Forces in mechanics最新文献

{"title":"Evaluation of static and dynamic responses considering thickness stretching effect for layered composite and sandwich arches using exponential shear and normal deformation theory","authors":"Valmik M. Mahajan ,&nbsp;Amit Sharma","doi":"10.1016/j.finmec.2023.100204","DOIUrl":"10.1016/j.finmec.2023.100204","url":null,"abstract":"<div><p>Present theory investigates the dimensionless vibration frequencies, deformations, and stresses for multilayered and sandwich arches using exponential shear and normal deformation theory (ESNDT). Present studies consider the effect of <span><math><mrow><mo>[</mo><mrow><mn>1</mn><mo>+</mo><mo>(</mo><mrow><mi>z</mi><mo>/</mo><mi>R</mi></mrow><mo>)</mo></mrow><mo>]</mo></mrow></math></span>radius of curvature while selecting the displacement field of arches under the action of uniform load. It includes the effects of transverse shear <span><math><mrow><mo>(</mo><mrow><msub><mi>γ</mi><mrow><mi>x</mi><mi>z</mi></mrow></msub><mo>≠</mo><mn>0</mn></mrow><mo>)</mo></mrow></math></span> and transverse normal deformation<span><math><mrow><mo>(</mo><mrow><msub><mrow><mi>ε</mi></mrow><mi>z</mi></msub><mspace></mspace><mo>≠</mo><mspace></mspace><mn>0</mn></mrow><mo>)</mo></mrow></math></span> <em>i.e.,</em> effect of thickness stretching. The governing relations are obtained using the Navier's method, and Hamilton's virtual work principle. The proposed layered arches are completely free from shear correction, and its top and bottom surfaces is satisfies zero traction free end conditions. Present study obtained very accurate natural frequencies for layered sandwich arches than other theories because, available literature not considered the thickness stretching effect <em>i.e.,</em><span><math><mrow><mo>(</mo><mrow><msub><mrow><mi>ε</mi></mrow><mi>z</mi></msub><mspace></mspace><mo>=</mo><mn>0</mn></mrow><mo>)</mo></mrow></math></span>. Hence, the present scientific investigation accounts the effect of thickness stretching <em>i.e.,</em><span><math><mrow><mo>(</mo><mrow><msub><mrow><mi>ε</mi></mrow><mi>z</mi></msub><mspace></mspace><mo>≠</mo><mspace></mspace><mn>0</mn></mrow><mo>)</mo></mrow></math></span>. However, the non-availability of exact elasticity results of bending and dynamic responses for layered sandwich arches. Present theory is obtained vibration frequencies, displacements, and stresses of layered composite and sandwich arches; the results are compared and validates through prior published literature.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100204"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41668572","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}

{"title":"Non-local effect of eccentrically simply supported beam on free vibration","authors":"Bojin Li ,&nbsp;Diyun Wen ,&nbsp;Xin-Chun Shang ,&nbsp;Rui Zhang","doi":"10.1016/j.finmec.2023.100218","DOIUrl":"10.1016/j.finmec.2023.100218","url":null,"abstract":"<div><p>Based on the Euler-Bernoulli beam theory, the coupling effect between bending vibration mode shape and longitudinal vibration mode shape of the beam is analyzed when the beam is supported by eccentric simply supported. Under the assumption of small deformation, the vibration control equations and the coupling boundary conditions are obtained through Hamilton's principle and the principle of virtual work variation. The numerical results under three different boundary conditions are given. It shows that the natural frequencies of the beam vary with the eccentricity distances are in complete agreement with the results obtained from finite element analysis and literature. The results strongly proved the validity and correctness of the coupling method in this paper. It also indicates that eccentric simply supported constraints have non-local effects.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100218"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42963577","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}

