Stability and emissions control using air injection and H2 addition in premixed combustion

The effects of composition on burning velocity and nitric oxide formation in laminar premixed flames of CH4 + H2 + O2 + N2

“…In a laboratory-scale swirl burner, replacing natural gas by hydrogen while keeping the sum 0010 of the volumetric fuel flow rate constant caused increase of soot, NO x , and CO in exhaust gases [10]. In a backward-facing step combustor with H 2 addition to propane, exhaust NO x concentrations were found to be higher, which was explained by the overall burning temperature increase [6]. In methane + hydrogen + air flames stabilized over a perforated plate burner at 1 atm, the NO concentrations were measured at a fixed distance from the burner [11].…”

“…This concept is based on the extension of the flammability limits toward fuel-lean conditions where the emission of nitrogen oxides is significantly reduced [1][2][3][4][5][6]. Numerical simulations [7,8] showed that if the equivalence ratio is kept constant, the addition of hydrogen to lean counterflow methane + air flames increases the emission of NO, but also significantly enlarges the flammable region.…”

Fuel flexibility, stability and emissions in premixed hydrogen-rich gas turbine combustion: Technology, fundamentals, and numerical simulations

“…Several groups experimentally investigated NO x emissions when the fuel composition is modified in both diffusion [119,120], and premixed flames [121][122][123][124][125][126]118,125], in real gas turbine scale as well as laboratory scale configurations. Although the specific NO x emission level observed for lab-scale configurations may not be representative of a full scale device, the trends however can be considered indicative of the performance in real systems.…”

“…Ghoniem et al [121] explored the addition of H 2 to C 3 H 8 in a step combustor. In this configura cross-section height of 22.9 mm ation strong flame-vortex interactions occur immediately after the step and constitute the mechanism of heat release dynamics of the flow.…”

Experiments on heat content inside a Rijke tube with suppression of thermo-acoustics instability

“…35 Some control techniques in open-loop form have also been found equally promising. For example, injection of air upstream of the flame either at steady rate [36][37][38] or at low-frequency pulsating rate. 32,33 The present study describes a control technique which uses radial injection of a small quantity of air through micro-jets into the flame close to the burnerhead in a Rijke tube model.…”