Estudio del comportamiento de la temperatura en el flujo de los gases combustionados de un motor a gasolina en su sistema de escape mediante el ciclo de conducción PTEC-593

Abstract

The objective of this research project was to analyze the behavior of the temperature in the exhaust pipe through thermocouples before and after modifying the exhaust system based on the PTEC- 593 driving cycle. It was carried out a bibliographic review in which the operation of thermal generators and the distribution of the temperature along the exhaust pipe were determined. Thus being 4 points were selected for the study: an exhaust manifold, before the catalyst, after the catalytic converter, and at the end of the exhaust pipe. Thus, placing type K thermocouples in the exhaust system of a 1000cc vehicle, which was also modified by placing a 3-way catalyst and manufacturing a header with a 2-inch diameter pipe and SAE J403 1008 steel. The tests carried out under the driving cycle were carried out in the city of Latacunga, which is located at 2800 meters above sea level and with an average Andean climate of 12 ℃. Idle tests were also carried out at different times of the day and the last one on the route called “El Chasqui”, thus subjecting the vehicle to all kinds of possible real scenarios. As a result, temperatures above 417 ℃ were obtained in the exhaust manifold, and 310 ℃ after the catalyst with the original system, and below 160 ℃ with the header at the end of the exhaust pipe. While idling temperatures did not exceed 230 ℃. It concluded that the best point to place a thermal generator is after the catalyst because at this point it does not affect a bad reading of the lambda probe, which in turn would generate fuel consumption and high emission of polluting gases.