{"title":"Finite difference analysis on radiative flow on a perpendicular plate using the influence of thermal conductivity","authors":"D. Iranian ,&nbsp;K. Sudarmozhi ,&nbsp;S. Karthik ,&nbsp;J. Manigandan ,&nbsp;Ali J. Chamkha","doi":"10.1016/j.finmec.2023.100217","DOIUrl":"10.1016/j.finmec.2023.100217","url":null,"abstract":"<div><p>This study aims to investigate the influence of radiation, thermal conductivity and variable viscosity on natural convective flow on a semi-infinite perpendicular plate. Variable viscosity, thermal conductivity and thermal radiation are considered for the given study. The dimensional governing equations are framed with the use of the mentioned parameters and then these equations were converted into dimensionless equations by applying non dimensional quantities. The main aim of this study is to find the Nusselt number and skin friction for both air and water for considered parameters. Using the finite difference method through Fortran software, numerical solutions to the governing heat equations and dimensionless momentum equations were computed. The results for the parameters thermal conductivity, variable viscosity, radiation, and Prandtl number for both air and water are displayed via various graphs. The skin friction coefficients, Nusselt parameter, and local Nusselt numbers were discussed for both the air and water. The key conclusions of this study are that the succeeding velocity declines as the radiation's increases. By increasing the radiation value and the fluctuation time, the temperature distribution increases. Notably, the temperature profile increases significantly when the variable viscosity parameter decreases.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100217"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43928855","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}

{"title":"Comprehensive analysis and economic study of railway brake failure from metal-based and composites-based materials","authors":"Muhammad Akhsin Muflikhun ,&nbsp;Mayradaffa Adyudya ,&nbsp;Nur Fatah Rahman ,&nbsp;Jayan Sentanuhady ,&nbsp;Swathi Naidu Vakamulla Raghu","doi":"10.1016/j.finmec.2023.100223","DOIUrl":"10.1016/j.finmec.2023.100223","url":null,"abstract":"<div><p>The brake system is one of the most critical components in transportation, especially for massive machines such as trains. Brake components decelerate the train by using friction force between the train wheels and the brake block. The efficacy of a brake system strongly depends on the quality of the material components, especially the brake blocks. This study investigated the failure brake block on three different model of brake blocks used in Indonesia (grey cast iron, composite, and magnetic composite). Several characteristics and evaluations are used, i.e., non-destructive surface analysis, microhardness, Energy Dispersive X-Ray (EDX) analysis, and computational Finite Element Method (FEM). The microscopic analysis showed severe conditions at the non-magnetic brake, followed by the magnetic brake. The roughness test indicates that the Ra value for the magnetic brake is higher than the non-magnetic composite brake, with 4.59 and 4.08, respectively. The micro hardness test revealed that in metal-based materials indentation, the results showed magnetic composite has the highest value followed by cast iron and non-magnetic composite with 306, 283, and 218, respectively. In EDX examination, magnetic brakes have filler materials such as Calcium Carbonate and Wollastonite that create better performance. The study showed that the magnetic composite brake blocks demonstrate adequate resistance to failure due to the composite's filler material, which acts as a reinforcing agent.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100223"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41848951","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}

{"title":"Influences of Stefan blowing on unsteady flow of Casson nanofluid past a stretching surface","authors":"Saheb Konai,&nbsp;Hiranmoy Maiti,&nbsp;Swati Mukhopadhyay","doi":"10.1016/j.finmec.2023.100227","DOIUrl":"10.1016/j.finmec.2023.100227","url":null,"abstract":"<div><p>This paper deals with the flow of non-Newtonian nanoliquid past an unsteady stretched exterior in attendance of Stefan blowing/suction. Model for Casson liquid has been taken into account to represent the non-Newtonian liquid. Two phase fluid replica for nanofluid has been considered. Similarity alterations are applied to transform the leading pdes (partial differential equations) to ordinary ones. Runge–Kutta method of order four has been used to solve the altered equations numerically with the help of shooting technique. Wall shear stress, heat and mass transfer coefficients diminish with the rise in unsteadiness. Fluid's velocity and temperature are found to rise with the enhancement in Stefan blowing/suction parameter. Temperature of the fluid rises but fluid's velocity diminishes for the rising values of Casson parameter. Basically, the pertinent parameters affect the stream, warmth and accumulation transport significantly which can be viewed by the figures and tables presented here and also by their physical analysis.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100227"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44589370","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}

