Instability in two-phase flows of steam

F. Bakhtar, S. R. Otto, Mohd Zamri Yusoff, J. M. Sarkies

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In two-phase flows of steam, when the velocity is between the equilibrium and frozen speeds of sound, the system is fundamentally unstable. Because any disturbance of the system, e.g. imposition of a small supercooling on the fluid, will cause condensation, the resulting heat release will accelerate the flow and increase the supercooling and thus move the system further from thermodynamic equilibrium. But in high-speed flows of a two-phase mixture, dynamic changes affect the thermodynamic equilibrium within the fluid, leading to phase change, and the heat release resulting from condensation disturbs the flow further and can also cause the disturbances to be amplified at other Mach numbers. To investigate the existence of instabilities in such flows, the behaviour of small perturbations of the system has been examined using stability theory. It is found that, although the amplification rate is highest between the equilibrium and frozen speeds of sound, such flows are temporally unstable at all Mach numbers.

Original languageEnglish
Pages (from-to)537-553
Number of pages17
JournalProceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume464
Issue number2091
DOIs
Publication statusPublished - 08 Mar 2008

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Supercooling
Acoustic wave velocity
two phase flow
Two-phase Flow
Two phase flow
steam
Mach number
Condensation
Steam
Thermodynamics
Fluids
Thermodynamic Equilibrium
Amplification
supercooling
thermodynamic equilibrium
disturbances
condensation
Heat
Disturbance
Unstable

All Science Journal Classification (ASJC) codes

  • Mathematics(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

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Instability in two-phase flows of steam. / Bakhtar, F.; Otto, S. R.; Yusoff, Mohd Zamri; Sarkies, J. M.

In: Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 464, No. 2091, 08.03.2008, p. 537-553.

Research output: Contribution to journalArticle

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