Explosive boiling of liquids on film heaters under the action of pulsed heat fluxes q = 10 8 -10 9 W/m 2 is considered. A technique of stroboscopic visualization of boiling stages with a time resolution of 100 nsec is used. Numerous scenarios of evolution of explosive boiling are demonstrated. Conditions of the thermal effect (magnitude of the heat flux, duration and repetition frequency of heat pulses) are found, which ensure single and repeated boiling, intermittent boiling, and boiling with formation of complicated multi-bubble structures. It is noted that homogeneous nucleation is a dominating mechanism of incipience of examined liquids for q > 10 8 W/m 2 .

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Dynamics of formation, growth, and collapse of a vapor cavity during explosive boiling of liquids on film heaters under the action of pulsed heat fluxes q = 10 8 -10 9 W/m 2 is studied theoretically and experimentally. The description of the vapor-cavity formation process is based on the concept of a homogeneous mechanism of nucleation taking into account the influence of already formed and growing bubbles. Evolution of vapor structures is numerically simulated by solving the equations of dynamics of a compressible liquid with allowance for heat transfer, evaporation, and condensation. A comparison of experimental and numerical data shows that the model proposed offers an adequate description of the main features of explosive boiling of liquids on film heaters, including the effect of conditions of the thermal action and liquid properties on the duration of cavity evolution and on the cavity size.

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