Forces in mechanics最新文献_第10页

Analysis of Jeffrey fluid on MHD flow with stretching – porous sheets of heat transfer system 杰弗里流体对传热系统多孔板拉伸MHD流动的分析

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100180

D Thenmozhi , M. Eswara Rao , RLV. Renuka Devi , Ch. Nagalakshmi

引用次数: 1

Research on the Sliding Mode – PID control algorithm tuned by fuzzy method for vehicle active suspension 汽车主动悬架滑模- PID模糊整定控制算法研究

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100206

Tuan Anh Nguyen

{"title":"Research on the Sliding Mode – PID control algorithm tuned by fuzzy method for vehicle active suspension","authors":"Tuan Anh Nguyen","doi":"10.1016/j.finmec.2023.100206","DOIUrl":"10.1016/j.finmec.2023.100206","url":null,"abstract":"<div><p>The road surface's roughness is the primary source of vehicle oscillations when in motion. An active suspension is employed to enhance road holding, ride comfort, and stability. This research studies a dynamics model with 5 state variables to simulate vehicle oscillations based on four excitation scenarios from the road surface. In each instance, four distinct circumstances were discovered. Besides, the complicated control solution for an active suspension was created by this research, and it is called SMPIDF (Sliding Mode – PID tuned by Fuzzy). This is an entirely innovative algorithm with several significant benefits. The system's ultimate control signal is synthesized from the signals of the linear controller PID (Proportional – Integral – Derivative) and the nonlinear controller SMC (Sliding Mode Control). The defined fuzzy rule will continually alter the controller's settings. The simulation findings indicate that the acceleration and displacement of a car body are drastically decreased when an active suspension is managed to utilize the SMPIDF algorithm. The displacement and acceleration values do not surpass twenty percent and eighty percent, respectively, when compared to a car using a standard passive suspension. In addition, the characteristic of \"chattering\" does not occur when the controllers are combined. The overall effectiveness of this algorithm is rather significant. This approach applies to increasingly complicated models.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44566288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Preliminary evaluation of the climate-induced fatigue in wood: A physical and computational approach 木材气候疲劳的初步评价：一种物理和计算方法

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100186

A. Califano , A. Zanola , I. Di Terlizzi , M. Baiesi , C. Bertolin

{"title":"Preliminary evaluation of the climate-induced fatigue in wood: A physical and computational approach","authors":"A. Califano , A. Zanola , I. Di Terlizzi , M. Baiesi , C. Bertolin","doi":"10.1016/j.finmec.2023.100186","DOIUrl":"10.1016/j.finmec.2023.100186","url":null,"abstract":"<div><p>Wood is the organic hygroscopic material for excellence. Due to its extremely easy handling, it has always been used in many applications, especially as building material for artefacts and works of art. However, it is highly climate-susceptible as it swells or shrinks by exchanging moisture with the surrounding environment when natural or artificial microclimatic fluctuations occur. The shrinkage/swelling of wood, if repeated over time, may cause the arising of deformations or damage that may lead to catastrophic failures. For this reason, in this work, a preliminary study about the effect that repeated microclimatic loads have on wooden samples is carried out. To do so, well-established fatigue approaches have been implemented, with few simplifying considerations. The case study is a slice of <em>Scots pine</em> which is assumed to be stored inside Ringebu stave church (Norway). Ringebu indoor microclimate is reconstructed, through a proper transfer function, starting from outdoor temperature data downloaded from web platforms. The reconstructed indoor temperature timeseries cover three periods: far past (1948–1977), recent past (1981–2010) and far future (2071–2100). The results obtained for the three periods made it possible to gain insights about the climate-induced fatigue of wood and to preliminary assess the impact of climate change. It has been observed that successive similar temperature fluctuations can be potentially treated as a block of constant amplitude and constant frequency fatigue-like load. Finally, introducing few simplifying considerations, it has been assessed that the simulated behavior is coherent with the theoretical one coming from exploiting well-established thermo-based methods.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48126659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Stress analysis of the contact problem in a functionally graded layer loaded with a distributed load and two rigid circular punches resting on an elastic two quarter planes 弹性四分之二平面上分布载荷和两个刚性圆形冲头作用下梯度层接触问题的应力分析

