Influence of altitude on the height of blue cone in a premixed flame

For economic and environmental reasons natural gas begins to take an important participation as an energy source in the residential sector of Latin American cities placed at high altitudes: La Paz (3719 m), Santa Fe de Bogotá (2600 m), Mexico City (2240 m), Manizales (2150 m), Medellín (1550 m), Cali (1000 m) and others. One of the most widely used natural gas systems in the residential sector is the partially aerated burner. The height of the blue cone in a premixed flame increases as the altitude above sea level becomes greater. In this work this behavior is determined experimentally, for this purpose tests were carried out in colombian location placed at 40, 550, 1220, 2040 and 2550 m above sea level. In every place of tests three replicas were performed, keeping constant the following variables: chemical composition of natural gas, with a methane content of 98%, gas pressure discharge at the injector at 20 mbar, injector diameter in 1.35 mm, mixer geometry and port diameter in 17 mm. The images of the blue cone were captured with a Pixera digital camera for images registration. Images were stored to determine later, through the software Matrox Inspector for images analysis, the height of the blue cone in each experiment for the different altitudes. It was found that the height of the blue cone is increased in 1.49 ± 0.12 mm by each 304 m (1000 feet) rise in altitude.