Compressible magnetorheological fluid damper (Conference Presentation)

Abstract

Dynamic performance of a compressible magnetorheological fluid (CMRF) damper with an asymmetric damping performance was examined. Due to the 400°F operational environment , a high-temperature silicone damping fluid was utilized as the base of the CMRF. The CMRF damper valve was designed and optimized using two-dimensional axisymmetric electromagnetic finite element analysis. A secondary piston that incorporates check valves was attached to the CMRF valve, which provides the asymmetry under jounce and rebound. The CMRF damper utilizes a twin tube structure, whereas the space between the inner and outer tubes was used as a high-pressure accumulator for operation at elevated temperatures. Up to a certain temperature, the designed CMRF damper acts as a liquid spring, whereas after certain in-chamber pressure is exceeded, the CMRF damper behaves as a conventional damper. Dynamic characterization of the CMRF damper was performed under sinusoidal excitation for velocities up to 1.27 m/s (50 in/s). This study also examined the CMRF damper under several different environmental conditions including, humidity, salt fog, extreme temperatures and sand exposure. It was demonstrated that the CMRF damper can provide asymmetric and controllable rebound and compression forces. It was also shown that the selected components such as CMRF base fluid, seals and electromagnet wires can withstand the several different operating conditions.