In the applications of shock mitigation, generally speaking, the magnetorheological energy absorber (MREA) should be avoided to be excited because the viscous force generated with the motion is too high, and then a progressive current should be applied to heighten the damping force at the end of the stroke.
A novel MREA with variable multiple magnetic circuits is proposed in this paper. By simultaneously examining the motion of mechanical parts and the control circuit of the adaptive flow and magnetic design, an ideal variable magnetic distribution with four solenoid coils is obtained through magneto-flow coupled simulation. A theoretical model is deducted by integrating the Navier-Stokes equation and magnetic circuit analysis, and the factors influencing output damping force of the MREA are considered. Along with increase of piston’s route, the output damping force reaches its maximum of 7.5kN and then it decreases to 5kN and remains for a period of time which provides MREA an ability for sustainable output damping force at the end of the stroke before the motion reverses.
With this design, the penetrating force peak can be smoothed to decrease the demand of the structural strength, and this paper provides a theoretical support for the experimental validation of a high-performance MREA.
 

Stroke-related,Magnetorheological energy absorber (MREA),Navier-Stokes equation