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Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 410-416 doi: 10.1007/s11465-012-0341-4

摘要:

Recently, the concept of hard turning has gained considerable attention in metal cutting as it can apparently replace the traditional process cycle of turning, heat treating, and finish grinding for assembly of hard wear resistant steel parts. The present investigation aims at developing a magneto rheological (MR) fluid damper for suppressing tool vibration and promoting better cutting performance during hard turning. The magneto rheological Fluid acts as a viscoelastic spring with non-linear vibration characteristics that are controlled by the composition of the magneto rheological fluid, the shape of the plunger and the electric parameters of the magnetizing field. Cutting experiments were conducted to arrive at a set of electrical, compositional and shape parameters that can suppress tool vibration and promote better cutting performance during turning of AISI 4340 steel of 46 HRC with minimal fluid application using hard metal insert with sculptured rake face. It was observed that the use of MR fluid damper reduces tool vibration and improves the cutting performance effectively. Also commercialization of this idea holds promise to the metal cutting industry.

关键词: tool vibration     magneto rheological damper     hard turning     surface finish     tool wear    

Vibration control of a structure using Magneto-Rheological grease damper

Shinya SUGIYAMA, Tomoki SAKURAI, Shin MORISHITA

《机械工程前沿(英文)》 2013年 第8卷 第3期   页码 261-267 doi: 10.1007/s11465-013-0268-4

摘要:

This paper describes an application study of Magneto-Rheological (MR) grease damper to a structure with three stories. MR fluid is known as one of successful smart materials whose rheological properties can be varied by magnetic field strength, and has been applied to various kinds of device such as dampers, clutches, engine mounts, etc. However, ferromagnetic particles dispersed in MR fluid settle out of the suspension after a certain interval due to the density difference between the particles and their career fluid. To overcome this defect, we have developed a new type of controllable working fluid using grease as the career of magnetic particles. Network of thickener in grease is expected to hold the magnetic particles and prevent them from settled down. No or little sedimentation was observed in MR grease whose characteristics could be controlled by the magnetic field strength. MR grease was introduced into a cylindrical damper and its performance was studied. As a result, it was confirmed that the damping force of MR grease damper could be controlled by the applied electric current to the coil in the cylinder of damper. Furthermore, vibration response of a three-story model structure equipped with MR grease damper was investigated experimentally, and it was shown that MR grease damper worked effectively as a semi-active damper.

关键词: vibration control     damper     smart material     Magneto-Rheological (MR) grease     MR fluid    

Creep and recovery behaviors of magnetorheological elastomers

Weihua LI, Yang ZHOU, Tongfei TIAN, Gursel ALICI,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 341-346 doi: 10.1007/s11465-010-0096-8

摘要: This paper presents experimental and modeling study of creep and recovery behaviors of magneto-rheological elastomers (MREs) under constant stresses. Experimental study was accomplished using a rheometer with parallel-plate geometry. Under constant stresses ranging from a small value to a large one, the resultant strains were recorded. The experimental results demonstrated that MREs behave as linear visocleastic properties. The effects of the magnetic field and stress on MRE creep behaviors were discussed. Moreover, a four-parameter viscoelastic model was developed to describe MRE creep behaviors. The comparison between the experimental results and the modeling predictions indicates that the model can predict MRE creep behaviors very well.

关键词: magneto-rheological elastomers (MREs)     creep     recovery     linear viscoelastic model    

Analysis and experiment of controllability of magnetorheological fluids based on micro-pipeline

Yongqing SU, Yikuan SONG, Jiguang YUE

《机械工程前沿(英文)》 2009年 第4卷 第3期   页码 339-344 doi: 10.1007/s11465-009-0048-3

摘要: The controllability of the magneto-rheological fluid (MRF) flowing through a micro-pipeline is analyzed. The coupled formulas for MRF are deduced by analyzing the property of the flow field and magnetic field. Then, the relationship between the flow speed of MRF and the special shear stress under the effect of the magnetic field is founded. The model of the MRF and micro-pipeline is established by using multi-physics software of Comsol, the curve of - in an ideal condition is attained by modifying parameters, and by adding the boundary condition of the model. This paper provides a theoretical proof of the controllability of MRF flowing through the micro-pipeline and explores MRF’s application on the micro-drive and control field.

