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An evaporation of kerosene and water was investigated based on convective heat transfer in the experimental setup simulating a typical volume of the fuel tank of the launch vehicle. Basic criteria of similarity used in choosing the design parameters of the setup, parameters of the coolant and model liquids, were numbers of Reynolds, Prandtl, Biot, and Nusselt. The used coolants were gases, including air and nitrogen; in addition, at the stage of preliminary experiments, products of combustion of hydroxyl-terminated polybutadiene (HTPB) were considered. Boundary conditions were taken for the liquid located on the plate in the form of “drop” and at its uniform film spread in the experimental model setup. On the basis of experimental investigations, the temperature values were obtained for the system “gas-liquid-wall”, and areas of mass transfer surface and heat transfer coefficients of “gas-liquid” and “gas-plate” were determined for coolants (air and nitrogen) and for liquids (water and kerosene). The comparative analysis of the obtained results and the known data was carried out. Proposals for experiments using coolants based on HTPB combustion products have been formulated

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On the basis of the first law of thermodynamics, a thermodynamic physical and mathematical model of the process of evaporation and freezing in a partially filled closed volume of a liquid under acoustic exposure (AE) and pressure reduction has been developed. The acoustic effect on the liquid is taken as a component on the heating of the liquid in the closed volume. The experimental studies performed under AE (amplitude 2.0 μm, frequency 25 kHz), initial temperature, and mass of the liquid 300.85 K, 7 g, respectively, the pressure decreases from 101 to 0.5 kPa showed a close coincidence of the actual and calculated moments of freezing start liquid surfaces, as well as close calculated and experimental values of liquid temperatures during the experiment.