RESEARCH OF THE INTAKE VALVE DEACTIVATION ON ENGINE PERFORMANCE

In this paper, the effect of the Intake Valve Deactivation (IVDA) on engine performance is investigated in detail. Based on an optimization platform with Genetic Algorithm (GA) and engine thermodynamic model, the characteristics of the engine volumetric efficiency and pumping loss were studied under the cam-drive, Single Intake Valve (SIV) and Dual Intake Valves (DIV) operating modes, and the effect of the IVDA on the engine fuel economy was revealed with taking the power consumption of the Electromagnetic Actuated Valvetrain (EAVT) system into consideration. Then, switch rules for the SIV and DIV mode was proposed, and the switching boundary conditions between them were confirmed. Finally, the optimal intake valve close timings for the EAVT system were obtained. Results show that, under the low speed conditions, the SIV mode has little influence on the engine volumetric efficiency, while within the high speed conditions the effect of the IVDA on the volumetric efficiency is significant; compared with the traditional cam-drive valvetrain, the pumping loss of the EAVT engine decreases significantly and shows unique characteristics due to the use of the EIVC strategy; with the use of the IVDA scheme, the energy consumption of the EAVT system reduces, but the engine pumping loss increases in the meantime, both balance their influence on the engine fuel economy. In general, the IVDA scheme is preferred if the engine volumetric efficiency can be ensured, otherwise, the DIV mode takes priority over the SIV mode to maintain the engine power performance.