scholarly journals Development of a novel MR clutch featuring tooth-shaped disc

2021 ◽  
Vol 43 (3) ◽  
pp. 265-276
Author(s):  
Quoc Hung Nguyen ◽  
Bao Tri Diep ◽  
Duy Hung Nguyen ◽  
Van Bien Nguyen ◽  
Van Bo Vu ◽  
...  
Keyword(s):  
Air Gap ◽  
Experimental Results ◽  
Optimization Process ◽  
Introductory Part ◽  
Braking Torque ◽  
Experimental Works ◽  
Magneto Rheological ◽  
The Right ◽  
Magnetic Poles ◽  
Good Agreement

In this research, we focus on development of a new configuration of magneto-rheological fluid (MRF) based clutch (MRC) featuring a tooth-shaped disc with multiple teeth acting as multiple magnetic poles of the clutch. The tooth-shaped disc is placed in a clutch housing composed of the left housing and the right housing. The inner face the housing also has tooth shaped features mating with the teeth of the disc through the working MRF. Excitation coils are placed directly on stationary winding cores placed on both side of the clutch housing. An air gap of 0.3 mm is left between the housing and the winding cores to ensure the housing can freely rotate against the winding cores. After the introductory part, configuration of the MRC is introduced and the transmitted torque of the MRC is derived. An optimization process to minimize the overall volume of the proposed clutch, which can generate a required maximum braking torque, is then conducted. The optimal results show that the overall volume of the proposed MRC is significantly reduced compared to a referenced conventional MRC (0.159 m3 vs. 0.295 m3). A prototype of the proposed MRC is fabricated for experimental works and good agreement between the experimental results and simulated ones is archived.

Development of Magnetorheological Brake with Tooth-Shaped Disc for Small Size Motorcycle

2019 ◽  
Vol 889 ◽  
pp. 508-517
Author(s):  
Duc Thang Le ◽  
Ngoc Diep Nguyen ◽  
Duy Tuan Le ◽  
Ngoc Tuyen Nguyen ◽  
Van Vinh Pham ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Finite Element Analysis ◽  
Element Analysis ◽  
Braking Performance ◽  
Trapezoidal Shape ◽  
Braking Torque ◽  
New Type ◽  
Magneto Rheological ◽  
Magnetic Poles ◽  
Multiple Poles

In this research, a new type of magneto-rheological brake (MRB) is proposed for small size motorcycle. The proposed MRB consists of a rotor with multiple trapezoidal teeth acting at multiple magnetic poles of the brake. In order to generate a magnetic field for controlling braking torque, a magnetic coil is placed on each side-housing of the brake. The inner face of each side-housing also has trapezoidal shape mating with the trapezoidal teeth of the rotor via MRF layer. By applying countercurrents to the coils, a magnetic fluid is generated with some magnetic flux going across the MRF layer (MRF duct) between the rotor teeth and their mating poles on the housing. By using multiple poles with trapezoidal shape, a high braking torque of the brake is expected while the size of the brake is still kept to be compacted. After an introduction about the development of MRBs in automotive engineering, the configuration of the proposed MRB is presented and its braking torque is derived based on Bingham rheological model of MRF. The proposed MRB is then optimally designed based on finite element analysis (FEA). Its optimized MRB is then manufactured and its braking performance is experimentally investigated. The MRB is then installed in a prototype motorcycle and the field test of this prototype motorcycle integrated with the MRB is then conducted.

Structure Simulation and Performance Test of Flexible Fixture Based on Magneto-Rheological Fluids

2014 ◽  
Vol 1027 ◽  
pp. 246-250
Author(s):  
Jun Jin Ma ◽  
Ding Hua Zhang ◽  
Bao Hai Wu ◽  
Ming Luo
Keyword(s):  
Magnetic Field ◽  
Performance Test ◽  
Great Influence ◽  
Experimental Results ◽  
External Compression ◽  
Mr Fluids ◽  
Structure Simulation ◽  
And Performance ◽  
Magneto Rheological ◽  
Good Agreement

To solve the precision manufacturing of thin-walled irregular-shaped workpiece, the MR fluids flexible fixture was designed and the simulation of device with compression structure was carried out to obtain performance parameters of device for optimizing the device. Then, some experimental test was implemented to verify the feasibility of device. The simulation and experimental results show that the current and coil turns have a great influence on magnetic field, and the shear stress of MR fluids are related with magnetic field and external compression force. The experimental results are in good agreement with simulation ones.

