Optimal design and experimental evaluation of magneto-rheological mount applied to start/stop mode of vehicle powertrain

Abstract

Magneto-rheological mount is one of the most effective vibration isolation devices for the vibration isolation system of vehicle powertrain. In this article, a flow type of magneto-rheological mount was proposed to control the vibration and the torque excitation of the engine when vehicle was in start/stop mode. A mathematical model for the flow type of magneto-rheological mount was formulated with consideration of the influence of current on magneto-rheological fluid viscosity and the relationship between liquid resistance effect and flow rate in damping gap. Then, a co-simulation optimal platform was developed by the Isight and the ANSYS, and the non-dominated sorting genetic algorithm II was used to optimize magnetic circuit. Subsequently, two prototypes of magneto-rheological mounts were manufactured according to the initial design and the optimal design model, and the dynamic performance test of magneto-rheological mount monomer and the vibration isolation performance test of the whole vehicle under start/stop mode were carried out, respectively. The experimental results showed that the controllability and the vibration isolation performance of the optimal design magneto-rheological mount were significantly improved compared with the initial design.

Design and multi-objective optimization of magnetorheological damper considering vehicle riding comfort and operation stability

“…Where C 1 and C 2 are the modified coefficient, when Nguyen et al, 2013). L 1 = L 2 , t y is the shear yield stress, which affects the damping force through the magnetic flux density (Deng et al, 2020).…”

Magnetic circuit design and optimisation of magnetorheological mount with tapered channel under the flow mode

“…Where R 1 is the inner diameter of the inner magnetic core, L is the height of the magnetic core, H 0 is the gap width of the damping channel, q is flow rate in damping channel and h is the fluid viscosity without an applied magnetic field. The yield pressure drop is expressed as (Deng et al, 2020): Where L 1 is the effective magnetic pole length and L 1 = L 2 , and t y is the shear yield stress. The total pressure drop of the radial flow channel is:…”

Dynamic characterization of controlled multi-channel semi-active magnetorheological fluid mount

“…A p is the equivalent cross-sectional area of the upper chamber, C 1 and C 2 are the volume flexibility of the upper and lower chambers, P 1 and P 2 are the pressure of the upper and lower chambers, and Q r denotes the flow rate of the fluid through the rate-dip channel. Assuming that the flow of fluid through the rate-dip channel is laminar and that the inlet losses can be neglected, the fluid inertia and fluid resistance flowing through the rate-dip channel are I r and R r , respectively, and the solution expression is as follows (Doebelin, 1998).…”

“…At present, mounts used for engine vibration isolation can be divided into rubber mounts, hydraulic mounts, semi-active mounts, and active mounts. Compared to rubber mounts, hydraulic mounts (Fan, 2006) improve noise, vibration, and harshness (NVH) performance at low frequency, but the greater dynamic stiffness at high frequency due to hardening is not conducive to noise reduction. Active mounts can achieve better NVH performance in a wider band under automotive driving conditions, but their complex structure and high cost are only used in a few luxury vehicles (Hausberg et al, 2015;Römling et al, 2003;Fan et al, 2020).…”