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100203

Fatih Kaya, Alper Polat

{"title":"Stress analysis of the contact problem in a functionally graded layer loaded with a distributed load and two rigid circular punches resting on an elastic two quarter planes","authors":"Fatih Kaya, Alper Polat","doi":"10.1016/j.finmec.2023.100203","DOIUrl":"10.1016/j.finmec.2023.100203","url":null,"abstract":"<div><p>In this study, the solution of the contact problem in a functionally graded (FG) layer resting on elastic two quarter planes was done using the finite element method (FEM). The contact problem consists of two rigid circular punches loaded FG and two elastic quarter planes. P and Q loads are transmitted to the FG layer by two rigid circular punches. All surfaces in the problem were considered as frictionless and the weight effect is also taken into account. The two-dimensional model of the contact problem was created with the ANSYS package program based on FEM and the stress analyzes were performed. All operations of quarter planes and circular punches are done with standard ANSYS menus. However, defining the material properties of the FG layer and dividing into meshes in finite elements cannot be done with standard menus. For this reason, a special macro was added to the program in order to define the material properties of the FG layer and to perform the mesh division, and the necessary parameters were applied to the layer by this macro. In the study, the effects of external load, stiffness parameter (βh), density parameter (γh) and contact stresses of distributed load change, normal stresses, and stresses along the depth were investigated.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49089387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Buckling behaviour of dual-thickness dished shells under uniform pressure 均匀压力下双层碟形壳体的屈曲行为

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100174

Surya Mani Tripathi , R. Muthukumar , S Anup

{"title":"Buckling behaviour of dual-thickness dished shells under uniform pressure","authors":"Surya Mani Tripathi , R. Muthukumar , S Anup","doi":"10.1016/j.finmec.2023.100174","DOIUrl":"10.1016/j.finmec.2023.100174","url":null,"abstract":"<div><p>The dual thickness dished shells are made of conical frustum with a closed stiff top at the smaller diameter end of the frustum. The dished shells are categorized as dual-thickness because of higher thickness of the top circular region than that of the conical region. The higher thickness of top flat circular portion makes this more stiffer. The buckling behaviour of these shells is similar to that of arches, spherical caps and shallow conical frustums. The variation in curvature of these shells and different stiffnesses of the conical and top circular region makes them very interesting and innovative. Making the top circular region stiffer avoids the need for stiff support in the top circular region for practical applications under uniform pressure. In the present study, a nonlinear finite element analysis on metallic dished shells of dual-thickness is attempted by varying different geometrical parameters such as thickness of conical region, height and top flat region radius of the shell under uniform pressure. This parametric analysis is carried out to find out the effect of elastic and elastic-perfectly-plastic material properties, boundary conditions and imperfection sensitivity of Eigen-mode type axisymmetric imperfections on the critical buckling pressure. It is found that material plasticity has a significant effect on the critical buckling pressure of dual-thickness dished shells. The effect of the axisymmetric Eigen-mode imperfections on critical buckling pressure is significant for the elastic material model and very small with elastic-perfectly-plastic material models. The information collected from the current study can be used for the detailed design of dual thickness dished shells.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48751080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study of transient analysis of a conductive beam carrying an electrical current subjected to magnetic field with elastically restrained ends 端部受弹性约束的导电梁在磁场作用下的瞬态分析研究

