Performance investigation of an SI engine with variable valve timing and lift based on a magneto-rheological valve

Cylinder valve with variable timing and variable lift is a potential technology to improve engine performance. This research studied cylinder dynamics of a spark-ignition (SI) engine equipped with a new full variable valve system (VVS) based on an innovated magneto-rheological (MR) technology. An MR valve block was combined with a conventional inlet valve in this MR VVS. The study obtained many patterns of valve opening/closing by controlling current to the MR VVS, which controlled the MR fluid flowing through magnetic plate block. Magnetic simulations were performed for the new MR VVS to investigate the relationships among MR valve displacement, valve lift, and valve timing. Simulation results showed that the MR VVS provided high degrees of freedom of valve timing and lift for gasoline engine to produce different torque modes and high engine efficiency. The abilities of this MR VVS to become essential technique of high-efficiency engine were confirmed in the results.