PERFORMANCE ANALYSIS OF AN ENGINE MOUNT FEATURING ER FLUIDS AND PIEZOACTUATORS

1996 ◽  
Vol 10 (23n24) ◽  
pp. 3143-3157 ◽  
Author(s):  
S.H. CHOI ◽  
Y.T. CHOI ◽  
S.B. CHOI ◽  
C.C. CHEONG
Keyword(s):  
Electric Field ◽  
Frequency Domain ◽  
Control Technique ◽  
Operating Frequency ◽  
Frequency Range ◽  
Engine Mounts ◽  
Operating Frequency Range ◽  
Engine Mount ◽  
Er Fluids ◽  
Er Fluid

Conventional rubber mounts and various types of passive or semi-active hydraulic engine mounts for a passenger vehicle have their own functional aims on the limited frequency band in the broad engine operating frequency range. In order to achieve high system performance over all frequency ranges of the engine operation, a new type of engine mount featuring electro-rheological(ER) fluids and piezoactuators is proposed in this study. A mathematical model of the proposed engine mount is derived using the bond graph method which is inherently adequate to model the interconnected hydromechanical system. In the low frequency domain, the ER fluid is activated upon imposing an electric field for vibration isolation while the piezoactuator is activated in the high frequency domain. A neuro-control algorithm is utilized to determine control electric field for the ER fluid, and H∞ control technique is adopted for the piezoactuator Comparative works between the proposed and single-actuating(ER fluid only or piezoactuator only) engine mounts are undertaken by evaluating force transmissibility over a wide operating frequency range.

MOLECULAR ORIENTATION AND ELECTROHYDRODYNAMIC FLOW IN HOMOGENEOUS ER FLUIDS

2001 ◽  
Vol 15 (06n07) ◽  
pp. 973-979 ◽  
Author(s):  
HIROKI IWATSUKI ◽  
NAOTO GOHKO ◽  
HIROSHI KIMURA ◽  
YUICHI MASUBUCHI ◽  
JUN-ICHI TAKIMOTO ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Electric Field ◽  
Molecular Orientation ◽  
Liquid Crystalline ◽  
Polypropylene Glycol ◽  
Homogeneous Fluid ◽  
Immiscible Liquids ◽  
Electrohydrodynamic Flow ◽  
Er Fluids ◽  
Er Fluid

Homogeneous ER fluid is an ER fluid which consists of a homogeneous fluid only; it is neither a suspension nor a blend of immiscible liquids. Various liquid crystals are typical examples of homogeneous ER fluids. Recently, we have found that urethane-modified polypropylene glycol (UPPG) is one of the very few examples of homogeneous ER fluids which show no liquid crystalline order. In order to clarify the mechanism of the ER effect in this fluid, we have studied, in this paper, electrohydrodynamic flow under shear and electric field.

THE FREQUENCY DEPENDENCE AND NON-LINEAR DIELECTRIC PROPERTY OF ER FLUID

1996 ◽  
Vol 10 (23n24) ◽  
pp. 3073-3080 ◽  
Author(s):  
KUNQUAN LU ◽  
WEIJIA WEN ◽  
CHENXI LI
Keyword(s):  
Dielectric Property ◽  
Field Strength ◽  
Electric Field ◽  
Frequency Dependence ◽  
Threshold Value ◽  
Shear Stresses ◽  
Linear Behavior ◽  
Non Linear ◽  
Er Fluids ◽  
Er Fluid

The frequency dependence of the shear stress in ac field and the non-linear dielectric property of ER fluid have been studied. We find that the shear stresses of some water-free ER fluids increase monotonously with the frequency and tend to reach saturated values at high frequency. The measurements on KNbO 3/silicone ER fluid show that the shear stresses under 103 Hz frequency a.c. field are several times or even an order larger than that under d.c. field for the same field strength. The studies of non-linear dielectric properties of ER fluids show that the permittivity of ER fluid increases linearly with increasing field strength when the electric field exceeds a threshold value E 1 and tends to a saturated constant beyond a high field strength E 2. Correspondingly the current density follows linear behavior no longer in the region between E 1 and E 2. A model based on the rearrangement of the particles under the electric field. which causes the variation of the dielectric property of the ER fluid, is proposed and the analysis is consistent with the measured results.

