Phase Change Phenomena of Water under Depressurization State


  • T Watanabe
  • M Nakamura
  • K Tokunaga
  • T Shiigi
  • H Ohta
  • K Shimojima



Latent heat of vaporization of water is very large compared to the latent heat of vaporization of other fluids. Therefore, when evaporation is promoted by decompressing, water lowers the temperature and freezes finally. We froze without heat exchange by exposure to vacuum the water using a vacuum pump. Despite violent boiling occurs, pressure in the vessel was going down. But, finally, at freeze process, the pressure in the vessel was increased. This pressure rise is caused by that amount of evaporation increases temporarily rapidly. The rapid increase in the amount of evaporation is due to the release of latent heat during freezing. This paper was focused on the pressure temperature change and mass change when the phase change of the water is switched to sublimation from the evaporation. This is likely to provide useful information when considering a phase-change model in a special state.


Edwards, A. R. and O'Brien, T. P., 1970, "Studies of Phenomena Connected with the Depressurization of Water Reactors", J.Br. Nucl. Energy Soc., Vol.9, pp.125-135.

Lienhard, J.H., Alamgir, Md. and Trela, M., 1978, "Early Response of Hot Water to Sudden Release from High Pressure", ASME Journal of Heat Transfer, Vol.100, No.3, pp.473-495.

Alamgir, Md., Kan, C.Y. and Lienhard, J.H., 1980, "An Experimental Study of the Rapid Depressurization of Hot Water", Trans. ASME Journal of Heat Transfer, Vol.102, No.3, pp.433-438.

Guler. M., Hannemann, R. J. and Sallet, D. W., 1979, "Unsteady Two-Phase Blowlowdown of a Flashing Liquid from a Finite Reservoir", Two-Phase, Heat & Mass Transf., Vol.2, Hemisphere, pp.781-795.

Alamgir, Md. and Lienhard,J.H., 1981, "Correlation of Pressure Undershoot During Hot-Water Depressurization", ASME Journal of Heat Transfer, Vol.103, pp.52-55.

Watanabe, T., Hanaoka, Y. and Tokura, I., 1995, "Flashing Phenomena of Liquid Nitrogen in a Pressure Vessel", Trans. JSME, (in Japanese), Vol.61, No.585, pp.1849-1854.

Yokoyama, S., Hanaoka, Y., Tokura, I. and Watanabe, T., 1992, "A Study of Liquid Nitrogen Flashing under Rapid Depressurization", Proc. 2nd JSME-KSME Thermal Engng. Conf., Vol.3, pp.321-326.

Watanabe, T., Hanaoka, Y. and Tokura, I., 1998, "Flashing Phenomena of Liquid Nitrogen in a Pressure Vessel: Part 2: Mist formation and Behavior of the Liquid Surface in the Early Depressurization Process", Heat Trans. Japanese Research, Vol.27, No.5, pp.327-335.;2-x

Plunket, T.L. and Scull, T.D., 1994, "Effects of Depressurization of Space Modules on Condensing Heat Exchangers", SAE Transactions Journal of AEROSPACE, Vol.103, Section 1, pp.1689-1696.

Kowalczyk, W., Hartmann, C. and Delgado, A., 2003, "Freezing and thawing at the high hydrostatic pressure conditions – modeling and numerical simulation ", Proc. Appl. Math. Mech., Vol.3, pp.388-389.

Kulisiewicz, L., Kowalczyk, W., Baars, A. and Delgado, A., 2007, "Visualization of pressure-shift freezing and thawing of concentrated aqueous sucrose solutions", Int. Journal of High Pressure Research, Vol.27, No.2, pp.291-297.

Ivashniov, O. E. and Ivashneva, M. N., 2016, "Vapor explosion under hot water depressurization flow", Journal of Fluid Mechanics, Vol.812, pp.65-128.

Polanco, G., Holdo, A. and Munday, G., 2009, "Mass flow determination in flashing openings", Int. Journal of Multiphysics, Vol.3, No.4, pp.401-406.

Haque, E.E.U. and Hampson, P.R., 2014, "Modelling Phase Change in a 3D Thermal Transient Analysis", Int. Journal of Multiphysics, Vol.8, No.1, pp.49-67.

Messahel, R., Cohen, B., Moatamedi, M, Boudlal, A., Souli, M. and Aquelet, N., 2015, "Numerical and experimental investigations of water hammers in nuclear industry", Int. Journal of Multiphysics, Vol.9, No.1, pp.21-36.



How to Cite

Watanabe, T., Nakamura, M. ., Tokunaga, K., Shiigi, T., Ohta, H. and Shimojima, K. (2021) “Phase Change Phenomena of Water under Depressurization State”, The International Journal of Multiphysics, 15(4), pp. 379-388. doi: 10.21152/1750-9548.15.4.379.




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