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| Author(s): |
Jair Leopoldo Loaiza Bernal
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica |
| Defense date: | 2019-04-16 |
| Examining board members: |
Janito Vaqueiro Ferreira;
José Eduardo Mautone Barros;
Pedro Teixeira Lacava;
Waldyr Luiz Ribeiro Gallo;
Rogério Gonçalves dos Santos
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| Advisor: | Janito Vaqueiro Ferreira |
| Abstract | |
In the continuous search for the increase in efficiency and the reduction of environmental impact, due to the use of internal combustion engines (ICE), water injection has been one of the strategies frequently used to achiev these objectives. Several have been and still are the methodologies that use water as a method of temperature control and emission reduction. Before the use of jet turbines and during the use of piston engines in military and commercial aviation, the injection of water and water and alcohol solutions was implemented as a strategy to control the internal temperature of the cylinder during combustion. This allowed the increase of compression ratios with the consequent increase in power, especially in critical operations such as takeoff and evasive maneuvers during the fighting. The consequences of the application of this technique have been extensively investigated in engines that use fuels derived from petroleum (Gasoline and Diesel). However, in devices that use alternative fuels such as ethanol or other bio-fuels, there are few references to research that uses water injection techniques in these engines. The research presented here shows the results of the implementation using computational simulation of a thermodynamic model of two zones that integrates the injection of liquid water directly into the combustion chamber, in an engine that uses ethanol as fuel. The proposed model interprets from thermodynamics the behavior of the water inside the cylinder when it is injected in liquid form during any moment of the cycle. So far, this type of analysis has been carried out through experimental tests. Here the influence of water from the theoretical point of view is studied using simulation. The model is validated by comparing its results with those of experimental research that implements the same water injection technique that is proposed. The research mentioned uses a prototype engine that uses gasoline as fuel. When comparing some of the operating parameters, such as the pressure inside the cylinder, the specific fuel consumption at brake or the rate of heat release during combustion, it is found that the model behaves very closely to what was reported in the experimental data. Other variables such as NOx emissions present similar trends between experimental and simulated behavior, despite the great variability of the experimental data. Finally, the model presents great flexibility because it can be used to simulate different engine geometries, rotation regimes and the use of fuels such as gasoline, ethanol, hydrated ethanol and mixtures of these in different proportions (AU) | |
| FAPESP's process: | 15/20801-3 - Study of the operation of the internal combustion engine fueled by ethanol with addition of water to the combustion chamber |
| Grantee: | Jair Leopoldo Loaiza Bernal |
| Support Opportunities: | Scholarships in Brazil - Doctorate |