TY - JOUR
TI - Experimental investigation on lift-off, blowout and drop-back in partially premixed LPG open flames in tubular burner
AU - Abdul Gani Zeenathul Farida
JN - Thermal Science
PY - 2022
VL - 26
IS - 6
SP - 4607
EP - 4615
PT - Article
AB - The higher pollutant level in non premixed combustion and safety issues  pertaining to premixed combustion can be counteracted by partially-premixed  mode of combustion. The partially premixed flames (PPF) exhibit the benefits  of both premixed and non premixed flames. PPF enhances complete combustion  leading to reduced soot formation and hence lower emission. However, the  equivalence ratio plays an important role in the stability of such flames.  This paper reports the experimental investigation on the flame  characteristics and stability of partially premixed LPG-air flames in  tubular burner. The stability curve obtained for the base case without any  secondary flow shows that the velocity at lift-off, drop-back and blowout  increases with increasing equivalence ratio. In the presence of secondary  co-flow air, the lift-off and blow off velocity decreases compared to base  case indicating poor stability due to extensive flame stretch leading to  aerodynamic quenching. The experimental results show that the velocity of  flow at lift off, blow out and drop back are higher in the presence of  secondary swirl air than the base case. Co-swirl air increases the stability  due to better mixing at the flame base with increased residence time. Flame  stability deteriorates with co-flow air as co-flow strains the flame  boundary due to flame stretch.