Effect of normal vibrations of a flat horizontal heater on the second boiling crisis

The effect of normal vibrations of a flat horizontal heater on the second boiling crisis is considered within the framework of the hydrodynamic theory of boiling crises. The critical heat flux is estimated by characteristics of growth of the most dangerous disturbances destroying the liquid-vapor interface. As the vibration intensity increases, the interface can be destroyed either owing to the Rayleigh-Taylor instability or by virtue of parametrically excited disturbances with wavelengths corresponding to resonance zones. In the domain of parameters where the parametric instability in the first resonance zone is the most dangerous factor, it is possible to significantly reduce the critical heat flux, as compared with the value corresponding to the case with no vibrations. With a further increase in vibration intensity, the critical heat flux increases as a whole. The nonmonotonic character of the critical heat flux as a function of vibration intensity allows an effective control of the critical heat flux whose value can be made higher or lower than the value in the case without vibrations. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 4, pp. 88–97, July–August, 2006.