System codes usually simplify physics to a one-dimensional description limiting their capabilities when intrinsically three-dimensional phenomena are of importance, such as in case of pool type thermal-hydraulic systems, where large scale three-dimensional flow pattern exists. The RELAP5 system code modelling of the pool-type LBE-cooled CIRCE facility has been supported by the analysis performed with the two-dimensional SIMMER-III code and qualified by the post-test analysis of the CIRCE DHR experiments. Furthermore, a grid-free pool modelling, i.e. reduced order models (ROM), based on the expansion of flow variables in suitable Proper Orthogonal Decomposition (POD) modes is proposed by KIT to overcome the limits shown by thermal-hydraulic system codes in the simulation of pool-type systems. The POD-modes are computed from representative transient CFD data of the system that has to be modelled. The process of deriving a ROM can be semi-automated.
|Titolo:||Implementation and qualification of pool models in system codes|
|Data di pubblicazione:||6-mar-2015|
|Appare nelle tipologie:||5.2 Documento in Garanzia della Qualità|