{"title":"Extending a generic and fast coarse-grained molecular dynamics model to examine the mechanical behavior of grafted polymer nanocomposites","authors":"Maximilian Ries,&nbsp;Sebastian Reber,&nbsp;Paul Steinmann,&nbsp;Sebastian Pfaller","doi":"10.1016/j.finmec.2023.100207","DOIUrl":"10.1016/j.finmec.2023.100207","url":null,"abstract":"<div><p>Polymer nanocomposites are an important class of materials for engineering applications due to their high versatility and good mechanical properties combined with low density. By directly attaching the polymer chains to the nanofillers, the so-called grafting, a better load transfer between matrix and filler is achieved, and, in addition, a better dispersion of the fillers is obtained. Both result in enhanced mechanical properties. Since experimental investigations on the nanoscale are extremely challenging, complementary numerical studies are needed to unravel the mechanical behavior of polymer nanocomposites. To this end, molecular dynamics is ideally suited since it captures the microstructure, but is also numerically expensive. Therefore, this contribution presents a fast coarse-grained molecular dynamics model for the investigation of the mechanical behavior of grafted polymer nanocomposites. For this purpose, we extend an existing model by grafting bonds, which allows us to compare the effect of untreated and grafted fillers directly. In particular, we investigate the influence of filler content, grafting degree, and filler size on the stiffness and strength of the polymer (grafted) nanocomposites. We conclude that the grafting bonds have little effect on the stiffness, while the strength is significantly improved compared to the untreated fillers, which is in agreement with the literature. The presented molecular dynamics model for polymer grafted nanocomposites provides the basis for further investigations, particularly of the crucial matrix-filler interphase. In addition, this contribution translates molecular dynamics insights into mechanical properties, which bridges the gap to the engineering scale and thus represents a step towards exploiting the full potential of polymer (grafted) nanocomposites.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100207"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48293648","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}

{"title":"Onsager’s reciprocal relationship applied to multiphysics poromechanics","authors":"Klaus Regenauer-Lieb ,&nbsp;Manman Hu","doi":"10.1016/j.finmec.2023.100213","DOIUrl":"10.1016/j.finmec.2023.100213","url":null,"abstract":"<div><p>Onsager’s theory of linear irreversible thermodynamics has been successfully applied to explain findings from experiments. However, its application to multiphysics processes in deformable porous media is a non-trivial undertaking. This contribution presents an extension of Onsager’s theorem to include the flux of the matter of weakly coupled two-phase porous systems. It also relates Onsager to Ziegler’s nonlinear approach including the classical acoustic tensor criterion for localisation phenomena in such nonlinear media. The results are illustrated by Terzaghi consolidation problem using the well established modified Cam-Clay plasticity model. We show that a generalised dissipative stress can act as an appropriate thermodynamic force quantity rendering the non-associated yield envelope into Onsager’s associated form ensuring the thermodynamic condition of no-work free plastic deformation. We present in this contribution an attempt of using the theory of thermodynamics of internal state variables to develop a generic poromechanics approach that relaxes isothermal constraints for weakly coupled problems. This approach lends itself to a promising future extension of a dynamic Onsager diffusional operator for conditions where the multiphysics processes are strongly coupled in the porous system and emergent phenomena may occur.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100213"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48670512","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}