关键词: Magneto-rheological fluids (MRF)     micro-pipeline     coupled model     multi-physics simulation    

Synthesis of novel magneto-hybrid polyoxometalate composite membrane with simultaneous photocatalytic

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1450-1459 doi: 10.1007/s11705-023-2310-3

摘要: Membrane technology is ideal for removing aqueous humic acid, but humic acid deposits cause membrane fouling, a significant challenge that limits its application. Herein, this work proposed an alternative approach to the controllably magnetically induced magneto-hybrid polyoxometalate (magneto-HPOM) nanocomposite migration toward the polyethersulfone (PES) membrane surface under a magnetic field to enhance the self-cleaning and antifouling functionalities of the membrane. Before incorporating magneto-HPOM nanocomposite into the PES casting solution, functionalized magnetite nanoparticles (F-MNP) were first coated with HPOM photocatalyst to fabricate a magneto-HPOM-PES membrane. It was shown that the apparent impacts of this novel magneto-HPOM-PES membrane on the hydrophilic behavior and photocatalytic properties of the magneto-HPOM nanocomposite improve the hydrophilicity, separation performance, antifouling and self-cleaning properties of the membrane compared with neat PES membrane. Furthermore, after exposure to ultraviolet light, the magneto-HPOM-PES membrane can be recovered after three cycles with a flux recovery ratio of 107.95%, 100.06%, and 95.56%, which is attributed to the temporal super hydrophilicity effect. Meanwhile, the magneto-HPOM-PES membrane could efficiently maintain 100% humic acid rejection for the first and second cycles and 99.81% for the third cycle. This study revealed a novel approach to fabricating membranes with high antifouling and self-cleaning properties for water treatment.

关键词: magneto-hybrid polyoxometalate nanocomposite     composite membrane     antifouling     self-cleaning     magnetic and photocatalytic responsiveness    

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1390-1399 doi: 10.1007/s11709-021-0775-z

摘要: High viscosity asphalt (HVA) has been a great success as a drainage pavement material. However, the larger porosity of drainage asphalt mixtures weakens the cohesion and adhesion and leads to premature rutting, water damage, spalling and cracking. The purpose of this study was to investigate the rheological properties of HVA prepared using different high viscosity modifiers through conventional tests, Brookfield viscosity tests, dynamic shear rheometer tests and bending beam rheometer tests. The conventional performance results demonstrated SBS + rubber asphalt (SRA-1/2) exhibited excellent elastic recovery and low-temperature flexibility. The 60°C dynamic viscosity results indicated TPS + rubber asphalt (TRA) had the excellent adhesion. The rotational viscosity results and rheological results indicated that SRA-2 not only exhibited excellent temperature stability and workability, as well as excellent resistance to deformation and rutting resistance, but also exhibited excellent low-temperature cracking resistance and relaxation performance. Based on rheological results, the PG classification of HVA was 16% rubber + asphalt for PG76-22, 20% rubber + asphalt for PG88-22, TRA and SRA-1/2 for PG88-28. From comprehensive evaluation of the viscosity, temperature stability and sensitivity, as well as high/low temperature performance of HVA, SRA-2 was found to be more suited to the requirements of drainage asphalt pavement materials.

关键词: high viscosity asphalt     rheological properties     rubber     modifier     viscosity    

Evaluation of a developed bypass viscous damper performance

Mahrad FAHIMINIA, Aydin SHISHEGARAN

《结构与土木工程前沿(英文)》 2020年 第14卷 第3期   页码 773-791 doi: 10.1007/s11709-020-0627-2

摘要: In this study, the dynamic behavior of a developed bypass viscous damper is evaluated. Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston. Accordingly, the viscosity coefficient of the damper can be adjusted using geometrical dimensions of the hose. Moreover, the external orifice acts as a thermal compensator and alleviates viscous heating of the damper. According to experimental results, Computational Fluid Dynamic (CFD) model, a numerical formula and the simplified Maxwell model are found and assessed; therefore, the verification of numerical and computational models are evaluated for simulating. Also, a simplified procedure is proposed to design structures with bypass viscous dampers. The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers, and it is compared with the same structure, which is designed with concentric braces and without dampers. Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements. Moreover, seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.