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100178

Elham Tahmasebi , Nariman Ashrafi Khorasani

{"title":"Study of transient analysis of a conductive beam carrying an electrical current subjected to magnetic field with elastically restrained ends","authors":"Elham Tahmasebi , Nariman Ashrafi Khorasani","doi":"10.1016/j.finmec.2023.100178","DOIUrl":"10.1016/j.finmec.2023.100178","url":null,"abstract":"<div><p>The present study considers the nonlinear vibration behavior of a beam with general boundary conditions that carry an electrical current in the magnetic field. This paper discusses the magnetic couple, the transverse magnetic force, the electrical current, and the damper. By contrast, the magnetic field is selected as an arbitrary function of time. Under certain hypotheses, Hamilton's principle is used along with Maxwell's equations to derive the governing equation. An elastically restrained beam carrying an electrical current is also solved using Galerkin's method under a magnetic field. Thus, the effect of the rotational and the translational support flexibilities, the magnetic field, and other parameters are evaluated. For a more detailed investigation, some numerical examples are investigated to present the simplicity and efficiency of this formulation. Based on the numerical results, it is clear that the natural frequency of the ferromagnetic beam is sensitive to the angle and magnetic field. By increasing magnetic field intensity, the magnitude of the natural frequency of the beam increases. But with the increase of the angle, the frequency value decreases. Therefore, at larger angles, the impact of the intensity of the magnetic field will be less. Also, it is determined from the results that the beam deflection in various magnetic fields indicates a significant effect of the boundary conditions, not only on the dynamic response of a damped beam but also on the rate of damping of the response. The dynamic response under the magnetic field is decreased when the beam experiences a stiffer constant in its support. The results are shown that the effect of stiffening for the transitional support is more significant than that of the rotational support. Also, the influence of the boundary constraints becomes smaller when the magnetic field becomes smaller.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43088692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evolution of deformation and stress during necking in uniaxial tension 单轴拉伸颈缩过程中变形和应力的演变

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100201

C. Liu

{"title":"Evolution of deformation and stress during necking in uniaxial tension","authors":"C. Liu","doi":"10.1016/j.finmec.2023.100201","DOIUrl":"https://doi.org/10.1016/j.finmec.2023.100201","url":null,"abstract":"<div><p>In this investigation, we study experimentally the evolution of both the deformation and the stress during the necking process of a thin metal sheet subject to uniaxial tension. The deformation over the sample surface is obtained using the optical technique of Digital Image Correlation (DIC), which maps out full-field displacement over a two-dimensional (2D) domain. The stress field associated with the measured deformation is determined using the technique developed by Liu [18], where if the deforming material remains isotropic, the stresses can be computed based on the measured deformation by solving the equation of equilibrium together with appropriate traction boundary conditions. The deformation measurement indicates that after the initiation of the neck the deformation in areas outside the neck is frozen, confirming what Bridgman [2] has speculated, and the deformation within the neck area continues to increase till final failure. There is never a reversal in deformation and, as a result, all material particles in the necking zone only experience softening but not unloading. The results also reveal some unique and interesting patterns of the stress field over the necking zone. Their implications on the analysis and modeling of the necking process are discussed.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49748186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sensitivity analysis of vibration response of timoshenko beam to mass ratio and velocity of moving mass and boundary conditions: Semi-analytical approach Timoshenko梁振动响应的灵敏度分析——质量比、运动速度和边界条件的半解析法

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100205

Amin Ghannadiasl , Massood Mofid

{"title":"Sensitivity analysis of vibration response of timoshenko beam to mass ratio and velocity of moving mass and boundary conditions: Semi-analytical approach","authors":"Amin Ghannadiasl , Massood Mofid","doi":"10.1016/j.finmec.2023.100205","DOIUrl":"10.1016/j.finmec.2023.100205","url":null,"abstract":"<div><p>In real-world physics phenomena, the boundary conditions of structural members in the structural beam systems affect the system response. Also, moving load or mass problems are used widely in many engineering fields, such as structural, transportation, mechanical engineering, etc. Therefore, it is necessary to study the effect of boundary conditions on beam vibrations. Hence, a semi-analytical approach for the Timoshenko beam with various boundary conditions under moving mass is presented in this paper. Dynamic Green Function is introduced for modeling the beam under moving mass. An accurate formulation is illustrated for modeling a Timoshenko beam under moving mass with different boundary conditions. Finally, some examples demonstrate to assess of the effect of different boundary conditions, the mass ratio of moving mass, and the speed of moving mass. The numerical results are shown the efficiency and simplicity of the present approach. Based on the results, it is found that the mass ratio affects the dynamic response shape. For moving mass, the delay of the maximum dynamic deflection with respect to the mass position, increases with the speed at the higher speeds. But for smaller values of the speed, the same results of the maximum dynamic deflection for the moving load model along with the moving mass model are obtained. On the other hand, the maximum dynamic deflection points of the curves move slightly towards the right end of the beam with an increasing mass ratio. Also, the location of the constraint in the asymmetric beams is more significant in dynamic response. It is found that the dynamic behavior of the beam under moving mass changes dramatically based on the type of boundary conditions. Furthermore, the displacement obtained for each boundary condition decreases with increasing mass speed.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41623411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Closed-form asymptotic micromechanics model of fiber reinforced polymer and metal matrix composites 纤维增强聚合物和金属基复合材料的闭合渐进微观力学模型

