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The thermal-hydraulic behavior of pressurized water reactors (PWRs) during operational transients and accidental conditions are complex and require comprehensive investigations such as:

  • Study of overall system responses and system interactions
  • Demonstration of safety margins and evaluation of PWR operating procedures for design and beyond-design-basis events.

For some accidents / transients calculation codes cannot replicate the thermal-hydraulic behavior sufficiently and need the support of tests.


In our PKL large-scale test facility we can conduct experiments on the thermal-hydraulic behavior of PWRs during operational transients in order to contribute to solve PWR safety issues.

The PKL facility is extensively instrumented, (over 1,800 measuring points) permitting a detailed depiction of the phenomena addressed by the tests. The facility is particularly suited for detailed analyses and interpretation of complex phenomena difficult to assess with thermal-hydraulic system codes.

Your Benefits

  • Worldwide unique 4-loop experimental test facility for comprehensive test results
  • Transient and accident analyses, procedure validation and separate effect tests contribute to solving PWR safety issues



International cooperation within OECD:

  • Large break / small break loss-of-coolant accident
  • Steam generator tube rupture
  • Main steam line breaks
  • Station blackout, loss-of-feedwater transients, bleed-and-feed procedures
  • Systematic studies, e.g. single- / two-phase natural circulation, reflux condenser with / without non-condensable gases

Interested in Pressurized Water Reactor Integral System Test Facility – PKL?