关键词: developed viscous damper     external orifice     energy dissipation     seismic behavior     CFD model of viscous damper     a simplified model    

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

《结构与土木工程前沿(英文)》 2012年 第6卷 第3期   页码 267-280 doi: 10.1007/s11709-012-0170-x

摘要: In this study, the structural control strategy utilizing a passive tuned mass damper (TMD) system as a seismic damping device is outlined, highlighting the parametric optimization approach for displacement and acceleration control. The theory of stationary random processes and complex frequency response functions are explained and adopted. For the vibration control of an undamped structure, the optimal parameters of a TMD, such as the optimal tuning frequency and optimal damping ratio, to stationary Gaussian white noise acceleration are investigated by using a parametric optimization procedure. For damped structures, a numerical searching technique is used to obtain the optimal parameters of the TMD, and then the explicit formulae for these optimal parameters are derived through a sequence of curve-fitting schemes. Using these specified optimal parameters, several different controlled responses are examined, and then the displacement and acceleration based control effectiveness indices of the TMD are examined from the view point of RMS values. From the viewpoint of the RMS values of displacement and acceleration, the optimal TMDs adopted in this study shows clear performance improvements for the simplified model examined, and this means that the effective optimization of the TMD has a good potential as a customized target response-based structural strategy.

关键词: tuned mass damper     parametric optimization     passive control     white noise     earthquake excitation    

Polymer nanocomposites for microactuation and magneto-electric transduction

Kaori YUSE, Benoit GUIFFARD, Rabah BELOUADAH, Lionel PETIT, Laurence SEVEYRAT, Daniel GUYOMAR

《机械工程前沿(英文)》 2009年 第4卷 第3期   页码 350-354 doi: 10.1007/s11465-009-0056-3

摘要: In the last decade, electroactive polymers have attracted much attention especially because of their very actuating capabilities. Large strain is experimentally observed, but under quite high electrical field, which can be a severe drawback for actuating applications. First part of the present paper is concerned with the reduction of applied field onto electroactive polymer films to get a given strain level. Polyurethane (PU) films filled with carbon black (CB) nanoparticles exhibit relatively high strain level under a field of only 12.5 kV/mm. The simple easy-to-make method solution cast method was applied. Even though the generated stress level is still quite low, the present work shows high strain level under quite low field appliance by easy manufacturing, lightweight, and flexible polymer film. Besides, another interest of the present paper is in magneto-elasto-electric effect of a polymer film filled with some magnetic nano particles. Films filled with nonpiezoelectric but with magnetite particles has still short history. With the use of magneto materials, a large magnetic DC bias field is generally required, and it causes big problem on application. The films filled with some magnetite nanoparticles (Fe3O4 and Nickel) are fabricated then examined. It is clearly demonstrated that our films do not require any DC bias. Although linear polarization value is relatively small, the first step of the studies on magnetite nano-filled film is presented.

关键词: electroactive polymers     carbon filling     actuator     nanocarbon     electromechanical coupling     dielectric polymer actuators     polymer actuators     microactuation     magneto-electric effect    

