Magnetorheological (MR) fluids can be utilized in one of the fundamental operating modes of which the gradient pinch mode has been the least explored. In this unique mode non-uniform magnetic field distributions are taken advantage of to develop a so-called Venturi-like contraction in MR fluids. By adequately directing magnetic flux the material can be made solidified in the regions near the flow channel wall, thus creating a passage in the middle of the channel for the fluid to pass through.
View Article and Find Full Text PDFThe transient behaviour of magnetorheological (MR) devices is an important parameter for modern semi-actively controlled suspension systems. A significant part of the MR device response time is the MR fluid response time itself. A significant factor is the so-called rheological response time.
View Article and Find Full Text PDFThis article presents a list of suitable techniques and materials leading to the design of an ultra-fast magnetorheological (MR) valve. Two approaches for achieving the short response time are proposed: (a) by means of material, and (b) by means of the shape. Within the shape approach, the revolutionary technique of 3D metal printing using a selective laser melting (SLM) method was tested.
View Article and Find Full Text PDFThe paper focuses on the coefficient of friction (COF) of a magnetorheological fluid (MRF) in the wide range of working conditions across all the lubrication regimes-boundary, mixed, elastohydrodynamic (EHD), and hydrodynamic (HD) lubrication, specifically focused on the common working area of MR damper. The coefficient of friction was measured for MR fluids from Lord company with concentrations of 22, 32, and 40 vol. % of iron particles at temperatures 40 and 80 °C.
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