Papers by Tomás Arriagada Moreno
Future emission regulation requires drastic reductions of harmful regulated pollutants from large... more Future emission regulation requires drastic reductions of harmful regulated pollutants from large diesel engines. For marine diesel engines, especially the recently adopted amendments to MARPOL Annex VI, contains significantly tightened regulations in terms of emission control for both existing and new engines.
Emulsions of diesel and water are often promoted as being able to overcome the difficulty of simu... more Emulsions of diesel and water are often promoted as being able to overcome the difficulty of simultaneously reducing emissions of both oxidises of nitrogen (NO x ) and particulate matter from diesel engines. In this paper we present measurements of the performance and NO x and hydrocarbon emissions of a diesel engine operating on a typical diesel oil emulsion and examine through the use of heat release analysis differences found during its combustion relative to standard diesel in the same engine. While producing similar or greater thermal efficiency and improved NO x and hydrocarbon emission outcomes, use of the emulsion also results in an increase in brake specific fuel consumption. Use of the emulsion is also shown to result in a retarded fuel injection, but smaller ignition delay for the same engine timing. As a result of these changes, cylinder pressures and temperatures are lower.
Compression ignition engines used as marine engines are the most efficient internal combustion en... more Compression ignition engines used as marine engines are the most efficient internal combustion engines. They are well-established products, and millions are already on the market. Water-in-MDO (marine diesel oil) emulsions are the best alternative fuel for compression ignition engines and can be utilised with the existing setup of 2.0 L automotive common rail direct injection (CRDI) engines. They have benefits for the simultaneous reduction of both NO x and smoke (black carbon). Furthermore, they have a significant impact on the improvement of combustion efficiency. Micro-explosions are the most important phenomenon of water-in-diesel emulsions inside an internal combustion engine chamber. They affect both the emission reduction and combustion efficiency improvements directly and indirectly in accordance with the brake mean effective pressure (BMEP) and rpm. Owing to the influence of micro-emulsions on the combustion and emissions of water-in-diesel emulsion fuel, the reduction ratios of NO x and smoke in a used engine are approximately 30% and 80%, respectively. The effect of the operating parameters on micro-emulsions is presented.
Due to its impact on human health and the nature surrounding us, diesel engine emissions have bee... more Due to its impact on human health and the nature surrounding us, diesel engine emissions have been significantly reduced over the last two decades. This reduction has been enforced by the legislating organizations around the world that gradually have made the manufacturers transform their engines to today's complex high-tech products. One of the most challenging area to meet the legislations is the emissions of the diesel engines which are the products of the combustion of diesel fuel. More restrictions have been imposed by some governments to reduce these emissions to a level such that will not cause any harmful impacts for the environment after releasing them to the atmosphere. This paper examines the effects of combusting a mixture of diesel fuel, water, and surfactant which forms emulsion on the nitrogen oxides NOx, carbon monoxide CO, carbon dioxide CO2, sulfur oxides SOx emissions and particulate matter (PM) from a compression ignition (CI) or diesel engine. Previous research has attributed the observed reduction of these emissions to a suppression of the flame temperature due to quenching effects from the water, thereby reducing thermal NOx formation and other pollutants. The focus of this review paper will be on experiments were previously conducted using a diesel engine with pure diesel fuel and compare it to the emulsion of water-diesel. Furthermore, results from the testing diesel fuel that mixed with varied ratios of water balanced with a surfactant to stabilize the emulsion will be presented and discussed. Three different samples of water-diesel emulsion were used with 10 % water and 90 % diesel, 20 % water and 80% diesel, and 30 % water and 70 % diesel (by volume) respectively to conduct the experiments in the lab. The purpose was to see the impact of adding the water from 10 % up to 30 % (by volume) to the diesel fuel making the emulsified fuel to investigate the impacts on the emissions and the performance of the engine. The data shows a significant NOx emission reduction when using the emulsion water diesel fuel in the range from 20% to 30 % water (by volume) in diesel. These results are correlated with a thermodynamic first law analysis to estimate the adiabatic flame temperature of the standard fuel and fuel-water emulsion cases. Results indicate that thermal NOx is indeed reduced by quenching and flame temperature suppression confirming reports in the literature. Recommendations are given for further studies, including improving the fuel-water emulsion and considerations for long-term testing.
Página 3 ANEXO I: Reglas 24-26, Apéndices I -III, Interpretaciones unificadas del ANEXO I y Apénd... more Página 3 ANEXO I: Reglas 24-26, Apéndices I -III, Interpretaciones unificadas del ANEXO I y Apéndices 1-7 de las interpretaciones unificadas Página 4 ANEXO I: Apéndices 8-9 de las interpretaciones unificadas ANEXO II: Reglas 1-15
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Papers by Tomás Arriagada Moreno