Design and experimental evaluation a novel magneto-rheological brake with tooth-shaped rotor

2021 ◽  
Author(s):  
Van Bien Nguyen ◽  
Hiep Dai Le ◽  
Quoc Hung Nguyen ◽  
Do Qui Duyen ◽  
Do Huu Minh Hieu ◽  
...  
Keyword(s):  
Optimal Design ◽  
Power Consumption ◽  
Thin Wall ◽  
Element Analysis ◽  
Single Coil ◽  
Compact Size ◽  
Braking Torque ◽  
Working Principle ◽  
Magneto Rheological ◽  
Magnetic Poles

Abstract In this study, a novel magnetorheological brake (MRB) with tooth-shape rotor is developed. In this new MRB, traditional cylindrical rotor is replaced by a new one with tooth-shaped rotor. The teeth on the rotor act as multiple magnetic poles of the brake. Two magnetic coils are placed on side-housings of the brake to generate a mutual magnetic field of the MRB. The inner face of each side-housing has tooth shaped features as well. These tooth shaped features interact with the rotor teeth via magnetorheological fluid (MRF) medium. By using the tooth shaped rotor, more interface area between the rotor and the working MRF can be archived, which can improve performance characteristics of the proposed MRB such as compact size, low power consumption and high torque. After an introduction of state of the art of MRB development, the schematics and working principle of the MRB with tooth-shaped rotor is proposed. The modeling of the MRB is then derived based on magnetic finite element analysis (FEA) and Bingham rheological model of MRF. Optimal design of the MRB considering mass and braking torque of the MRB is then conducted. From the optimal design result, it is shown that the mass and power consumption of the proposed MRB are significantly smaller than those of previously developed ones. In details, at high value of the maximum braking torque (100Nm), the proposed MRB mass is only around 31.3% of the mass of the thin-wall single-coil and 42.6% of the mass of the thin-wall double coil MRB. In addition, at small values of the maximum braking torque (5Nm), power consumption of the proposed MRB is only around 33% of that of the thin-wall single-coil and 45.5% of that of the thin-wall double coil MRB. Experimental works on prototypes of the proposed MRB are then performed for validation.

Design and investigation of a novel magnetorheological brake with coils directly placed on side housings using a separating thin wall

2021 ◽  
pp. 1045389X2199391
Author(s):  
Ngoc Diep Nguyen ◽  
Tan Tien Nguyen ◽  
Dai Hiep Le ◽  
Quoc Hung Nguyen
Keyword(s):  
Magnetic Circuit ◽  
Outer Part ◽  
Thin Wall ◽  
Improve Performance ◽  
Element Analysis ◽  
Bingham Plastic ◽  
Braking Torque ◽  
Experimental Works ◽  
Magneto Rheological ◽  
Inner Parts

This research focuses on a new design to facilitate the manufacturing and improve performance of magneto-rheological brake (MRB). In this proposed MRB, the coils are directly placed on inner part of the side housing of the MRB and separated with the working MR fluid by a thin wall. The coils are then covered by the outer part of side housing to form a closed magnetic circuit. With this configuration, the coils do not directly contact with the MRF therefore a very small MRF gap size can be archived. In addition, the coils can be assembled and disassembled in the housing without separating the inner parts of the housing out of the disc. This makes a lot of convenience in fabrication, testing and maintenance of the MRB. After a review of MRB development, configuration of the proposed MRB is presented. Braking torque of the proposed MRB is then derived based on Bingham-plastic rheological model of MRF. Based on finite element analysis, optimal design of the proposed MRB is then conducted. The results are then compared with other types of MRB to figure out the advanced performance characteristics of the proposed one. In order to validate simulated results, prototypes of the proposed MRBs are manufactured and experimental works are then conducted.

Inducing Frictional Force to Enhance the Transient Response in Beams

2019 ◽  
Vol 22 (2) ◽  
pp. 88-93
Author(s):  
Hamed Khanger Mina ◽  
Waleed K. Al-Ashtrai
Keyword(s):  
Numerical Analysis ◽  
Transient Response ◽  
Frictional Force ◽  
Damping Ratio ◽  
Experimental Results ◽  
Damping Capacity ◽  
Tightening Force ◽  
Contact Areas ◽  
Good Agreement ◽  
Ansys Workbench

This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.

PHOTOINDUCED NONLINEAR OCTUPOLAR POLARIZATION: TRANSIENT AND PERMANENT REGIMES

1996 ◽  
Vol 05 (04) ◽  
pp. 653-670 ◽  
Author(s):  
CÉLINE FIORINI ◽  
JEAN-MICHEL NUNZI ◽  
FABRICE CHARRA ◽  
IFOR D.W. SAMUEL ◽  
JOSEPH ZYSS
Keyword(s):  
Theoretical Analysis ◽  
Second Harmonic ◽  
Experimental Results ◽  
Polar Field ◽  
Rotational Spectrum ◽  
Dual Frequency ◽  
One Dimensional ◽  
Ethyl Violet ◽  
Disperse Red 1 ◽  
Good Agreement

An original poling method using purely optical means and based on a dual-frequency interference process is presented. We show that the coherent superposition of two beams at fundamental and second-harmonic frequencies results in a polar field with an irreducible rotational spectrum containing both a vector and an octupolar component. This enables the method to be applied even to molecules without a permanent dipole such as octupolar molecules. After a theoretical analysis of the process, we describe different experiments aiming at light-induced noncentrosymmetry performed respectively on one-dimensional Disperse Red 1 and octupolar Ethyl Violet molecules. Macroscopic octupolar patterning of the induced order is demonstrated in both transient and permanent regimes. Experimental results show good agreement with theory.

