Properties and application of MR fluids

Magnetorheological fluids

We carry out fundamental research in the field of magnetorheological fluids. Main areas of our research are represented by durability, flow curves, measurement of properties of magnetorheological fluids in shear mode, sedimentation, and accelerated sedimentation. We also study materials that are suitable for magnetic circuits with ultra-fast control. We further develop algorithms for effective semi-active MR systems with time response from 0.75 to 2 ms and MR dampers for specific applications.

Research characteristics

Flow characteristics of MR fluids are measured using rheometer developed at our laboratory. We are able to measure in the in-state and off-state conditions considering the shear rate up to 150 000 s-1. Rheometer can be also used as a load unit for durability tests. We have know-how about the design of MR valves and magnetic circuits as well . Along with patented ultra-fast controller, we managed to shorten time response of MR device from 20 ms down to 1 ms. We develop and test semi-active control algorithms for specific applications (from space launch vehicles to washing machines). We test and choose the most suitable materials for magnetic circuits so as they meet condition of minimal time response or maximal induction in MR valve or minimal remanence of magnetic circuit. We also focus on MR fluids sedimentation studied by accelerated tests. Other area of our research is represented by MR seals, while we are focused especially on the determination of operation parameters.

Laboratory equipment

  • Hydraulic pulsator (stroke 150 mm, max. force 40 kN and max. frequency 200 Hz)