Influence of pressure and density on the rheological properties of rockfills

Erich BAUER, Zhongzhi FU, Sihong LIU

《结构与土木工程前沿(英文)》 2012年 第6卷 第1期   页码 25-34 doi: 10.1007/s11709-012-0143-0

摘要: Long-term deformations of rockfill dams can be related to the type of dam, the pre-compaction achieved during the construction of the dam, the history of loading events, the rheological properties of the rockfill material used, the seepage behavior caused by defects of the sealing, the interactions of the dam building with the foundation, and the hydrothermal phenomena of the stressed rockfill material. The present paper investigates the rheological properties of coarse grained rockfill materials using a hypoplastic constitutive model. Particular attention is paid to wetting deformation under different deviatoric loading states and pre-compactions. To quantify the state of weathering a so-called “solid hardness” is used in the sense of a continuum description. It is shown that an appropriate modeling of wetting deformations requires a unified description of the interaction at least between the state of weathering, the stress state, the density and the rate of deformation. The results obtained from the numerical simulations are compared with available experimental data for a rockfill material used in Xiaolangdi earth dam.

关键词: rockfills     solid hardness     wetting deformation     hypoplasticity     creep    

Preparation and rheological behaviors of PA6/SiO2 nanocompiste

WEI Shanshan, LIU Yuejun, LI Xianggang, HUANG Yugang, WANG Xiayu, ZHANG Ping

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 332-337 doi: 10.1007/s11705-007-0060-2

摘要: The polyamide 6 (PA6)/SiO nanocomposites were prepared by in situ polymerization and the rheological behaviors were investigated. The morphology of resultant materials was characterized by scanning electron microscopy (SEM) and the rheological behaviors were characterized by capillary rheometer. The results showed that the SiO particle size was around 50 nm and the particles dispersed evenly in PA6 matrix. The nanocomposites were pesudoplastic fluids and the apparent viscosities of nanocomposites increased initially and then decreased with the increase in nano-SiO content at the same temperature. The non-Newtonian indexes of nanocomposites were smaller than those of pure PA6. With the increase in nano-SiO content the apparent viscous activation energies of nanocomposites increased initially and then decreased. The rheological behaviors revealed that there were strong interactions between PA6 macromolecule chains and nano-SiO particles.

关键词: polyamide     temperature     rheological     activation     pesudoplastic    

Effects of time-varying liquid bridge forces on rheological properties, and resulting extrudability and

《结构与土木工程前沿(英文)》   页码 1295-1309 doi: 10.1007/s11709-023-0999-1

摘要: Extrudability and constructability are two important, yet contradictory issues pertaining to the construction of three-dimensional (3D) printing concrete. Extrudability is easily achieved when 3D printing cement mortar has a high water content and low cohesion, but the printed structure is easily collapsible. However, a 3D printing cement mortar with a low water content and high cohesion has a relatively stable printed structure although the cement mortar might not be extrudable. This study proposes a particle-based method to simulate 3D printing mortar extrusion and construction as an overall planning tool for building design. First, a discrete element model with time-varying liquid bridge forces is developed to investigate the microscopic effects of these forces on global rheological properties. Next, a series of numerical simulations relevant to 3D printable mortar extrudability and constructability are carried out. The study demonstrates that the effects of time-varying liquid bridge forces on rheological properties and the resulting extrudability and constructability of 3D printing mortar are considerable. Furthermore, an optimized region that satisfies both the extrusion and construction requirements is provided for 3D printing industry as a reference.

关键词: particle-based simulation     liquid bridge force     rheological property     3D printing mortar     extrudability     constructability    

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on rheological

《结构与土木工程前沿(英文)》 2023年 第17卷 第4期   页码 625-636 doi: 10.1007/s11709-023-0938-1

摘要: The research and development of high-performance pavement materials has been intensified owing to the demand for long-life pavements. This study is performed to develop a novel pavement material using waste rubber powder, waste lubricating by-product (LBP), and asphalt. Subsequently, the aging properties and aging mechanism of activated waste rubber powder modified asphalt (ARMA) are investigated based on its rheological properties and micro-characterization. The rheological results show that, compared with waste rubber powder modified asphalt (RMA), ARMA offers a higher aging resistance and a longer fatigue life. A comparison and analysis of the rheological aging parameters of ARMA and RMA show that LBP activation diminishes the aging sensitivity of ARMA. The micro-characterization result shows that the aging of ARMA may be caused by the fact that LBP-activated waste rubber powder is more reactive and can form a dense colloidal structure with asphalt. Therefore, the evaporation loss of asphalt light components by heat and the damage to the colloidal structure by oxygen during the aging process are impeded, and the thermal-oxidative aging resistance of ARMA is improved.

