Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
PERFORMANCE AND KNOCKING ANALYSIS OF A MOTOR GENERATOR GROUP OPERATING IN THE OTTO CYCLE WITH GASOLINE AND WATER INJECTION
Submission Author:
Vinicius Kajimoto Caetano , MG
Co-Authors:
Vinicius Kajimoto Caetano, ARTHUR MENDES, eduardo tirone, Vinicius Guerra Moreira , Marcley Pereira, Sergio Hanriot
Presenter: Vinicius Kajimoto Caetano
doi://10.26678/ABCM.ENCIT2022.CIT22-0449
Abstract
The present work approaches the accomplishment of a study about the influence of water injection, indirectly into the intake manifold, in an engine regarding the temperature of the admited air/fuel mixture, performance and reduction of the occurrence of the knocking phenomenon. To identify the phenomenon, an FFT analysis system was used through an oscilloscope. The injection of water promotes a reduction in the temperature in the combustion chamber and, consequently, a reduction in the tendency of the knocking phenomenon to occur. Therefore, when using gasoline in a dual-fuel engine, water injection makes it possible for the gasoline to operate at a higher compression ratio and closest ethanol’s, allowing the engine to work more efficiently using both fuels without the occuring of the knocking phenomenon. For the experimental tests, it was used a 1.4 engine, originally bi-fuel, 4 cylinders with a compression ratio of 10.4:1, managed by an electronically programmable injection system, operating at full load with E27 gasoline, according to ANP standards (National Petroleum Agency), and stoichiometric mixture throughout the test. The tests were carried out with the addition of different percentages of water injected into the intake manifold and it was observed that this allowed the engine to operate with greater advances in the ignition angle without the occurrence of the phenomenon of knocking, which influenced higher rotations and powers output, when compared to the engine operating without water injection. In addition, the temperatures in the intake manifold and exhaust gases were measured during the tests with and without water injection, and it was observed that greater temperature reduction were achieved in the intake of approximately 31.0°C and 30.3°C in the exhaust with 72% of water injection in relation to the mass flow of fuel. Still, a gain of 1.5 kW of output power was obtained with the highest percentage of injected water, or 6.7% in relation to the test without water injection. As for fuel consumption, it was observed that it remained constant in all tests performed.
Keywords
Water injection, Knocking, Combustion, ethanol, Flex Fuel, Brazil, Gasoline
