Combustion control - variable valve timing for internal combustion engines

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Objectives: Internal Combustion (IC) engines are used in practically all vehicle applications with an estimated 800 million vehicles worldwide in 2005. One goal of my research is to improve the thermal efficiency and reduce harmful emissions of spark ignition IC engines, reducing greenhouse gases and improving air quality. Homogeneous Charge Compression Ignition(HCCI): can reduce both fuel consumption and some exhaust pollutants. HCCI holds the potential for Diesel like fuel efficiency with low NOx and low particulate emissions. In HCCI combustion a homogeneous air-fuel mixture auto-ignites without a spark. HCCI has a premixed charge like a spark-ignition engine but the ignition is triggered by the chemical kinetics similar to a diesel engine. The goals of my research are to increase the fundamental understanding of HCCI combustion by generating unique experimental data useful for themokinetic simulation models, and to develop computational tractable models that can be used to develop strategies to control HCCI combustion. Thermodynamic analysis and experimental investigation of variable valve timing on a single cylinder spark ignition internal combustion engine running HCCI will be performed. Solenoid Valve Control: Solenoid valve actuators controlling the intake and exhaust valve timing in IC engines make it possible to investigate novel thermodynamic cycles. Completely flexible valve timing is one way to meet the precise in-cylinder mixture requirements for HCCI combustion. Electromagnetic solenoid valves are a practical way to obtain variable valve timing and allow for each cylinder charge to be controlled for each combustion event but require feedback motion control to achieve the low valve seating velocity needed for engine wear and noise requirements. To meet stringent valve landing speed requirements, non-linear end control will be combined with adaptive control methods.