Two-dimensional combustion flame front and temperature profiles of ultra low-calorific gases in porous combustor are investigated numerically.The characteristics of the flame front,high temperature profiles under certain operating parameters,and the flame propagation process are examined.The effects of operating parameters,such as equivalence ratio,superficial velocity of gas and the wall heat loss,on the flame front and high-temperature zone are analyzed.The results show that the shape of the flame front is gradually changed in the propagation process of the flame.Accordingly,this process results in the variation of the high temperature zone.As the equivalence ratio increases,the inclination of the flame front near the wall decreases gradually,while the combustion flame propagates upstream gradually.The shape of the flame front gradually changes from the trapezoid to the straight-line distribution with downward inclination on both sides.The effect of gas velocity on the shape and position of flame front is contrary to that of the equivalence ratio.On the other hand,the wall-heat loss can lead to the inclination of the flame front near the combustor wall,while the effect on the position of flame is less.
