ICONE23-1011 SPECIFIC FEATURES OF STRONGLY SUPERHEATED STEAM CONDENSATION ON THE SURFACE OF HIGHLY SUBCOOLED WATER JETS APPLIED TO NEW DESIGN OF HIGH PRESSURE REHEATER

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In the present work it is shown that physically accurate structure of dependences for heat transfer during condensation of vapor on the surface of subcooled jet can be obtained by considering the effect of surface tension at the phase boundary and the unsteady nature of the proceeding thermal hydraulic processes. Currently absent not only the quantity theory of heat transfer in film boiling strongly subcooled liquid, but also convincing qualitative explanation of the high intensity of heat transfer between the superheated solid surface and the subcooled liquid under conditions when direct contact between surface and liquid is impossible. For the case of superheated steam condensation on the surface of the jet strongly subcooled liquid heat transfer are considered similarly to the processes of heat transfer at inverted annular flow and quenching . It is known that the experimental heat transfer coefficients for subcooled water film boiling for 1-2 orders of magnitude more than the observed at the film boiling of saturated liquid. Until now, a reasonable explanation for such strong effect was not found. It is shown that taking into account the wave nature of the process possible to obtain quantitative values of heat transfer coefficients, more or less agreed with the experimental data.