Gregory M. Shaver

Learn More
Homogeneous charge compression ignition (HCCI) is a novel combustion strategy for IC engines that exhibits dramatic decreases in fuel consumption and exhaust emissions. Originally conceived in 1979, the HCCI methodology has been revisited several times by industry but has yet to be implemented because the process is difficult to control. To help address(More)
With stated benefits ranging from increased thermal efficiency to significantly reduced NOx emissions, Homogeneous Charge Compression Ignition (HCCI) represents a promising combustion strategy for future engines. When achieved by reinducting exhaust gas with a variable valve actuation (VVA) system, however, HCCI possesses nonlinear cycle-to-cycle coupling(More)
In an effort to reduce dependence on petroleum-based fuels and increase engine efficiency, fuel-flexible engines with advanced technologies, including variable valve timing, are being developed. Fuel-flexible spark-ignition engines permit the increased use of ethanol–gasoline blends. Ethanol, an alternative to petroleum-based gasoline, is a renewable fuel,(More)
Homogeneous Charge Compression Ignition (HCCI) represents a promising combustion strategy for future engines. However, HCCI lacks an easily identified combustion trigger and, when achieved via variable valve actuation (VVA), includes cycle-to-cycle coupling through the exhaust gas. This makes controlling the process decidedly non-trivial. To address these(More)
Advanced combustion modes, such as PCCI, operate near the system stability limits. In PCCI, the combustion event begins without a direct combustion trigger in contrast to traditional spark-ignited gasoline engines and direct-injected diesel engines. The lack of a direct combustion trigger necessitates the usage of model-based controls to provide robust(More)
Homogeneous Charge Compression Ignition (HCCI) is a promising low temperature combustion strategy for internal combustion engines. However, when HCCI is achieved with variable valve actuation (VVA) the lack of a direct combustion initiator and cycle-to-cycle dynamics complicate control of the process. This work outlines a strategy for the simultaneous(More)
Modeling and control of the gas exchange process in modern diesel engines is critical for the promotion and control of advanced combustion strategies. However, most modeling efforts to date use complex stand-alone simulation packages that are not easily integrated into, or amenable for the synthesis of, engine control systems. Simpler control-oriented(More)
Magee, Mark E. M.S.M.E., Purdue University, May 2014. Exhaust Thermal Management using Cylinder Deactivation and Late Intake Valve Closing. Major Professor: Gregory M. Shaver, School of Mechanical Engineering. Progressively stricter emission regulations have compelled diesel engine manufacturers to develop new technologies that reduce harmful pollutants(More)