Experimental study of unpremixed natural gas flames diluted with CO2 and subject to transversal air flow

This research describes the experimental study of the geometry and thermal radiation of diffusive turbulent flames of natural gas diluted with carbon dioxide subjected to transversal air flow. A dimensionless quantity that relates two forces (fuel jet movement amount and air transverse flow jet amount) is defined as momentum ratio (R). This dimensionless number is used in the models proposed here to compare the experimental results obtained with the literature. In the survey, momentum ratio values ranged from 5003 = R = 873, 67 . It was initially observed that the length of the flame increases with the increase of the fuel flow, while the addition of carbon dioxide in the mixture and the cross flow of air, resulted in an increase in the height of the flame lift and, consequently, a reduction in the slope of the flame length. It was also found that the addition of carbon dioxide caused a reduction in the radiant fraction. The algebraic models proposed for flame length prediction showed accuracy resulting in AARE values in the range of 0.0777-28%.