Search results for " Combustion"
showing 10 items of 106 documents
Further Experiments on the Effect of Bulk In-Cylinder Temperature in the Pressurized Motoring Setup Using Argon Mixtures
2020
Mechanical friction and heat transfer in internal combustion engines have long been studied through both experimental and numerical simulation. This publication presents a continuation study on a Pressurized Motoring setup, which was presented in SAE paper 2018-01-0121 and found to offer robust measurements at relatively low investment and running cost. Apart from the limitation that the peak in-cylinder pressure occurs around 1 DegCA BTDC, the pressurized motoring method is often criticized on the fact that the gas temperatures in motoring are much lower than that in fired engines, hence might reflect in a different FMEP measurement. In the work presented in SAE paper 2019-01-0930, Argon w…
An Experimental Study of In-Cylinder Heat Transfer from a Pressurized Motored Engine with Varying Peak Bulk Gas Temperatures
2022
The variation of in-cylinder heat transfer with parameters such as engine speed, air-to-fuel ratio, coolant temperature and compression ratio were frequently studied in classical research. These experimentally-obtained relationships are important for improving in-cylinder heat transfer models, essential in developing CO2 reducing strategies. In this publication, a 2.0 liter compression ignition engine was tested in the pressurized motored configuration. This developed experimental setup allowed testing of the engine at speeds ranging between 1400 rpm and 3000 rpm, with peak in-cylinder gas pressures from 40 bar to 100 bar. The engine was motored using different gas compositions chosen speci…
An Effective Method to Model the Combustion Process in Spark Ignition Engines
2022
A numerical simulation is a fundamental tool in the design and optimization procedure of an Internal Combustion (IC) engine; since combustion is the process that mostly influences the engine performance, efficiency and emissions, an effective combustion submodel is fundamental. A simple, nonpredictive way to simulate the combustion evolution is to implement a mathematical function that reproduces the mass fraction burned (MFB) profile that is characterized by a sigmoidal trend; the most used for this purpose is the Wiebe function. In this article the authors propose a different mathematical model, a Dose-Response (DR) type function that shows some benefits when compared to the Wiebe functio…
Simulation Study on the Use of Argon Mixtures in the Pressurized Motored Engine for Friction Determination
2020
Mechanical friction and heat transfer in internal combustion engines are two highly researched topics, due to their importance on the mechanical and thermal efficiencies of the engine. Despite the research efforts that were done throughout the years on both these subjects, engine modeling is still somewhat limited by the use of sub-models which do not fully represent the phenomena happening in the engine. Developing new models require experimental data which is accurate, repeatable and which covers wide range of operation. In SAE 2018-01-0121, the conventional pressurized motored method was investigated and compared with other friction determination methods. The pressurized motored method p…
Realistic Steady State Performance of an Electric Turbo-Compound Engine for Hybrid Propulsion System
2022
The efficiency of Hybrid Electric Vehicles (HEVs) may be substantially increased if the unexpanded exhaust gas energy is efficiently recovered and employed for vehicle propulsion. This can be accomplished employing a properly designed exhaust gas turbine connected to a suitable generator whose output electric energy is stored in the vehicle storage system; a new hybrid propulsion system is hence delineated, where the power delivered by the main engine is combined to the power produced by the exhaust gas turbogenerator: previous studies, carried out under some simplifying assumptions, showed potential vehicle efficiency increments up to 15% with respect to a traditional turbocharged engine. …
WAVES PROPAGATION AND LIQUID ALUMINUM PARTICLE INJECTION IN SOLID ROCKET MOTORS
2013
A method to determine the injection of aluminium particles from the solid propellant burning surface to the core of the chamber in the presence of an acoustic wave field is developed and aluminum-droplet effects on propagation of acoustic waves in the flow of a solid rocket motor are analysed. Changes of the multiphase flow compressibility are calculated by taking into account both the translational and the pulsational motions of the aluminum droplets in consequence of the acoustic waves.
Detailed Combustion Analysis of a Supercharged Double-Fueled Spark Ignition Engine
2021
The main goal of researches in the field of automotive engineering is to obtain a large-scale implementation of low- or zero-emissions vehicles in order to substantially reduce air pollution in urban areas. A fundamental step toward this green transition is represented by the improvement of current internal combustion (IC) engines in terms of fuel economy and pollutant emissions. The spark ignition (SI) engines of modern light-duty vehicles are supercharged, down-sized, and equipped with direct injection. Gaseous fuels, such as liquefied petroleum gas (LPG) or natural gas (NG), proved to be a valid alternative to gasoline in order to reduce pollutant emissions and increase fuel economy. In …
In-Cylinder Heat Transfer Determination Using Impulse Response Method with a Two-Dimensional Characterization of the Eroding Surface Thermocouple
2021
Heat transfer from the cylinder of internal combustion engines has been studied for decades, both in motored and fired configurations. Its understanding remains fundamental to the optimization of engine structures and sub-systems due to its direct effect on reliability, thermal efficiency and gaseous emissions. Experimental measurements are usually conducted using fast response surface thermometers, which give the instantaneous cylinder surface temperature. The transient component of heat flux through the cylinder wall was traditionally obtained from a spectral analysis of the surface temperature fluctuation, whereas the steady-state component was obtained from Fourier's law of conduction. …
Fluidized Bed Combustion and Gasification of Fossil and Renewable Slurry Fuels
2021
This article provides a comprehensive review of the state of the art and more recent developments of the thermochemical treatments of slurry fuels in fluidized beds (FB). The review focuses on FB combustion and gasification of slurry fuels based on coal, biomass, sludge, and wastes from industry, agriculture, and the civil sector. The investigations at research and industrial levels over the last decades are presented and discussed, highlighting the adopted technological solutions, the results in terms of feasibility and efficiency, and the perspectives of future development. The different behavior between bubbling and circulating beds was addressed, in particular the optimal choice dependi…
Modelling the Interaction between Air Pollutant Emissions and Their Key Sources in Poland
2021
The main purpose of this study is to investigate the relationships between key sources of air pollutant emissions (sources of energy production, factories which are particularly harmful to the environment, the fleets of cars, environmental protection expenditure) and the main environmental air pollution (SO2, NOx, CO and PM) in Poland. Models based on MLP neural networks were used as predictive models. Global sensitivity analysis was used to demonstrate the significant impact of individual network input variables on the output variable. To verify the effectiveness of the models created, the actual data were compared with the data obtained through modelling. Projected courses of changes in t…