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A comparison of metastable flows of condensation in Laval nozzles and vaporization in capillary tubes

Part of the Acta Mechanica book series (ACTA MECH.SUPP., volume 4)

Summary

One-dimensional metastable flows with condensation of moist air in Laval nozzles and vaporization of Refrigerant-12 in capillary tubes are considered. The locations of the inception of condensation in Laval nozzles and vaporization in capillary tubes can be predicted. A steady “condensation” shock occurs in the supersonic part of a Laval nozzle. The effect of moisture condensation on the flow properties is in the downstream of the shock. For an unsteady and periodic condensation process, the effect of moisture condensation on the flow properties may be either in the downstream of the shock, or in both directions, downstream and upstream of the shock, dependent on the location of the shock. For vaporization of refrigerant in capillary tubes, the back pressure has an effect on the pressure distribution along the whole capillary tube, when the flow is at a non-critical flow condition. For a critical flow condition, the back pressure has no effect on the pressure distribution upstream of the location of the inception of vaporization. However, it does have an effect on the pressure distribution downstream of the location of the inception of vaporization. It shows that in the two-phase flow with vaporization, the critical flow rate is not controlled by the sonic speed at the exit of the capillary tube.

Keywords

Pressure Distribution Capillary Tube Back Pressure Heat Addition Critical Flow 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • S. Lin
    • 1
  1. 1.Department of Mechanical EngineeringConcordia UniversityMontrealCanada

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