The condensing flow of supercooled steam in a convergent–divergent nozzle is treated theoretically. It is shown that when condensation occurs in the supersonic section of the flow, if the heat released by condensation exceeds the quantity which reduces the flow Mach number to unity, the flow becomes unstable.
As a result of the investigation, critical instability boundaries have been plotted as a locus on the Mollier diagram which divide the initial entry conditions to a nozzle into stable and unstable zones.
The findings have been verified experimentally on a converging–diverging nozzle and good agreement obtained between theoretical and experimental results.
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