Initiation of organic coal–water fuel droplet burning in a vortex combustion chamber

Using a test bench the main part of which is a vortex combustion chamber, characteristics describing the initiation of burning of solitary droplets of a typical organic coal–water fuel (OCWF) are established. The oxidizer temperature varied in the range of 600–850 K. The linear motion velocity of the oxidizer in the vortex chamber was about 3 m/s. The configuration of the chamber and parameters of the air flow provided a stable regime of floating for droplets with a size (radius) of about 0.5 mm. The analysis results show that the intensity of initiation of OCWF combustion under conditions of processes occurring in boiler furnaces is significantly (by a factor of 2–4) higher than for droplets that are immovably fixed or freely float in the heated air flow.