{"title":"Free Vibration Analysis of Tapered Rayleigh Beams resting on Variable Two-Parameter Elastic Foundation","authors":"Olanrewaju T. Olotu ,&nbsp;Jacob A. Gbadeyan ,&nbsp;Olasunmbo O. Agboola","doi":"10.1016/j.finmec.2023.100215","DOIUrl":"10.1016/j.finmec.2023.100215","url":null,"abstract":"<div><p>This study aims at analyzing the effect of variable foundation parameters on the natural frequencies of a prestressed tapered Rayleigh beam having general elastically restrained ends. In this work, the elastic coefficients of the foundations are assumed varying along the beam major axis. In particular, the constant, linear and parabolic variations of the Pasternak foundation are considered. A semi-analytical approach known as differential transform method (DTM) is applied to the non-dimensional form of the governing equations of motion of the prestressed tapered Rayleigh beam and a set of recurrence algebraic equations are determined. Performing some direct algebraic operations on these derived equations and using some computer codes developed and implemented in MAPLE 18, the dimensionless natural frequencies and the associated mode shapes of the beam are obtained, the effects of these Pasternak foundation variations for various values of the slenderness ratio on the natural frequencies are investigated. It is found among others that : (i) an increase in foundation stiffness led generally to an increase in the natural frequencies; (ii) the constant elastic variations of Pasternak foundation produced highest values of natural frequencies; and (iii) the natural frequencies of tapered Rayleigh beam resting on Pasternak foundation are higher than those from the same beam on Winkler foundation. Finally, the efficiency and accuracy of differential transform method are illustrated by solving two numerical examples of vibration problems and validating the results obtained with those in the open literature, and are found to compare favorably well.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100215"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48759250","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}

{"title":"Strain-induced damage analysis of hyperelastic material through scanning electron microscopy: A statistical approach using digital image processing","authors":"Md Moonim Lateefi,&nbsp;Firozut Tauheed,&nbsp;Somnath Sarangi","doi":"10.1016/j.finmec.2023.100225","DOIUrl":"10.1016/j.finmec.2023.100225","url":null,"abstract":"<div><p>In order to acquire topographic/morphological images with superior resolution and depth of focus than an ordinary optical microscope, scanning electron microscopy (SEM) is used to take photographs of a surface of materials or specimens at a desired point. In the context of polymer and rubber materials science, SEM investigations frequently try to visualize phase morphology, surface and cross-sectional topography, and surface molecular order, and clarify damage mechanisms. In the case of rubber vulcanizates, test specimens are frequently put through a variety of mechanical property assessment procedures, including tensile, flexing, fatigue, abrasion, and tear tests, in order to finalize compounding parameters for required levels of quality. The damaged surface of the test specimens exhibits distinctive topographical characteristics, which are captured as an SEM picture and associated with relevant strength properties. However, the majority of the time, the relationship between strength attributes and the type of surface topography is qualitative. Surface roughness measurement metrics such as root mean square (r.m.s) roughness, average roughness, and peak-to-valley distance are frequently determined for quantitative research using standard software accessible in an SEM. The primary goal of this research is to use a statistical/spectral-based technique for quantitatively measuring surface topography using SEM. The Mullins stress-softening phenomenon of an isotropic, incompressible, hyperelastic rubberlike material is predicted using a phenomenological model. A simple exponential damage function characterizes the model, which represents deformation-induced microstructural degradation of rubberlike material.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"12 ","pages":"Article 100225"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46354150","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}

{"title":"Effect of forming strain on low cycle, high cycle and notch fatigue performance of automotive grade dual phase steels: A review","authors":"Surajit Kumar Paul","doi":"10.1016/j.finmec.2023.100184","DOIUrl":"10.1016/j.finmec.2023.100184","url":null,"abstract":"<div><p>In many engineering structural applications, including car body structures, sheet metal formed components are used. A systematic investigation of the impact of forming strain on fatigue life is necessary for an accurate prediction of a formed component's fatigue life. The present work aims to determine the impact of diverse types of tensile pre-straining on high cycle fatigue (HCF), low cycle fatigue (LCF) and notch fatigue performance of automotive grade dual phase steels. In all examined pre-straining conditions, HCF life improves, LCF life deteriorates, and little change in notch fatigue life are observed. The most significant improvement in HCF life and deterioration in LCF life are observed for equi-biaxial and orthogonal tensile pre-straining conditions due to the rotation of maximum shear stress plane and the rotation of the deformation concentrated region around the hard martensite. As the strength improves during pre-straining, there is a corresponding increase in stress concentration around a notch, and as a result, no significant change in notch fatigue life is observed.</p></div>","PeriodicalId":93433,"journal":{"name":"Forces in mechanics","volume":"11 ","pages":"Article 100184"},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48283511","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}