of 300 - 800 Hz occurred from 10 to 3 days before the main shock, while they remained a relatively smooth trend during quiet seismic activity times. The perturbation amplitudes relative to the background map which were built by using the same-time seasonal window (February 1 to April 30) data from 2008 to 2010 further suggested strong enhancements of wave intensities during the period prior to the earthquake. We computed the wave propagation parameters for the electromagnetic field waveform data by using the Singular Value Decomposition method, and results show that there are certain portions of the ELF emissions obliquely propagating upward from the Earth towards outer space direction at 10 and 6 days before the main shock. The potential energy variation of acoustic-gravity wave (AGW) suggests the possible existence of AGW stability with wavelengths roughly varying from 5.45 to 9.49 km in atmosphere at the time of the main shock. In this study, we comprehensively investigate the link between the electromagnetic emissions and the earthquake activity through a convincing observational analysis, and preliminarily explore the seismic-ionospheric disturbance coupling mechanism, which is still not fully understood at present by the scientific community.

A Newton solver for micromorphic computational homogenization enabling multiscale buckling analysis of pattern-transforming metamaterials

Mechanical metamaterials feature engineered microstructures designed to exhibit exotic, and often counter-intuitive, effective behaviour such as negative Poisson’s ratio or negative compressibility. Such a specific response is often achieved through instability-induced transformations of the underlying periodic microstructure into one or multiple patterning modes. Due to a strong kinematic coupling of individual repeating microstructural cells, non-local behaviour and size effects emerge, which cannot easily be captured by classical homogenization schemes. In addition, the individual patterning modes can mutually interact in space as well as in time, while at the engineering scale the entire structure can buckle globally. For efficient numerical predictions of macroscale engineering applications, a micromorphic computational homogenization scheme has recently been developed (Rokoš et al., J. Mech. Phys. Solids 123, 119–137, 2019). Although this framework is in principle capable of accounting for spatial and temporal interactions between individual patterning modes, its implementation relied on a gradient-based quasi-Newton solution technique. This solver is suboptimal because (i) it has sub-quadratic convergence, and (ii) the absence of Hessians does not allow for proper bifurcation analyses. Given that mechanical metamaterials often rely on controlled instabilities, these limitations are serious. Addressing them will reduce the dependency of the solution on the initial guess by perturbing the system towards the correct deformation when a bifurcation point is encountered. Eventually, this enables more accurate and reliable modelling and design of metamaterials. To achieve this goal, a full Newton method, entailing all derivations and definitions of the tangent operators, is provided in detail in this paper. The construction of the macroscopic tangent operator is not straightforward due to specific model assumptions on the decomposition of the underlying displacement field pertinent to the micromorphic framework, involving orthogonality constraints. Analytical expressions for the first and second variation of the total potential energy are given, and the complete algorithm is listed. The developed methodology is demonstrated with two examples in which a competition between local and global buckling exists and where multiple patterning modes emerge. The numerical results indicate that local to global buckling transition can be predicted within a relative error of 6% in terms of the applied strains. The expected pattern combinations are triggered even for the case of multiple patterns.

Atmospheric Precipitation and Anomalous Upper Mantle in Relation to Intraplate Seismicity in Norway

AbstractTwo enigmatic regions of high intraplate seismicity in Norway (Western Norway and the Nordland area) show a temporal correlation between the number of earthquakes within the upper crystalline crust and intensity of rain and snowmelt at the Earth's surface. This correlation is obvious in the Nordland area where detailed and reliable data on seismicity are available, whereas the correlation is weaker in Western Norway where detailed data on seismicity are missing. Moreover, these discrete zones of high seismic activity coincide spatially with prominent, low‐velocity, and, most likely, thermally anomalous zones in the upper mantle. We propose that in addition to other causes, the high seismicity may be controlled by the anomalous upper mantle, along with topographically induced gravitational potential energy and crustal density variations. Precipitation‐induced, seasonal increases in pore‐fluid pressure within the fractured crystalline bedrock and changes in water loads may modulate the tectonically controlled seismicity.

