Customer Projects

Fraunhofer-Institut für Algorithmen und Wissenschaftliches Rechnen SCAI

Condensation Pool Experiments at LUT Supporting CFD and Structural Analysis Tool Development

Markku Puustinen, Antti Räsänen, Jani Laine, Heikki Purhonen - LUT Energy, Faculty of Technology, Lappeenranta University of Technology

Timo Pättikangas, Antti Timperi - VTT Technical Research Centre of Finland

at 20th International Conference on Structural Mechanics in Reactor Technology (SMiRT 20)

Nuclear power plant safety has been experimentally investigated at Lappeenranta University of Technology (LUT). In addition to the thermal hydraulic studies it has been beneficial to add instrumentation for structural measurements into the test facilities as well. This way, running tests aiming to solve thermal hydraulic problems, can also serve other purposes such as producing data for developing tools for Computational Fluid Dynamics (CFD) and structural analysis.

At VTT, coupling of commercial CFD and structural analysis codes has been done for analyzing Fluid- Structure Interaction (FSI). One-way coupled calculations, in which only the pressure is transferred to the structure, were first carried out with an in-house code based on the MpCCI library. Later commercial middleware ES-FSI and MpCCI have been used for analyzing also two-way FSI, in which the deformations of the structure are accounted for in the flow solution (Räty and Puska, 2006).


The main goal of the work at LUT has been to gather data of structural loads from thermal hydraulic tests. Coupled CFD and structural analysis codes can then be validated against measured structural loads related to thermal hydraulic phenomena such as rapid condensation, gas bubble formation and detachment.