Flameless Combustion with Liquid Fuels for Ultra-Low Emissions from Combustion Systems

Abstract

This chapter presents the detailed computational and experimental investigations on the flameless combustion of liquid fuels to achieve ultra-low NOx emissions from combustion systems employed for various applications such as industrial furnaces and gas turbines. Initially, in this chapter, the overview of the progress in flameless combustion with liquid fuels is reported. In the later sections of this chapter, design and development of a novel flameless combustor is reported for the applications in gas turbines. A unique air injection scheme is used to achieve increased levels of recirculation. The combustor operates with kerosene for thermal intensities varying from 10-20 MW/m3. It is reported that increased recirculation with the help of a new air injection method helps achieve flameless combustion. Reactant dilution ratio, Rdil , is used to quantify the recirculation in flameless combustion mode. It reaches a value of Rdil ~3.75 for specific operating conditions of thermal input and equivalence ratio. The measurements of temperature, gaseous emissions, heat flux are reported for different operating conditions of thermal inputs and equivalence ratios. Measured NOx emissions approach zero value for a specific range of operating conditions.