Characterization of bluff-body stabilized LPG jet diffusion flame with N2 dilution

Measurements of several parameters like flame length, soot free length fraction (SFLF), radiant fraction, gas temperature and emission levels are performed in coaxial LPG jet diffusion flame to provide an insight into the effect of lip thickness and inert addition on flame characteristics. The present measurements reveal that the visible flame length is found to be reduced with increase in lip thickness. In contrast, the flame length for all lip thicknesses gets enhanced by inert addition to the fuel stream, which can be attributed to the reduced diffusivity of the mixture gases. The SFLF is seen to be enhanced with N2 addition due to decrease in the fuel concentration and flame temperature. However, the SFLF is reduced with increasing lip thickness of the bluff-body which is caused due to the reduction in induction period of soot formation. For all lip thickness, the NOx emission level is observed to be attenuated with inert (N2) addition, which can be ascribed to reduction in residence time of gas mixture. Besides this, NOx emission level is enhanced with increasing lip thickness. The emission index of CO is found to be increased with nitrogen addition; in contrast, the EICO2 is seen to be reduced, for all lip thickness. This can be attributed to attrition in residence time with inert addition that tends to inhibit the conversion of CO to CO2. Moreover, EICO is also observed to be attenuated while EICO2 gets enhanced, with increasing lip thickness which might be due to the increased residence time of mixture gases.