Probing effects of thermal and chemical coupling method on decomposition of methane hydrate by molecular dynamics simulation

Methane hydrate, being a potential alternative energy source has attracted the attention of many researchers. Here, we investigated the decomposition of methane hydrate with and without alcohols at different temperatures. The results showed that the hydroxyl group of alcohol molecules close to methane hydrate tends to reorient toward methane hydrate. The formation of hydrogen bonds between alcohol and water in methane hydrate cages destabilises the (methane hydrate) structure, thus leading to its decomposition. We also studied the effects of temperature on alcohols used during methane hydrate decomposition by comparing the variations in total potential energy with temperature. We observed that 300 K is the turning point, when the temperature is lower than 300 K, the accelerating effect of alcohol on methane hydrate decomposition is more pronounced. Additionally, the effect of temperature was found to vary with alcohols. For methanol, temperature mainly affects the rate of diffusion; a high rate of diffusion accelerates the decomposition of methane hydrate. For glycerol, temperature mainly affects the interaction energy between glycerol and water, which can accelerate the decomposition of methane hydrate. Our work provides a theoretical basis for future researches into exploitation of methane hydrate by combining thermal stimulation and alcohol.

Zeroing dynamics method for motion control of industrial upper-limb exoskeleton system with minimal potential energy modulation

Abstract Accurate motion control of industrial upper-limb exoskeleton can provide efficient assistance for subjects to perform various industrial manipulation tasks. In most motion control scenarios of upper-limb exoskeletons, the variations of potential energy frequently reach to a high level of oscillations, leading to the reconstructed motion uncomfortable or dangerous. In this paper, in order to achieve minimal potential energy variation and accurate motion control of the upper-limb exoskeleton, we propose a novel motion planning strategy with minimal potential energy modulation. Such motion resolution scheme is formulated as an optimization problem and solved by the zeroing dynamics (ZD) to achieve elegant global convergence. Simulation and experiment results show that the potential energy variation range of the upper-limb exoskeleton can be significantly decreased by average 99.34 % in both X-Y and X-Z planes, in addition to finishing tracking the desired motion path accurately. All of these demonstrate that the efficiency and superiority of the proposed method for potential energy minimization during achieving accurate motion planning and control.

Stress and deformation mechanisms at a subduction zone: insights from 2-D thermomechanical numerical modelling

SUMMARY Numerous processes such as metamorphic reactions, fluid and melt transfer and earthquakes occur at a subducting zone, but are still incompletely understood. These processes are affected, or even controlled, by the magnitude and distribution of stress and deformation mechanism. To eventually understand subduction zone processes, we quantify here stresses and deformation mechanisms in and around a subducting lithosphere, surrounded by asthenosphere and overlain by an overriding plate. We use 2-D thermomechanical numerical simulations based on the finite difference and marker-in-cell method and consider a 3200 km wide and 660 km deep numerical domain with a resolution of 1 km by 1 km. We apply a combined visco-elasto-plastic deformation behaviour using a linear combination of diffusion creep, dislocation creep and Peierls creep for the viscous deformation. We consider two end-member subduction scenarios: forced and free subduction. In the forced scenario, horizontal velocities are applied to the lateral boundaries of the plates during the entire simulation. In the free scenario, we set the horizontal boundary velocities to zero once the subducted slab is long enough to generate a slab pull force large enough to maintain subduction without horizontal boundary velocities. A slab pull of at least 1.8 TN m–1 is required to continue subduction in the free scenario. We also quantify along-profile variations of gravitational potential energy (GPE). We evaluate the contributions of topography and density variations to GPE variations across a subduction system. The GPE variations indicate large-scale horizontal compressive forces around the trench region and extension forces on both sides of the trench region. Corresponding vertically averaged differential stresses are between 120 and 170 MPa. Furthermore, we calculate the distribution of the dominant deformation mechanisms. Elastoplastic deformation is the dominant mechanism in the upper region of the lithosphere and subducting slab (from ca. 5 to 60 km depth from the top of the slab). Viscous deformation dominates in the lower region of the lithosphere and in the asthenosphere. Considering elasticity in the calculations has an important impact on the magnitude and distribution of deviatoric stress; hence, simulations with increased shear modulus, in order to reduce elasticity, exhibit considerably different stress fields. Limiting absolute stress magnitudes by decreasing the internal friction angle causes slab detachment so that slab pull cannot be transmitted anymore to the horizontal lithosphere. Applying different boundary conditions shows that forced subduction simulations are stronger affected by the applied boundary conditions than free subduction simulations. We also compare our modelled topography and gravity anomaly with natural data of seafloor bathymetry and free-air gravity anomalies across the Mariana trench. Elasticity and deviatoric stress magnitudes of several hundreds of MPa are required to best fit the natural data. This agreement suggests that the modelled flexural behaviour and density field are compatible with natural data. Moreover, we discuss potential applications of our results to the depth of faulting in a subducting plate and to the generation of petit-spot volcanoes.