Thermal and concentration fields of burner-attached jet flames in cross flow

Abstract

The thermal and concentration structures of the burner-attached jet flames in cross flow were experimentally studied. Due to the complex interaction among the cross air flow, issuing fuel jet, and burner tube, the flame behavior in the area around the burner tip was characterized by several modes for different ranges of jet-to-wind momentum flux ratio. The temperature and concentration profiles of the flames of the different characteristics modes presented drastic variations. At low jet-to-wind momentum flux ratios, the downwash flame anchored behind the burner tube. The temperature profiles of the downwash flame near the burner tip were characterized by two side peaks and a center deep. At mid jet-to-wind momentum flux ratios, a center hump presented in the temperature profile. At high jet-to-wind momentum flux ratios, the downwash flame disappeared. The flame existed in the lee side of the issuing fuel jet body and was characterized by two side peaks and a center deep, although the deep was shallow. The temperature variation near the burner tip occurring prior to the blowoff of the flame was discussed. The concentration profiles of CO, CO 2, and O 2 illustrated the effects of mixing in different characteristics flame modes. The complex characteristics of the temperature and concentration fields suggested that the conventionally used diffusion flame model for the liftable jet flame in cross flow was not adequate for the burner-attached jet flame in cross flow.