Extracting Maximum Power in the Presence of Internal Inductance of Electromagnetic Energy Harvesting Systems

2020 ◽  
Author(s):  
Yamini Sharma ◽  
Lei Zuo
Keyword(s):  
Energy Harvesting ◽  
Electromagnetic Energy ◽  
Maximum Power ◽  
Operating Frequency ◽  
Frequency Range ◽  
Low Frequencies ◽  
Internal Inductance ◽  
Piezoelectric Energy ◽  
Operating Frequency Range ◽  
Electromagnetic Energy Harvesting

Abstract In this paper, the effect of internal inductance of electromagnetic generators in the field of energy harvesting is discussed. Electromagnetic energy harvesters are typically operated at low frequencies. This results in the generator internal inductor impedance being significantly less than the generator internal resistance. However, at high frequencies, this inductance can no longer be ignored. Therefore, to maximize the harvested power, the internal inductance must be considered while designing the power electronics. This paper presents two methods to tackle this issue. The first method involves making use of a discrete capacitor which is able to reduce the inductance effect not just at resonant frequency but for the entire operating frequency range. The second method makes use of a concept similar to synchronized switching harvesting on inductors (SSHI) in piezoelectric energy harvesting. A capacitor and switch are added in the electromagnetic energy harvesting circuit to reduce the generator internal inductance effect. This method not only provides the benefit of performing well in the entire operating frequency range but also eliminates the need for precise maximum power tracking techniques, which further helps in reducing the circuit losses. Simulation results show a maximum power output increase of 56%.

ELECTRIC-FIELD-INDUCED PHASE SEPARATION IN ELECTRORHEOLOGICAL FLUIDS

1994 ◽  
Vol 08 (20n21) ◽  
pp. 2811-2822 ◽  
Author(s):  
XIN-LU TANG ◽  
KE-QIN ZHU ◽  
E. GUAN ◽  
XIAO-PING WU
Keyword(s):  
Phase Separation ◽  
Electric Field ◽  
Strong Electric Field ◽  
Processing System ◽  
Video Camera ◽  
Two Dimensional ◽  
Critical Fields ◽  
Computer Image Processing ◽  
Er Fluids ◽  
Er Fluid

The phase separation into a high-density and a low-density phase, which occurs after a strong electric field is applied to an ER fluids, is demonstrated in terms of the Coulomb interaction energy of the system. The phase separation is manifested by two-dimensional pattern observed in the field direction by means of a pair of transparent glass (TG) electrodes. The development of phase separation with an increasing field is recorded by a computer image processing system consisting of a CCD video camera. The patterns are irregular and their characteristic sizes are determined by two-dimensional auto-correlation approach. The dependency of those patterns on external electric field is analyzed based on statistical methods. Two critical fields are presented to characterize the electric-field-induced phase separation process in the ER fluid.

Effect of Urea Content on Properties and Microstructure of Ni/TiO2 Group Particles ER Fluid

2012 ◽  
Vol 496 ◽  
pp. 25-29 ◽  
Author(s):  
Suo Kui Tan ◽  
Xiao Ping Song ◽  
Hong Zhao ◽  
Song Ji ◽  
Hong Yan Guo ◽  
...  
Keyword(s):  
Electric Field ◽  
Mass Ratio ◽  
Microstructure Observation ◽  
Urea Content ◽  
Column Structure ◽  
Dc Electric Field ◽  
Er Fluids ◽  
Er Fluid

This paper emphasis have researched the effect of Ni/TiO2group particles modifier with Urea by properties and microstructure，it has showed that ER activity of the particles were closely associated with urea content. When the mass ratio of urea/Ti is 30%, The microstructure observation of the ER fluids under DC electric field showed that the particles aggregated to form thicker and dense column structure when the mass ratio of Urea/Ti is 30%, while the column structure were broken when excessive urea (>30%) was added. A thin and loose column structure was formed in non-urea added ER fluid.

scholarly journals Гибридный металлополимер как потенциальная активная среда оптоакустического генератора

2022 ◽  
Vol 48 (3) ◽  
pp. 36
Author(s):  
Е.И. Гиршова ◽  
Е.П. Микитчук ◽  
А.В. Белоновский ◽  
К.М. Морозов
Keyword(s):  
Silver Nanoparticles ◽  
Active Medium ◽  
Hybrid Material ◽  
Volume Fraction ◽  
Silver Content ◽  
Thermodynamic Characteristics ◽  
Operating Frequency ◽  
Frequency Range ◽  
Volume Fractions ◽  
Operating Frequency Range

A hybrid material was studied, consisting of polydimethylsiloxane and silver nanoparticles distributed throughout its volume, its optical and thermodynamic characteristics were calculated for different volume fractions of silver content. It is theoretically shown that this material with a volume fraction of silver of about 30% can be used as an active medium for an optoacoustic transducer with an operating frequency range of about 10 MHz.

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