Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5

Lukasz Sokolowski, Tomasz Kozlowski

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Two-phase critical non-flashing flow might occur, e.g. when a system filled with water and non- condensable gas as air or nitrogen, is emergency released. The common practice in Swedish industry is to employ one-dimensional system codes such as RELAP5 to calculate this type of flow. Such codes have in-build two-phase critical flow models which are intended for flashing steam-water mixture. However, non-flashing flows are different in its nature than flashing flows and because of this the default models might provide non-physical results. This paper aims to validate these models against experimental data and provide recommendations on how to predict non-flashing flows with satisfactory accuracy. Validation was performed against experimental data of [1] - [3] with water stagnation pressure conditions varying from 0.1 to 1.56 MPa, temperature subcooling in the range of 84.7 - 195.6 °C, maximum air mass flux of 383.2 kg/(m2 sec) and discharge section geometry arranged as an open pipe outlet, converging-diverging nozzle and converging nozzle.

Original languageEnglish (US)
Title of host publicationInternational Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015
PublisherAmerican Nuclear Society
Pages2117-2130
Number of pages14
ISBN (Electronic)9781510811843
StatePublished - Jan 1 2015
Event16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2015 - Chicago, United States
Duration: Aug 30 2015Sep 4 2015

Publication series

NameInternational Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015
Volume3

Other

Other16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2015
CountryUnited States
CityChicago
Period8/30/159/4/15

Fingerprint

recommendations
Nozzles
Water
nozzles
Air
noncondensable gases
critical flow
stagnation pressure
Steam
Mass transfer
Pipe
water pressure
air masses
Nitrogen
emergencies
outlets
Geometry
steam
water
Gases

Keywords

  • Non-flashing mixtures
  • Nuclear safety analysis
  • Two-phase critical flow

ASJC Scopus subject areas

  • Instrumentation
  • Nuclear Energy and Engineering

Cite this

Sokolowski, L., & Kozlowski, T. (2015). Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5. In International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015 (pp. 2117-2130). (International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015; Vol. 3). American Nuclear Society.

Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5. / Sokolowski, Lukasz; Kozlowski, Tomasz.

International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015. American Nuclear Society, 2015. p. 2117-2130 (International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015; Vol. 3).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Sokolowski, L & Kozlowski, T 2015, Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5. in International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015. International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015, vol. 3, American Nuclear Society, pp. 2117-2130, 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2015, Chicago, United States, 8/30/15.
Sokolowski L, Kozlowski T. Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5. In International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015. American Nuclear Society. 2015. p. 2117-2130. (International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015).
Sokolowski, Lukasz ; Kozlowski, Tomasz. / Recommendations on two-phase critical non-flashing flows calculations in one-dimensional system code RELAP5. International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015. American Nuclear Society, 2015. pp. 2117-2130 (International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015).
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