Investigation on the Combustion Characteristics and Environmental Effects of Hydrogen-doped Natural Gas for Domestic Water Heaters.

The addition of hydrogen to natural gas is an effective approach to broaden the range of applications for hydrogen and address the issue of global warming. However, the inclusion of hydrogen alters the combustion properties of natural gas. The paper established a simplified mechanism consisting of 19 components and a 67-step reaction for hydrogen-doped natural gas combustion. With this simplified mechanism, the effects of hydrogen doping and the utilization of porous media combustion techniques on the combustion characteristics of natural gas were investigated numerically. The results suggested that the utilization of porous media combustion technology is beneficial for achieving the complete combustion of hydrogen-doped natural gas and reducing pollutant emissions. Additionally, the total gas cost and environmental impact of domestic gas water heaters with hydrogen-doping natural gas were estimated. The findings show that the use of 20% hydrogen-doped natural gas contributes to a decrement in fuel costs and reduced emissions of CO by 25.4%, NO by 53.9%, and CO by 6.78%.