Model of behaviour of magnetorheological fluids to analyse the preyield

M. Zubieta - M. J. Elejabarrieta - M. M. Bou-Ali

Mondragon University, Loramendi 4 20500 Mondragon, Spain

Abstract
In this work a double yield stress model that describes the behaviour of magnetorheological (MR) fluids is presented. The first yield stress is elastic and the second yield stress is viscous, defining an initial elastic behaviour and posterior biviscous behaviour. The model presented has been validated by experimental tests realized using a rotational rheometer equipped with a parallel plates measuring system. In these tests, the preyield behaviour has been studied with detailed interest. The experimental tests show that the tested MR fluid has an initial solid-like behaviour and a posterior liquid-like behaviour, therefore, the proposed model shows a good agreement with the experimental results. Figs 6, Refs 8.