The temperature contours in Fig. 5 show the flame, which is associated with temperatures beyond 2000 K,
is held on top of both the inner and outer ring of burner holes.
The hot gases are observed to flow out of the top boundary and entrain some cold air from the surroundings. The figure shows that the temperature of these hot burnt gases which are escaping into the atmosphere is between 950 and 1170 K.
It is observed that the heat transfer potential of these gases is not being utilized. Thus,a mechanism which will enhance the heat transfer either by efficiently circulating gas around vessel or by increasing time of contact of hot gases and vessel or increasing temperature gradient between the flue gases and vessel will improve the system thermal efficiency