Gregory M. Shaver

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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 NO x emissions, Homogeneous Charge Compression Ignition (HCCI) represents a promising combustion strategy for future engines. When achieved by rein-ducting exhaust gas with a variable valve actuation (VVA) system , however, HCCI possesses nonlinear cycle-to-cycle(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)
A diode-laser-absorption-spectroscopy-based sensor system was used to perform high-speed (100 Hz to 5 kHz) measurements of gas properties (temperature, pressure, and H(2)O vapor concentration) at the turbocharger inlet and at the exhaust gas recirculation (EGR) cooler exit of a diesel engine. An earlier version of this system was previously used for(More)
and Nielsen D (2015) Impact of cylinder deactivation on active diesel particulate filter regeneration at highway cruise conditions. Heavy-duty over-the-road trucks require periodic active diesel particulate filter regen-eration to clean the filter of stored particulate matter. These events require sustained temperatures between 500 and 600°C to complete the(More)