Abstract: The temperature rise model of magnetorheological(MR) dampers is investigated to eliminate or minimize the effect of high temperature on their damping characters. Based on the temperature rise principle of MR dampers, two different temperature rise models are developed under the large amplitude sine excitation, respectively. According to simplified one-dimensional equation of heat transfer through a fluid element, one model is developed on the MR fluid within MR dampers and is fit for MR dampers with thick-wall hydraulic cylinder, and the predicted temperature is higher than the test temperature. The other model is developed on the MR damper, and corresponding predicted temperature is lower than the test temperature. Solutions of model equations are derived for the temperature rise within the damper as a function of time to predict the temperature range within MR dampers. An experiment result shows the tested temperature is in the range of predicted temperatures. According to structural parameters of MR dampers, the proper theory model is chosen to predict the temperature in practical applications, or an exact solution can be obtain with two different temperatures weighted mean.

Key words: Damper, Heat transfer, Magnetorheological fluid, Temperature rise