EXPERIMENTS ON FLAME SPREAD OF A FUEL DROPLET ARRAY IN A HIGH-PRESSURE AMBIENCE

Flame spread phenomena in a suspended fuel droplet array were experime ntally investigated for n-decane and n-hexadecane in a high-pressure a mbience. Seven droplets of the same size were arranged at equal horizo ntal spacings. Flame spread rates were measured based on OH emission h istories detected by a high-speed video camera with an image intensifi er for droplet diameters of 0.50, 0.75, and 1.0 mm at ambient pressure s from 0.1 to 2.0 MPa. Results show that, as droplet spacing becomes s maller, flame spread rate increases and attains a maximum value at a s pecific spacing. A further decrease in droplet spacing causes the spre ad rate to decrease due to the large latent heat of vaporization. Expe riments were also conducted in a microgravity field to determine ii th ese characteristics of flame spread are affected by natural convection .