Virtual engine calibration exploiting fully-physical plant models is the most promising solution for the reduction of time and cost of the traditional calibration process based on experimental testing. However, accuracy issues on the estimation of pollutant emissions are still unresolved. In this context, the paper shows how a virtual test rig can be built by […]
Enhancing mixture preparation upstream of the premixed autoignition zone is a solution to reduce soot emission formation in compression ignition engines. With this aim, in recent years, Ducted Fuel Injection (DFI) concept has been developed: DFI is based on the idea of injecting the fuel spray through a small cylindrical pipe within the combustion chamber […]
The reduction of CO2 emissions, and hence of fuel consumption, is currently a key driver for the development of innovative SI engines for passenger car applications. In recent years, motorsport technical regulations in the highest categories have seen the introduction of limits concerning the fuel flow rate and the total amount of fuel per race, […]
The introduction of innovative spark ignition engines featuring extreme downsizing, high compression ratio and Miller Cycle has led to an increasing interest in water injection as one of the most promising countermeasures to reduce the knock risk. In this paper, the potential of a Port Water Injection (PWI) system integrated in a state-of-the-art turbocharged downsized […]
The development of innovative diesel piston bowl designs has shown significant improvement of the near-wall flame evolution, resulting in lower fuel consumption and engine-out soot emissions. With this aim, a novel hybrid piston bowl for a 1.6 L light-duty diesel engine was designed, coupling a sharp-stepped bowl and radial-bumps in the inner bowl rim. The […]
Computational Fluid Dynamics (CFD) with Large Eddy Simulation (LES) turbulence model is a valuable tool to investigate complex problems. However, for high Reynolds number problems, the associated huge computational cost often leads researchers to the use of more simplified and less accurate approaches, especially if statistics is needed for the generalization of the results and […]
Pre-chamber (PC) ignition systems, enabling Turbulent Jet Ignition (TJI) combustion, represent a promising technology to extend the lean limit of Spark Ignition Internal Combustion Engines. Indeed, the higher ignition energy provided by the turbulent jets contributes to the limitation of combustion duration and variability even in diluted conditions. However, a detailed analysis of the combustion […]
The diesel combustion research is increasingly focused on ducted fuel injection (DFI), a promising concept to abate engine-out soot emissions in compression-ignition engines. A large set of experiments carried out in constant volume vessel and numerical simulations, at medium-low computational cost, showed that the duct adoption in front of the injector nozzle activates several soot […]
