Combustion kinetics of pure hydrocarbons (n-Octadecane, n-Docosane) is studied experimentally by videomicroscopy. Burning droplets histories are obtained and analyzed. It is shown that droplet vaporization and combustion is obeyed d2-law. Burning rate coefficients are determined for different initial sizes of droplets.

Characteristics of ignition and combustion of two n-Octadecane droplets placed vertically are studied by videomicroscopy. Upper droplet burning histories are obtained for different droplet spacing, burning rate constants are determined. To clarify flame spread along fuel droplet array ignition delay is measured at different droplet spacing.

The alkanes melting (n-Octadecane, n-Docosane) is studied experimentally. The droplets size and shape histories are analyzed and compared with the characteristics of n-alkanes phase transition solid-liquid. It is found that the droplet equivalent diameter increases significantly due to melting and thermal expansion. At the same time its shape evolves continuously: initially elongated droplet becomes almost spherical then elongates again. The droplet aspect ratio non-monotonic change correlates with surface tension temperature dependence.