Mechanics & Industry最新文献_第8页

Identification of the pore size distribution of a porous medium by yield stress fluids using Herschel-Bulkley model 用Herschel-Bulkley模型识别屈服应力流体中多孔介质的孔径分布

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-08-10 DOI: 10.1051/meca/2020032

Aimad Oukhlef, A. Ambari, S. Champmartin

{"title":"Identification of the pore size distribution of a porous medium by yield stress fluids using Herschel-Bulkley model","authors":"Aimad Oukhlef, A. Ambari, S. Champmartin","doi":"10.1051/meca/2020032","DOIUrl":"https://doi.org/10.1051/meca/2020032","url":null,"abstract":"In this paper, we present a new method to determine the pore-size distribution (PSD) in a porous medium. This innovative technique uses the rheological properties of non-Newtonian yield stress fluids flowing through the porous sample. In a first approach, the capillary bundle model will be used. The PSD is obtained from the measurement of the total flow rate of fluid as a function of the imposed pressure gradient magnitude. The mathematical processing of the experimental data, which depends on the type of yield stress fluid, provides an overview of the pore size distribution of the porous material. The technique proposed here was successfully tested analytically and numerically for usual pore size distributions such as the Gaussian mono and multimodal distributions. The study was conducted for yield stress fluids obeying the classical Bingham model and extended to the more realistic Herschel-Bulkley model. Unlike other complex methods, expensive and sometimes toxic, this technique presents a lower cost, requires simple measurements and is easy to interpret. This new method could become in the future an alternative, non-toxic and cheap method for the characterization of porous materials.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86298801","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

The non-isothermal hot deep drawing of AA5083 aluminum alloy AA5083铝合金的非等温热拉深

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-08-01 DOI: 10.1051/meca/2019090

Abozar Barimani Varandi

引用次数: 7

Analysis of torsional vibration effect on the diesel engine block vibration 扭振对柴油机机体振动的影响分析

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-07-01 DOI: 10.1051/meca/2020065

Shiwei Ni, Yibin Guo, Binglin Lv, Donghua Wang, Wanyou Li, Zhijun Shuai

引用次数: 1

Effects of double parabolic profiles with groove textures on the hydrodynamic lubrication performance of journal bearing under steady operating conditions 带沟槽织构的双抛物线型对滑动轴承稳态润滑性能的影响

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-07-01 DOI: 10.1051/meca/2020018

Chongpei Liu, Wanyou Li, Xi-qun Lu, Bin Zhao

{"title":"Effects of double parabolic profiles with groove textures on the hydrodynamic lubrication performance of journal bearing under steady operating conditions","authors":"Chongpei Liu, Wanyou Li, Xi-qun Lu, Bin Zhao","doi":"10.1051/meca/2020018","DOIUrl":"https://doi.org/10.1051/meca/2020018","url":null,"abstract":"The textures on the bushing surface have important effects on the performance of journal bearing. In this study, the effects of double parabolic profiles with groove textures on the hydrodynamic lubrication performance of journal bearing under steady operating conditions are investigated theoretically. The journal misalignment, asperity contact and thermal effects are considered, while the profile modifications due to running-in are neglected. The Winkler/Column model is used to calculate the elastic deformation of bushing surface and the adiabatic flow hypothesis is adopted to obtain the effective temperature of lubricating oil. The numerical solution is established by using finite difference and overrelaxation iterative methods, and the rupture zone of oil film is determined by Reynolds boundary conditions. The numerical results reveal that the double parabolic profiles with groove textures with proper location and geometric sizes can increase load carrying capacity and reduce friction loss under steady operating conditions, which effectively overcome the drawbacks of double parabolic profiles. This novel bushing profile may help to reduce the bushing edge wear and enhance the lubrication performance of journal bearing.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74894059","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: 3

Seismic vulnerability of structures: application to the Civil Protection building in Andorra 结构的地震易损性:在安道尔民防建筑中的应用

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-19 DOI: 10.1051/meca/2020045