scholarly journals Comparison of Experimental and Numerical Transient Drop Deformation during Transition through Orifices in High-Pressure Homogenizers

2021 ◽  
Vol 5 (3) ◽  
pp. 32
Author(s):  
Benedikt Mutsch ◽  
Peter Walzel ◽  
Christian J. Kähler
Keyword(s):  
High Pressure ◽  
Visual Analysis ◽  
Imaging Technique ◽  
Extensional Flow ◽  
Droplet Breakup ◽  
Experimental Results ◽  
Drop Deformation ◽  
Droplet Deformation ◽  
Shadow Imaging ◽  
Good Agreement

The droplet deformation in dispersing units of high-pressure homogenizers (HPH) is examined experimentally and numerically. Due to the small size of common homogenizer nozzles, the visual analysis of the transient droplet generation is usually not possible. Therefore, a scaled setup was used. The droplet deformation was determined quantitatively by using a shadow imaging technique. It is shown that the influence of transient stresses on the droplets caused by laminar extensional flow upstream the orifice is highly relevant for the droplet breakup behind the nozzle. Classical approaches based on an equilibrium assumption on the other side are not adequate to explain the observed droplet distributions. Based on the experimental results, a relationship from the literature with numerical simulations adopting different models are used to determine the transient droplet deformation during transition through orifices. It is shown that numerical and experimental results are in fairly good agreement at limited settings. It can be concluded that a scaled apparatus is well suited to estimate the transient droplet formation up to the outlet of the orifice.

Simulation of Sphere’s Motion Induced by Shock Waves

2012 ◽  
Vol 134 (10) ◽  
Author(s):  
Dan Igra ◽  
Ozer Igra ◽  
Lazhar Houas ◽  
Georges Jourdan
Keyword(s):  
Shock Waves ◽  
Drag Coefficient ◽  
Drag Force ◽  
Stationary Flow ◽  
Experimental Results ◽  
Experimental Findings ◽  
Sphere Drag ◽  
Simulation Scheme ◽  
Good Agreement

Simulations of experimental results appearing in Jourdan et al. (2007, “Drag Coefficient of a Sphere in a Non-Stationary Flow: New Results,”Proc. R. Soc. London, Ser. A, 463, pp. 3323–3345) regarding acceleration of a sphere by the postshock flow were conducted in order to find the contribution of the various parameters affecting the sphere drag force. Based on the good agreement found between present simulations and experimental findings, it is concluded that the proposed simulation scheme could safely be used for evaluating the sphere’s motion in the postshock flow.

Viscoelastic Deformation of PC/ABS Alloy

2007 ◽  
Vol 353-358 ◽  
pp. 1229-1232
Author(s):  
Z.N. Yin ◽  
L.F. Fan ◽  
Tie Jun Wang
Keyword(s):  
Dynamic Mechanical Analysis ◽  
Relaxation Modulus ◽  
Mechanical Analysis ◽  
Experimental Results ◽  
Viscoelastic Deformation ◽  
Dynamic Mechanical ◽  
Storage And Loss Moduli ◽  
Static Relaxation ◽  
Comparison Of The Results ◽  
Good Agreement

Dynamic Mechanical Analysis (DMA) and static relaxation tests are carried out to study the viscoelastic deformation of PC/ABS alloy with blending ratio of PC to ABS being 50/50. A modified approach is developed to calculate the relaxation modulus of PC/ABS alloy from the DMA experimental results of storage and loss moduli. Comparison of the results obtained from DMA and static relaxation tests is presented and good agreement is found.

Simulation and experimentation of a magnetorheological brake with adjustable gap

2016 ◽  
Vol 28 (12) ◽  
pp. 1614-1626 ◽  
Author(s):  
Wan-Li Song ◽  
Dong-Heng Li ◽  
Yan Tao ◽  
Na Wang ◽  
Shi-Chao Xiu
Keyword(s):  
Magnetorheological Fluid ◽  
Structure Design ◽  
Experimental Results ◽  
Wear Property ◽  
Braking Performance ◽  
Braking Torque ◽  
The Difference ◽  
The Impact ◽  
Theoretical Analyses ◽  
Magnetostatic Simulation

The aim of this work is to investigate the effect of the small magnetorheological fluid gap on the braking performance of the magnetorheological brake. In this article, theoretical analyses of the output torque are given first, and then the operating principle and design details of the magnetorheological brake whose magnetorheological fluid gap can be altered are presented and discussed. Next, the magnetic circuit of the proposed magnetorheological brake is conducted and further followed by a magnetostatic simulation of the magnetorheological brakes with different sizes of fluid gap. A prototype of the magnetorheological brake is fabricated and a series of tests are carried out to evaluate the braking performance and torque stability, as well as the verification of the simulation results. Experimental results show that the braking torque increases with the increase in the current, and the difference for the impact of the fluid gap on braking performance is huge under different currents. The rules, which the experimental results show, have an important significance on both the improvement of structure design for magnetorheological brake and the investigation of the wear property under different fluid gaps.

Sign in / Sign up

Export Citation Format

Share Document