Combustion characteristics of dual swirl low nitrogen burners in small gas boilers

Swirl combustion technology is an effective method for achieving low nitrogen (low \mathrm{NO_x} ) combustion. In this study, we designed a dual-swirl low \mathrm{NO_x} burner with the goal of minimizing \mathrm{NO_x} emissions. and the burner was evaluated in a 20 tonne per hour gas boiler through numerical simulation and experimentation. Swirl angles and excess air coefficients (1.0-1.20) of the burner were tested within the range of 1.0-1.2. The results indicated that the optimal swirl plate angles were 35? internally and 55? externally. The optimal excess air coefficient was 1.15, which balances heat transfer efficiency and minimize \mathrm{NO_x} emissions. Results show that the dual swirl combustion system can effectively reduce nitrogen oxide emissions in small gas boilers.