Archives of Mechanics最新文献

Comparative FE-studies of interface behavior of granular Cosserat materials under constant pressure and constant volume conditions 恒压和恒容条件下颗粒状coserat材料界面行为的fe对比研究

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-10-25 DOI: 10.24423/AOM.3726

B. Ebrahimian, M. Alsaleh, A. Kahbasi

{"title":"Comparative FE-studies of interface behavior of granular Cosserat materials under constant pressure and constant volume conditions","authors":"B. Ebrahimian, M. Alsaleh, A. Kahbasi","doi":"10.24423/AOM.3726","DOIUrl":"https://doi.org/10.24423/AOM.3726","url":null,"abstract":"This article shows the outcomes of a systematic series of finite element (FE) calculations relevant to the shear behavior of a particulate-continuum interface system under different normal boundary conditions. In this respect, shearing of a thin and long granular Cosserat layer in the vicinity of a rigid moving wall with varied surface roughness values is analyzed under constant normal pressure and constant volume conditions. The material behavior is defined with a special elasto-plastic Cosserat model, taking into account micro-rotation, micro-curvature, couple stress, and mean particle size. The interaction between the layer of boundary particles and the surface roughness of the adjoining bottom wall is modeled by the rotation resistance of particles along the wall surface. Herein, the coupled effects of normal confining constraints imposed on the layer and the surface roughness of the bottom wall, are considered on the response of granular material under shearing. The influences of pressure level and initial void ratio are explored as well. Numerical results demonstrate that the dilatancy constraint prescribed to the interface plane in the normal direction, and the wall roughness have visible influences on the interface shear resistance as well as the deformation field formed within the layer. After large shearing, the width of the localized zone along the wall does not necessarily depend on the normal confining constraint and the applied pressure level. However, the localized zone characteristics and the interface shear response are mainly affected by the initial void ratio of the material. In addition to FE analyses, DEM-based simulations are also performed to investigate the micro-mechanical response of granular medium adjacent to a wall under shearing. FE predictions are qualitatively compared with DEM results, and reasonable agreement is observed.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48943226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of a geometrically nonlinear elastoplastic gradient-enhanced damage model with incremental potential to composite microstructures 几何非线性增量势弹塑性梯度增强损伤模型在复合材料微结构中的应用

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-10-20 DOI: 10.24423/AOM.3813

H. Boussetta, J. Dittmann, S. Wulfinghoff

{"title":"Application of a geometrically nonlinear elastoplastic gradient-enhanced damage model with incremental potential to composite microstructures","authors":"H. Boussetta, J. Dittmann, S. Wulfinghoff","doi":"10.24423/AOM.3813","DOIUrl":"https://doi.org/10.24423/AOM.3813","url":null,"abstract":"The prediction of inelastic processes like plastic deformations and cracks within the microstructure of modern man-made materials by realistic, yet simple and efficient continuum models remains a major task in material modelling. For this purpose, gradient-extended standard dissipative solids represent one of the most promising model classes, which is also formulated and applied in this work to investigate microscopic failure mechanisms in three exemplary three-dimensional composite microstructures. The model combines geometrically nonlinear isotropic elastoplasticity with an isotropic damage model with gradient-extension. For the numerical treatment, a variational constitutive update algorithm based on the exponential map is applied. The model is used to provide insight into the microscopic failure of a brittle woven composite material, a particle-reinforced plastic and a carbon fiber reinforced composite. The influence of different microstructural and material parameters on the overall failure behavior is characterized. Adaptive meshing is used to enable a refined numerical resolution of the cracked regions.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48531744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transient dynamic analysis of functionally graded micro-beams considering small-scale effects 考虑小尺度效应的功能梯度微梁瞬态动力学分析

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-08-16 DOI: 10.24423/AOM.3786

I. Eshraghi, S. Dag

引用次数: 2

Rotorcraft thickness noise control 旋翼机厚度噪声控制

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-08-16 DOI: 10.24423/AOM.3756

O. Szulc

{"title":"Rotorcraft thickness noise control","authors":"O. Szulc","doi":"10.24423/AOM.3756","DOIUrl":"https://doi.org/10.24423/AOM.3756","url":null,"abstract":"The paper describes an innovative idea of Thickness Noise Control (TNC) based on adoption of a flow control strategy (i.e. surface ventilation) for acoustic attenuation of helicopter rotor periodic noise. The TNC method is relying on incorporation of multiple cavities (closed by perforated panels and linked to low- and high-pressure reservoirs) located in a symmetrical manner at front and rear portions of the blade tip. The efficiency of the new approach is verified using a two-bladed model rotor of Purcell (untwisted variant of the blade of Bell UH-1H Iroquois helicopter) in low-thrust hover conditions. The results of numerical simulations, obtained with CFD solver (Spalart–Allmaras turbulence and Bohning–Doerffer transpiration models), indicate that in the near-field of the blade tip, both the amplitude and spectral contents of pressure impulses of emitted thickness noise are significantly improved. The TNC method, in the proposed unsteady mode of operation, turns out to be a suitable means of thickness noise reduction in forward flight. Moreover, it is demonstrated that by proper azimuthal activation the efficiency is almost unaltered, while the rotor torque penalty and required transpiration mass-flux are decreased by a factor of 3–5 compared to a steady arrangement.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42749347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Problems of steady vibrations in the coupled linear theory of double-porosity viscoelastic materials 双重孔隙粘弹性材料线性耦合理论中的稳态振动问题

