The analysis of temperature and air entrainment rate for the turbulence diffusion jet flame of propane and carbon dioxide gas mixture.

A few of studies have investigated the temperature profile and air entrainment of the turbulent jet diffusion flame produced by the combustion of a gas mixture. In this study, the air entrainment rate and temperature distribution along the axis of a turbulent jet diffusion flame of propane mixed with different concentrations of carbon dioxide were therefore investigated, which using a series of experiments conducted with 2, 3, and 4 mm nozzles. The results show that the flame temperature increased in the continuous flame region and decreased in fire plume region as the carbon dioxide concentration increased under the same heat release rate. A virtual origin model was then developed to analyze the relationship between carbon dioxide concentration and flame temperature. The air entrainment rate of the fire plume region was influenced by the gas flow speed from the nozzles, and the total air entrainment rate was inversely proportional to the carbon dioxide concentration. A correlation among the flame temperature, carbon dioxide concentration, and air entrainment rate was then established, providing a valuable resource for the risk assessment of turbulent jet diffusion flames. • The temperature is proportional to CO 2 concentration in continuous flame region. • The temperature decreases since the dilution effect of CO 2 in plume region. • The air entrainment rate is inverse proportional to CO 2 concentration. • A new correlation between CO 2 concentration and temperature has been developed. [ABSTRACT FROM AUTHOR]