(a) Enhanced images of
the flame receding downstream for 0.3 m/s coflow. The fuel velocity was increased from 36.9 to
41.7 m/s to cause blowout (line 2, Table 1). The entire flame is blue in color. (b) Inverted images of the flame after being reignited at time zero,
with 34.3 m/s fuel velocity and 0.55 m/s coflow (line 4, Table 2). The distance, h, from the fuel nozzle to the lifted flame front is measured for
each.