A method for modeling Electro-Rheological (ER) dampers is proposed. It consists in two sequential steps: Characterization and Customization. Both steps are. This study presents nondimensional analysis of an Eyring constitutive model to describe the field-dependent behavior of an electrorheological. This paper presents the design, analysis, testing and modeling of an electrorheological (ER) fluid damper developed for vibration and seismic.
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The error-to-signal Ratio ESR performance index was used to evaluate the model accuracy. The major efforts have been aimed at parametric models.
The Choi electrorrheological Eyring-plastic models present smaller forces than the customized model. This model also produces larger compression forces with large displacements. Experiments and have a greater ESR index when compared with the ones achieved in experiments andrespectively.
Depending on the physical characteristics of the ER damper, 3a3b are customized so that only the required terms are considered to preserve an accurate representation while simplifying the model structure, Table 2. Furthermore, the yield stress is field dependent; it increases as the electric field does.
This combination is feasible when the fluid within the dampers is replaced with electrorheological fluid. From the FV diagram, Figure 6 ait can be seen that this ER damper is asymmetrical; the maximum force in extension positive velocity is greater than the force generated in compression negative velocity.
Passive suspension systems are tailored to achieve a tradeoff of electrorheologkcal objectives [ 1 ]. None of the analyzed models consider the stick-slip effect so the force peaks around 0. The resulting model has low computational complexity. The first one is the most common, the cylindrical type, in which the ER fluid flows through an annular channel where the electric field is applied.
In the FD diagram, Figure 6 ban abnormal stick-slip appears as a peak, as well as effect of the frequency in the damper stiffness. The method was experimentally validated with a commercial damper. Electrorheilogical passive FV and FD experimental diagrams, Figures 5 a and 5 bare analyzed and the following characteristics can be identified: At the yield point the damper fluid behavior changes from a pseudoplastic to a quasisolid [ 17 ].
Name University of Notre Dame. The yield point defines where the SA damper operates: In the FV diagram the yield point is a Cartesian point where the damping force becomes independent of the velocity.
In order to analyze the effectiveness of the customized model, a comparative analysis with other two well-known models was carried out: In the FD diagram the experimental data presents higher density with small forces, especially in compression, Figure 12 e. Characteristic diagrams of the ER damper passive behavior.
These results were also validated with two-dimensional density plots. Mathematical Problems in Engineering. This damper presents significant hysteresis in all its operational range, being more notorious at low speed and in positive velocity.
In Figures 8 b and 9 electrorhoelogical it can be seen that the model can represent the rigidity of the damper, but in the same way as in Figures 9 a electrorheologicwl 10 a the stick-slip phenomenon appears again. In the experimental FV diagram, Figure 12 athe higher density of data appears with small compression forces while in the Choi model, Figure 12 bthe higher density appears with larger forces; hence, this model represents a stiffer damping force than the real damper at low velocities.
Also at low speed the hysteresis loop in SA force is not significant, but as the velocity and the PWM duty cycle rise, the hysteresis rises too, Figure 7 a. This model represents the hysteretic behavior of the ER damper in postyield zone and its increment due to the frequency, but the assessment of the model is done with constant conditions of frequency displacement and electric field.
An electrorheological fluid vibration damper – IOPscience
The proposed method does not need a priori knowledge i. The results of this test are presented in Table 7and each point is the average of 3 replicas of the test. The model parameters were fitted using the LSE method. This method requires experimental data of the ER damper. Also, at the postyield zone, an average force gain FM is obtained, based on the average value in which the yield of the force occurs at each manipulation value.
The experimental system and Design of Experiments are shown in the next section. Comparison of estimated green and experimental black data based on.
Method for Modeling Electrorheological Dampers Using Its Dynamic Characteristics
The ER damper force can be represented by two components: Experiments were designed to explore the nonlinear behavior of the damper at different frequencies and actuation signals i. Since the terms related with the hysteresis have been taken out from the model, when the hysteresis is predominant, the customized model is not able to reproduce the force as correct as the full model. To receive news and publication elsctrorheological for Mathematical Problems in Engineering, enter your email address in the box below.
In contrast with the experimental data, in the Eyring-plastic model the higher density electrorheo,ogical with large forces and exhibits a saturation, Figure 12 g ; hence the Eyring-plastic model produces smaller forces with large displacements than the real damper. Subscribe to Table of Contents Alerts. However, most of them are highly dependent on internal physical properties of the damper usually confidential informationdemand too much computational effort, or fail to capture the nonlinear behavior of the ER damper.
The customized model ends with a short equation with high performance. The ER fluid, when exposed to the electric field, behaves as a viscoelastic material, known as a Bingham plastic.