Characteristics of nucleate boiling under conditions of pulsed heat release at the heater surface

This paper presents results of the experimental study for the initial stage of the explosive boiling, as well as an attempt to simulate them in order to clarify whether the existing approaches can be extended to the case of the non-stationary heat release. We present data on the onset of nucleate boiling (ONB) and nucleation density for pulsed heat release in the range from 0.56 to 2 MW/m(2). To determine the dynamics of the temperature field under conditions of non-stationary nucleation, a numerical algorithm was implemented, which includes the calculation of the heat fluxes associated with the interphase interaction in the bubble neighborhood. It was shown that for the non-stationary case the previously developed approaches can be applied to numerically predict nucleate boiling characteristics using the Fourier number.