The Design And The Research Of Magnetorheological Fluid Brake

Magnetorheological Fluid is an intellectual material with good prospect,usually composed of mother fluid that can't transmit magnet and uniformly distributed magnetic micro granules in it. When the strength of the magnetic field reaches a certain index,notable magnetorheological effect take place in the magnetorheological fluid with good characteristic. That is to say the attribute of the fluid is changed from liquid to solid. The time of the change is extremely short and the change is recurrent.Aiming at the current research situation that our automotive brake manufacture level is lower,this article puts forward a new idea designing MRP Brake,and introduces material composition and rheological mechanics of MRF.Rheological mechanics of MRP is compared with ERF,Extensive attention has been paid to MRP because of their high yield stress.The yield stress of MRP is generally one order of magnitude large than that of ERF in equivalent conditions. The yield stress of the MRF is more than 60kpa under a magnetic fields of 3 X 105A/m.Working principle,performance target of brake and defect of mechanical plate and drum type brakes in modern cars are introduced:Designing two type MR brakes that actual application is good . The working principle and basic structure of the MR Brakes are analyzed and the torque calculating model is established and test bench of the MR brake is designed. Through changing MR brake working diameter parameters,distance parameters and temperature and etc. Brake torque change of the MR brake is set out.Conclusions can be drawn from the graph of brake torque change of the MRP brake:Using different MRP,the brake torque varied very much;with the same working diameter,the same width of working face and the same distance,the brake torque of plate MRP brake is bigger than that of cylindrical MRF brake;In a certain range of temperature,temperature has little effect on the brake torque;while working diameter and working distance of the brake has obvious effect on the brake torque,so in the design,these two parameter should be emphasized.The results indicate that the structure design of the MRF Brake is applicable,it supplied theoretical foundation and experimental basis for actual application of MRP brake.