Matthias Barus, O. Dalverny, H. Welemane, J. Faye, Carmen Martin

{"title":"Seismic vulnerability of structures: application to the Civil Protection building in Andorra","authors":"Matthias Barus, O. Dalverny, H. Welemane, J. Faye, Carmen Martin","doi":"10.1051/meca/2020045","DOIUrl":"https://doi.org/10.1051/meca/2020045","url":null,"abstract":"This works deals with the seismic vulnerability of buildings in the Pyrenees mountains region where almost a thousand earthquakes are recorded each year in the border area. The challenge is twofold: first to detect the damage due to seismic events and then to localize it inside studied buildings. Operational Modal Analysis (OMA) coupled with numerical modelling by Finite Element (FE) constitutes an interesting approach to address these issues. Here we intend to apply such methodology on a strategic building located in Andorre-la-Vieille whose structure is complex, irregular and heterogeneous. The structural behaviour of the building is studied through frequency computation method in order to identify its undamaged behaviour. A seismic event is next simulated by a non-linear dynamic computation method which creates damage within the structure. Numerical results (natural frequencies, modal shapes and damage location) allow highlighting damaged zones induced by the earthquake and quantify degradation level in these areas. Accordingly, some guidelines may be given in view of the future instrumentation of the building (accelerometers and RAR).","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86269558","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

FEM based mathematical modelling of thrust force during drilling of Al7075-T6 基于有限元的Al7075-T6钻削推力数学模型

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-01 DOI: 10.1051/meca/2020046

A. Tzotzis, C. García-Hernández, José-Luis Huertas-Talón, P. Kyratsis

引用次数: 7

Variational approach for mechatronic tolerancing: application to a DC motor 机电公差的变分方法:在直流电机上的应用

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-01 DOI: 10.1051/meca/2019056

Hana Siala, F. Mhenni, M. Barkallah, J. Choley, J. Louati, M. Haddar

{"title":"Variational approach for mechatronic tolerancing: application to a DC motor","authors":"Hana Siala, F. Mhenni, M. Barkallah, J. Choley, J. Louati, M. Haddar","doi":"10.1051/meca/2019056","DOIUrl":"https://doi.org/10.1051/meca/2019056","url":null,"abstract":"Having an increasingly complex set of inter-relations between several components from different domains, mechatronic systems become more and more complex. The behavior of such systems depends on the values of their parameters and variables. A deviation of these values from their expected values affects the overall functioning of the system, degrades the system quality, and may be a significant threat to safety. To reach an expected quality level, the deviations between actual and target values of parameters should be within specified tolerances. For this, two extreme limits (i.e. upper and lower bounds) of these values must be wisely determined. It is also important to know the impact of parameters deviations on system behavior. Furthermore, the margin of variables should be controlled to evaluate system performance with respect to the specifications, requirements and user needs. This paper describes a methodology based on a variational approach combined with Worst-Case Analysis and Monte Carlo Simulation to determine the impact of the parameters variation on the system behavior. It helps designers to analyze tolerances of mechatronic systems. Our proposed methodology is illustrated with a DC motor case study. The results show that the developed method provides a new way for mechatronic tolerancing.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88881926","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

Multi-objective optimization of a sports car suspension system using simplified quarter-car models 基于简化四分之一车模型的跑车悬架系统多目标优化

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-01 DOI: 10.1051/meca/2020039

S. Ebrahimi-Nejad, Majid Kheybari, Seyed Vahid Nourbakhsh Borujerd

{"title":"Multi-objective optimization of a sports car suspension system using simplified quarter-car models","authors":"S. Ebrahimi-Nejad, Majid Kheybari, Seyed Vahid Nourbakhsh Borujerd","doi":"10.1051/meca/2020039","DOIUrl":"https://doi.org/10.1051/meca/2020039","url":null,"abstract":"In this paper, first, the vibrational governing equations for the suspension system of a selected sports car were derived using Lagrange's Equations. Then, numerical solutions of the equations were obtained to find the characteristic roots of the oscillating system, and the natural frequencies, mode shapes, and mass and stiffness matrices were obtained and verified. Next, the responses to unit step and unit impulse inputs were obtained. The paper compares the effects of various values of the damping coefficient and spring stiffness in order to identify which combination causes better suspension system performance. In this regard, we obtained and compared the time histories and the overshoot values of vehicle unsprung and sprung mass velocities, unsprung mass displacement, and suspension travel for various values of suspension stiffness (KS ) and damping (CS ) in a quarter-car model. Results indicate that the impulse imparted to the wheel is not affected by the values of CS and KS . Increasing KS will increase the maximum values of unsprung and sprung mass velocities and displacements, and increasing the value of CS slightly reduces the maximum values. By increasing both KS and CS we will have a smaller maximum suspension travel value. Although lower values of CS provide better ride quality, very low values are not effective. On the other hand, high values of CS and KS result in a stiffer suspension and the suspension will provide better handling and agility; the suspension should be designed with the best combination of design variables and operation parameters to provide optimum vibration performance. Finally, multi-objective optimization has been performed with the approach of choosing the best value for CS and KS and decreasing the maximum accelerations and displacements of unsprung and sprung masses, according to the TOPSIS method. Based on optimization results, the optimum range of KS is between 130 000–170 000, and the most favorable is 150, and 500 is the optimal mode for CS .","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89559251","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: 13

