Simulation And Experimental Investigation Of Magnetic-rheological Brake

Magnetorheological(MR)fluid is a new type of smart materials,and its rheological property can be changed rapidly by applying a magnetic field,hence the rapid response of the rheological property makes it has been further investigated and widely used in industry.At the same time,the conventional hydraulic brake(CHB)system has a series of limitations and defects due to its structural properties,such as the response delay,wear,the requirement of some auxiliary structures(such as hydraulic pump,pipeline and tank etc.)which can increase the cost and quality of the brake system.Due to the excellent rheological properties of MR fluid,the MR brake resolves many pain points of CHB system,and thus it has significant practical and economic benefits for the investigation of MR brake.This article mainly focus on the simulation and experimental investigation for MR brake,including the establishment of the mathematical model of MR brake based on different constitutive equations of MR fluids,electromagnetic and temperature field simulation,and the friction and wear test of braking disc of the MR brake.The main contents of this work include the following:(1)According to the relevant literatures,the development status and research progress of MR fluids and MR brakes are systematically reviewed at home and abroad,at the same time,the MR effect and the influencing factors of MR properties are summarized.(2)According to the Herschel-Bulkey and Bingham constitutive equation of MR fluid proposed by foreign scholars,the output torque models of disc and drum type MR brake were established and the kinetics of the brake were analyzed.(3)In this work,a disc-type MR brake with adjustable working gap was developed.Therefore,the effect of working gap size and applied current on the braking torque was simulation and experimental studied based on the proposed MR brake.(4)In order to calculate the distribution of temperature field of the MR brake under different working gaps,the simulation of temperature field was carried based on the proposed MR brake.Then,a multi-channel temperature acquisition system consists of K type thermocouple and Arduino Mega 2560 microcontroller was established based on the test bed,and the experimental data validated the simulation results,which provides certain reference for the structure optimization of MR brake.(5)The friction and wear properties of braking disc within the MR brake was investigated by the proposed MR brake,the wear loss and the method of scanning electron microscopy(SEM)technique were used corporately to further investigate the wear mechanism.