Design of Semi-active Magnetorheological Valve

This paper presents a methodology of design of a semi-active magnetorheological (MR) valve. The MR valve has been used successfully for a long period of time in many technical applications. When the valve is used as a semi-active element, problems occurred. The application of this valve is limited, mainly due to the slow response time and its low dynamic range. The methodology consists of flow analysis of a non-Newtonian fluid and FEM analysis of a magnetic circuit. A parallel-plate model was used together with Bingham fluid to describe the flow in the valve. A static and transient model of the magnetic circuit was solved by the FEM program Maxwell. The semi-active MR valve design was based on the presented methodology. In our research the magnetic circuit was made from ferrite that significantly reduces the response time of the magnetic field. The valve was designed only to operate only until the velocity at the breaking point of the F-v curve. Therefore, now there is a large dynamic range in this area. It is reasonable to expect that the designed modifications of the MR valve allow us to use this technology in semi-active suspension systems.