Dilute operation of a SI engine offers attractive performance incentives. Lowered combustion temperatures and changes in the mixture composition inhibit NOx formation and increase the effective value ....
As natural gas engines are designed to operate leaner and with increased boost pressure, durability of the spark plugs becomes problematic. Among the various new ignition devices that have been consid....
As part of ongoing research on hydrogen-enhanced lean burn SI engines, this paper details an experimental combustion system optimization program. Experiments focused on three key areas: the ignition s....
Exhaust Emissions from lean burn natural gas engines may not always be as low as the potential permits, especially engines with open loop lambda control. These engines can produce much higher emission....
It is a very challenging problem to reliably ignite extremely lean mixtures, especially for the low speed, high load conditions of large-bore natural gas engines. If these engines are to be use for th....
An extensive comparison of laser-induced ignition and spark plug ignition of lean methane-air mixtures was performed. Experiments were carried out under engine-like conditions in a high pressure, cons....
Ultra lean-burn natural gas engines offer the potential for lower emissions and higher efficiency than conventional SI engines. Combustion instabilities near the lean limit can be addressed by partial....
This paper presents a parametric, experimental study of the performance of gas and liquid propane injection in a spark ignition, multi-point port injected (MPI) engine. An inline, six cylinder engine ....
The burned-gas propagation process has been characterized in two bi-fuel engines by means of a combustion diagnostic tool resulting from the integration of an original multizone heat-release model wit....
The anti-knock or octane quality of a fuel depends on the fuel composition as well as on the engine design and operating conditions. The true octane quality of practical fuels is defined by the Octane....
Today's engine and combustion process development is closely related to the port layout. Combustion and emission performance are coupled to the intensity of turbulence, the quality of mixture formatio....
This present work is aimed to the analysis of the possible advantages that could be obtained exploiting Variable Valve Actuation strategies in an high performance engine head. A set of experimental te....
This note focuses on the three fundamental mechanisms behind premixed flame-turbulence interactions that result in progressive acceleration of a spark-ignited flame in a turbulent environment such as ....
A new combustion method of high compression ratio SI engine was studied and proposed in order to achieve higher thermal efficiency of SI engine comparable to that of CI engine. Compression ratio of SI....
The auto-ignition or anti-knock quality of a practical fuel is defined by the Octane Index, OI = (1-K)RON + KMON where RON and MON are the Research and Motor Octane numbers and K is a constant dependi....
The main objectives of this investigation are the visualisation of the flame propagation depending on different boundary conditions. Turbulence intensities, wall-temperatures and an air-fuel ratios we....
An experimental activity aimed to analyze the noise emission of a small gasoline engine equipped with two spark plugs per cylinder was performed. A custom electronic device permitted to set the delay ....
Steady state emissions testing on a dynamometer with an 11-liter heavy-duty engine have shown the ability to obtain tail pipe oxides of nitrogen (NOx) emissions of 0.15 g/bhp and below. Equivalence ra....
Understanding the nitric oxide (NO) conversion process plays a major role in optimizing the Selective NOX Recirculation (SNR) technique. SNR has been proven in gasoline and diesel engines, with up to ....
The On-Board Distillation System (OBDS) extracts, from gasoline, a highly volatile crank fuel that enables simultaneous reduction of start-up fuel enrichment and significant ignition timing retard dur....