关键词: rubber powder modified asphalt     aging     mechanism     rheological     characterization    

Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

《结构与土木工程前沿(英文)》 2023年 第17卷 第4期   页码 606-624 doi: 10.1007/s11709-023-0925-6

摘要: A novel cambered surface steel tube damper (CSTD) with a cambered surface steel tube and two concave connecting plates is proposed herein. The steel tube is the main energy dissipation component and comprises a weakened segment in the middle, a transition segment, and an embedded segment. It is believed that during an earthquake, the middle weakened segment of the CSTD will be damaged, whereas the reliability of the end connection is ensured. Theoretical and experimental studies are conducted to verify the effectiveness of the proposed CSTD. Formulas for the initial stiffness and yield force of the CSTD are proposed. Subsequently, two CSTD specimens with different steel tube thicknesses are fabricated and tested under cyclic quasi-static loads. The result shows that the CSTD yields a stable hysteretic response and affords excellent energy dissipation. A parametric study is conducted to investigate the effects of the steel tube height, diameter, and thickness on the seismic performance of the CSTD. Compared with equal-stiffness design steel tube dampers, the CSTD exhibits better energy dissipation performance, more stable hysteretic response, and better uniformity in plastic deformation distributions.

关键词: cambered surface steel tube damper     energy dissipation capacity     finite element model     hysteretic performance     parametric study    

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 99-116 doi: 10.1007/s11709-021-0799-4

摘要: In this study, bituminous binder was modified with Cocamide Diethanolamide chemical, a non-ionic surfactant, and the physical and rheological properties of modified binders were investigated. In addition, Cocamide Diethanolamide has been used for the first time to modify bituminous binder, and this situation makes the study distinctive. Bituminous binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios (1%, 3%, and 5%). The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests (softening point, penetration, ductility) and Superpave tests (rotational viscometer, rolling thin film oven test, pressure aging vessel, dynamic shear rheometer, bending beam rheometer). In addition, the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing temperatures. In addition, compared to reference binder, rutting resistances of modified bituminous binders decreased with the increase of additive ratio. However, modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

关键词: Cocamide Diethanolamide     bitumen modification     rheology     Superpave tests    

标题 作者 时间 类型 操作

Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

期刊论文

Vibration control of a structure using Magneto-Rheological grease damper

Shinya SUGIYAMA, Tomoki SAKURAI, Shin MORISHITA

期刊论文

Creep and recovery behaviors of magnetorheological elastomers

Weihua LI, Yang ZHOU, Tongfei TIAN, Gursel ALICI,

期刊论文

Analysis and experiment of controllability of magnetorheological fluids based on micro-pipeline

Yongqing SU, Yikuan SONG, Jiguang YUE

期刊论文

Synthesis of novel magneto-hybrid polyoxometalate composite membrane with simultaneous photocatalytic

期刊论文

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

期刊论文

Evaluation of a developed bypass viscous damper performance

Mahrad FAHIMINIA, Aydin SHISHEGARAN

期刊论文

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

期刊论文

Polymer nanocomposites for microactuation and magneto-electric transduction

Kaori YUSE, Benoit GUIFFARD, Rabah BELOUADAH, Lionel PETIT, Laurence SEVEYRAT, Daniel GUYOMAR

期刊论文

Influence of pressure and density on the rheological properties of rockfills

Erich BAUER, Zhongzhi FU, Sihong LIU

期刊论文

Preparation and rheological behaviors of PA6/SiO2 nanocompiste

WEI Shanshan, LIU Yuejun, LI Xianggang, HUANG Yugang, WANG Xiayu, ZHANG Ping

期刊论文

Effects of time-varying liquid bridge forces on rheological properties, and resulting extrudability and

期刊论文

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on rheological

期刊论文

Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

期刊论文

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

期刊论文