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100188

M.V. Peereswara Rao , Dineshkumar Harursampath , M.V.V.S. Murthy

{"title":"Closed-form asymptotic micromechanics model of fiber reinforced polymer and metal matrix composites","authors":"M.V. Peereswara Rao , Dineshkumar Harursampath , M.V.V.S. Murthy","doi":"10.1016/j.finmec.2023.100188","DOIUrl":"10.1016/j.finmec.2023.100188","url":null,"abstract":"<div><p>This work presents an analytical asymptotically-correct micromechanics model that helps to predict the effective material properties of a unidirectional composite material. The conventional and numerical approaches estimate the homogenized material properties of composites for their defined component volume fractions, their constituent properties and configurational geometry. Presently these approaches are based on kinematic assumptions such as having displacement or stress components vary through the cross section for beam like structures or through the thickness for plate like structures according to certain predefined functions that doesn’t always logically follow the 3D analysis. In the present formulation, the micromechanics model is developed by accommodating all possible deformations without assuming the displacement function or stress components. These are derived by minimizing the potential energy in terms of generalized strain measures. In the present formulation, Berdichevsky’s Variational Asymptotic Method (VAM) is employed as a mathematical tool to accomplish the homogenization procedure. The Hashin-Rosen model popularly referred to as the Concentric Cylinder Model (CCM) serves as the framework to estimate all the relevant homogenized elastic moduli and coupling coefficients. The derived quantities of interest are obtained as closed form expressions which are functions of the properties of the reinforcement material, the matrix material, their volumes fraction and the geometry of their relative arrangement. These expressions are arrived following the 3D elasticity governing rules by satisfying the interfacial displacement continuity and transverse stress equilibria conditions at the reinforcement and matrix materials interface. The developed expressions for the elastic moduli, shear moduli and Poisson’s ratios of few typical polymer and metal matrix composite materials are validated with some of the relevant results available in the literature.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45954073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EDL Aspects in swirling ionic tribological fluid flow in a squeezed/split channel underlie a high-power magnetic field 高功率磁场下挤压/分裂通道中旋转离子摩擦学流体流动的EDL方面

Forces in mechanics Pub Date : 2023-05-01 DOI: 10.1016/j.finmec.2023.100196

Subhendu Das, Sanatan Das

{"title":"EDL Aspects in swirling ionic tribological fluid flow in a squeezed/split channel underlie a high-power magnetic field","authors":"Subhendu Das, Sanatan Das","doi":"10.1016/j.finmec.2023.100196","DOIUrl":"10.1016/j.finmec.2023.100196","url":null,"abstract":"<div><p>Studying electrokinetic swirling flows of ionic tribological fluid in a squeezing/splitting scenario has drawn a lot of interest due to its extensive dispensations in mechanical and manufacturing engineering. The present modelling and simulation-based study deals with an in-depth physical exploration of electric double layer (EDL) aspects in a swirling flow via a squeezing/splitting perforated channel filled with ionic tribological fluid when subjected to a high-power magnetic field with Hall current. The rudimentary momentum equations are presented by assigning partial differential equations (PDEs), which are then transmuted into non-linear ordinary differential equations (ODEs) using a compatible similarity substitution. The reduced system of coupled non-linear ODEs with proposed boundary data is dealt with numerically by dint of Runge-Kutta-Fehlberg (RKF45) formula-based shooting scheme, namely Mathematica in-built routine function bvp4c. By plotting distinctive graphs and tables, the physical impacts of emerging model parameters upon the moment profiles and engineering entities of interest are explored and interpreted. Simulated outcomes unravel with an intensification in electroosmosis and rotation parameters, the fluid pressure is discerned to rise near the channel plates while a contrary affinity prevails in the central passage. The shear impedance can be minified by adjusting the squeezing velocity. The imprinted flowlines plots unfold that the reverse flow is noticeable with the negative suction parameter. Our squeezing flow model might apply to tunnelling, semiconductors, sensing and control systems, spacecraft designing, etc.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43437518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2