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[References: 37 tit.]

The paper presents experimental research findings for the convection velocities in the gas and liquid phases during micro-explosive fragmentation of droplets heated on a solid surface. The experiments were conducted with two types of bi-component droplets: emulsified and unmixed ones. A scheme with an induction heater in the temperature range of 75–550 °C was used. The convection velocities were recorded in droplets during heating, rapid evaporation, partial fragmentation in the puffing regime and full fragmentation in the micro-explosion regime. Typical shapes and dimensions of the origins of vortex formation were distinguished. The velocities of vapor outflow from the surface of the droplet and secondary fragments as a result of droplet breakup were established. Their variation ranges were determined. The effect of the surface temperature, droplet dimensions, component composition of liquid and type of droplets on these velocities was identified. The research findings were compared with the previous data obtained in experiments with a droplet fixed on a holder in a hot air flow. We showed threshold convection velocities in droplets sufficient for their breakup during puffing and micro-explosion regimes. General approximations were derived for the convection velocities in the droplets under study versus the substrate temperature.