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-08-09 DOI: 10.24423/AOM.3856

M. Svanadze

引用次数: 4

Quasi-static and dynamic characterization of ultrafine-grained 2017A-T4 aluminium alloy processed by accumulative roll bonding 累积辊焊超细晶2017A-T4铝合金的准静态和动态特性

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-08-09 DOI: 10.24423/AOM.3795

A. Halimi, A. Boudiaf, L. Hemmouche, A. Medjahed, D. Tria, A. Henniche, M. Djeghlal, T. Baudin

{"title":"Quasi-static and dynamic characterization of ultrafine-grained 2017A-T4 aluminium alloy processed by accumulative roll bonding","authors":"A. Halimi, A. Boudiaf, L. Hemmouche, A. Medjahed, D. Tria, A. Henniche, M. Djeghlal, T. Baudin","doi":"10.24423/AOM.3795","DOIUrl":"https://doi.org/10.24423/AOM.3795","url":null,"abstract":"In this study, novel composite strips based on 2017A-T4 aluminium alloy (Al-Cu-Mg) produced by accumulative roll bonding (ARB) were developed. The microstructure and mechanical properties of the ultrafine-grained sheets under quasistatic and dynamic loadings were investigated. The initial microstructure characterization with an Optical Microscope and a Scanning Electron Microscope indicated that the ARBed sheets formed a compact material with the homogeneous and identical thickness for the individual bonded layers. Besides, the presence of precipitates was identified in all the processed strips with diverse sizes, quantities and distribution. Moreover, from Electron Back Scatter Diffraction, the microstructure was noticeably refined with increasing theARBcycles to reach 1.7 µm the grain size at the fifth cycle. The microhardness measurement and the tensile test were carried out for both natural ageing and ARBed specimens. Accordingly, the tensile stress acts on the individual layers rather than the entire sample that conduct to a reduction in the overall properties for the ARBed strips. Furthermore, a stabilization in the mechanical properties for the three first ARB cycles was noted, whereas, the domination of the dynamic recrystallization was responsible for a significant drop after the fourth cycle which is considered as the transition state. The characteristics of the compression deformation were examined under dynamic and quasi-static loadings conditions by using the Split–Hopkinson Pressure Bar system and the universal testing machine, respectively. The strain hardening behaviour was investigated using the Hollomon analysis. It was found that the thermal softening played a crucial role when compared to the strain hardening for all the studied strips. Moreover, the strain rate under the dynamic loading has a minor effect on the stress flow of the ARBed sheets compared to the as-received material.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46676260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of a discretization scheme on an autoignition time in LES of a reacting droplet-laden mixing layer 离散化方案对反应液滴混合层LES中自燃时间的影响

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-07-04 DOI: 10.24423/AOM.3546

J. Stempka, Ł. Kuban, A. Tyliszczak

{"title":"Impact of a discretization scheme on an autoignition time in LES of a reacting droplet-laden mixing layer","authors":"J. Stempka, Ł. Kuban, A. Tyliszczak","doi":"10.24423/AOM.3546","DOIUrl":"https://doi.org/10.24423/AOM.3546","url":null,"abstract":"We analyse an autoignition process in a two-phase flow in a temporally evolving mixing layer formed between streams of a cold liquid fuel (heptane at 300 K) and a hot oxidizer (air at 1000 K) flowing in opposite directions. We focus on the influence of a discretization method on the prediction of the autoignition time and evolution of the flame in its early development phase. We use a high-order code based on the 6th order compact difference method for the Navier–Stokes and continuity equations combined with the 2nd order Total Variation Diminishing (TVD) and 5th order Weighted Essentially Non-Oscillatory (WENO) schemes applied for the discretization of the advection terms in the scalar transport equations. The obtained results show that the autoignition time is more dependent on the discretization method than on the flow initial conditions, i.e., the Reynolds number and the initial turbulence intensity. In terms of mean values, the autoignition occurs approximately 15% earlier when the TVD scheme is used. In this case, the ignition phase characterizes a sharp peak in the temporal evolution of the maximum temperature. The observed differences are attributed to a more dissipative character of the TVD scheme. Its usage leads to a higher mean level of the fuel in the gaseous form and a smoother distribution of species resulting in a lower level of the scalar dissipation rate, which facilitates the autoignition process.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42343630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Ponding on an inflated tube and the membrane trough 充气管和膜槽上的积水

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-06-30 DOI: 10.24423/AOM.3765

C. Wang

引用次数: 0

Wave propagation in nonlocal orthotropic micropolar elastic solids 非局部正交各向异性微极性弹性固体中的波传播

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-06-30 DOI: 10.24423/AOM.3764

D. X. Tung

引用次数: 2

Absolute instability of double annular jets: local stability analysis 双环射流的绝对不稳定性：局部稳定性分析

IF 0.8 4区工程技术

Archives of Mechanics Pub Date : 2021-06-16 DOI: 10.24423/AOM.3732

A. Bogusławski, K. Wawrzak

引用次数: 0