Effect of multi-pass friction stir processing on thermal distribution and mechanical properties of AZ91 多道次搅拌摩擦处理对AZ91热分布和力学性能的影响

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-01 DOI: 10.1051/meca/2020042

H. A. A. Fashami, N. Arab, M. H. Gollo, Bahram Nami

{"title":"Effect of multi-pass friction stir processing on thermal distribution and mechanical properties of AZ91","authors":"H. A. A. Fashami, N. Arab, M. H. Gollo, Bahram Nami","doi":"10.1051/meca/2020042","DOIUrl":"https://doi.org/10.1051/meca/2020042","url":null,"abstract":"In this paper, the effect of multi-pass friction stir processing on mechanical properties of AZ91 alloy has been studied. For this purpose, the microhardness, tensile, and creep tests were conducted at several temperatures. Optical microscopy and scanning electron micrograph were used to study the microstructure of the processed samples. The experimental results indicated that at room temperature, the microhardness, tensile, and creep strength of the processed samples as compared to the unprocessed ones increased by 23%, 29%, and 38%, respectively. Also, after friction stir processing, the tensile and creep strength of the samples at 210 °C increased by 31% and 47%. In addition, a three-dimensional model was developed to simulate two-pass friction stir processing using ABAQUS/Explicit software. This model involved the Johnson-Cook models for defining material behavior during the process and identifying the fracture criterion. To control the mesh distortion during consecutive passes, the Arbitrary Lagrangian-Eulerian technique was used. Using the developed model, the peak temperature, thermal distribution, and residual stress field during multi-pass friction stir processing on AZ91 have been studied. The empirical results indicated the beneficial influence of the multi-pass friction stir processing on the microstructure and high-temperature mechanical properties of AZ91 alloy.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90536807","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: 5

Mixed H2/H∞ guaranteed cost control for high speed elevator active guide shoe with parametric uncertainties 具有参数不确定性的高速电梯主动导靴混合H2/H∞保成本控制

IF 1.2 4区工程技术

Mechanics & Industry Pub Date : 2020-05-01 DOI: 10.1051/meca/2020044

Chen Chen, Ruijun Zhang, Qing Zhang, Liu Lixin

{"title":"Mixed H2/H∞ guaranteed cost control for high speed elevator active guide shoe with parametric uncertainties","authors":"Chen Chen, Ruijun Zhang, Qing Zhang, Liu Lixin","doi":"10.1051/meca/2020044","DOIUrl":"https://doi.org/10.1051/meca/2020044","url":null,"abstract":"Aiming at the phenomenon that the elevator car system generates horizontal vibration due to the unevenness of the guide rail and the guide shoe modeling uncertainty caused by friction, wear and spring aging between the rolling guide shoe and the guide rail, a mixed H2/H∞ optimal guaranteed cost state feedback control strategy is proposed. Firstly, as the high-speed elevator car system always exist the phenomenon of stiffness and damping uncertainty in the guide shoe, the LFT method is adopted to construct the state space equation of the car system with parameter uncertainty. Secondly, considering the performance indexes of horizontal acceleration at the center of the car floor and the guide shoe vibration displacement system, an optimal guaranteed performance state feedback controller is designed based on the linear convex optimization method, which to minimize H2 performance index and achieve the specified H∞ performance level. Thirdly, the free matrix is introduced to reduce the conservatism of the controller. Finally, by comparing the simulation results with other control methods under the same conditions, it is verified that the control strategy can make the car system have better vibration suppression ability, and can significantly improve the ride comfort of the elevator.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75196124","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: 9