Based on experimental and analytical work conducted previously with R-l13, the results of an analytical study of the vapor bubble dynamics for mercury associated with nucleation and growth are presented here. The simulations show that a growing mercury vapor bubble can be substantially unstable under sufficiently high superheat, as with a superheat level of 100℃, and that surface tension tends to stabilize the process. At a superheat level of 30℃, the growth is marginally stable due to the high surface tension, and quite stable in the very early stages of the growth. For most cases, the wavelength of growing perturbations appear to be relatively large compared to that for water, again due to the large surface tension of mercury. As a result of the high liquid-to-vapor density ratio, the growth rates of mercury vapor bubbles can be quite high, reaching a diameter of 1 m in 1 s, with an initial superheat of 100℃ and pressure of 0.1 atm. The effects of system pressure are also considered here.
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