Experimental study on the flame radiation fraction of hydrogen and propane gas mixture

Abstract

Hydrogen added to hydrocarbon fuels can improve the combustion efficiency and reduce soot emissions. However, there are some safety problems with the storage and transportation of the hydrogen and hydrocarbon fuel gas mixture. In order to investigate the combustion characteristics of gas mixture, the propane and hydrogen are used as the fuel gas in this study. A series of experiments have been carried out to investigate the radiation fraction of the turbulent diffusion jet flame under ambient conditions (300 K, 1 bar). The experimental results showed that the dilution effect of hydrogen is limited for propane when the hydrogen flow rate is small. The radiation fraction changes slightly with the increase in the flow rate of hydrogen under the same heat release rate of propane. And then, it decreases sharply when the ratio of hydrogen volume flow rate to total flow rate is larger than 0.6. Based on the theoretical analysis of laminar combustion velocity, activationenergy, and the soot generation theory, a dimensionless model has been developed to describe the evolution of radiation fraction.