مقاله انگلیسی رایگان در مورد شبیه سازی عددی یک دمپر سیال مگنتورهولوژیکی کوچکتر – الزویر ۲۰۱۸

In order to develop a smaller magnetorheological fluid (MRF) damper and its corresponding analysis software, a new MRF damper with outer-coils and testing system was designed. The testing results show that the MRF has good mechanical properties when the damping gap is 1.5mm. The smoothing damping force is only 1.0-4.0N by adjusting the coil current from 0A to 2A, and it is linearly related to current through data fitting. The damping force versus velocity curve has obvious hysteresis characteristic, and an improved nonlinear dynamic model is proposed. Based on the model and linear function, electromechanical characteristics of the MRF damper can be simulated by Simulink, which provides an analysis platform for applications of the damper.

INTRODUCTION

With the emergence of new intelligent materials and the wide use of semi-active control technology, magnetorheological technology attracts more and more attention of researchers. Magnetorheological fluid (MRF) is mainly composed of soft magnetic particles, mother liquor and additives to prevent the settling of the mixture of particles [1-4]. Under the condition of magnetic field, the MRF can transform from free-flowing liquid to highly viscosity, low-flow Bingham fluid in millisecond time, and the change is continuous and reversible, the yield strength is controllable [5-8]. It is the intelligence and stability, making the MRF has received extensive attention in the field of science and technology in recent years, which to a certain extent promoted the development of the semi-active control [9-12]. Among all the application of using magnetorheological technology, the MRF damper based on magnetorheological effect is a semi-active control device with good performance. It has the advantages of simple structure, fast response, large dynamic range, good durability and strong reliability [13-15]. In reality, MRF dampers are mostly used in heavy machinery, construction, medical, and bridge cables nowadays [16].For example, the United States Lord Corporation developed a full-scale MRF damper whose output of damping force up to 180kN [17], even the smaller MRF damper such as MR101097, its minimum output of damping force also reached 100N [18]. It is not suitable for some applications where the force needed less than 100N, not to mention of meeting the soft landing force of less than 10N required for flip chip bonding of microelectronics packaging [19-24]. So, the smaller damping system needs to be developed and the appropriate analysis software needs to be researched for practical application. Therefore, this study was undertaken to design a smaller MRF damper to obtain the output of damping force of less than 4N. The electromechanical property of MRF damper was tested by the test equipment. Based on the experimental data, the general equation of the output damping force was deduced, and the model was simulated by Simulink. Design and experiment 1) Structure Design of the micro MRF damper According to the different motion modes of the MRF in damper, MRF damper is generally divided into four types: shear type, valve type, shear valve type and squeeze valve type [25-27]. Because the shear valve type possesses both the advantages of shear type and valve type, its output adjustable damping force has a large range, and the design of magnetic circuit is simple. Therefor, the design of MRF damper adopted shear valve type. For the miniature damper system, the general inner winding mode cannot be manufactured and assembled, therefore, a novel outer winding type was used in this miniature damper system.