Abstract
The Fuel-NO_x concentrations under the conditions of high CO_2 concentration have been experimentally investigated with a tubular flame burner. At first, flame stability limits are examined for CH_4/O_2/CO_2 mixture with a tubular flame burner for non-preheating conditions as well as 300℃ preheating conditions. Results show that, for CO_2-dilution mixture, although a tubular flame can be established in wide range of Φ even under the 21% O_2 concentration condition, the stability limits can be further enhanced with the preheating of the unburned mixture. The results of NO_x measurement showed that the preheat temperature affects little on the Fuel-NO_x concentration under the fuel lean condition of Φ=0.8. The difference of the NO_x concentration for various preheat condition is within 10% for all experimental conditions.