The present paper deals with the preliminary analytical study of the PKL experiment F4.1 performed using the TRACE code (version 5.0). The test F4.1 executed in PKL-III facility investigates both, the boron dilution occurrence and the heat transfer from primary to secondary side under natural circulation conditions (single and two phase flow) and reflux condensation. The boron dilution events in condition of reduced mass inventory, namely during a SB-LOCA scenarios, are considered. The relevance of those transient is connected with the possibility that unborated coolant enters in the core, causing re-criticality or, worse, power excursions. The numerical investigation is performed by developing a complete TRACE input model of the PKL integral test facility, including secondary as well as primary system. The aim of this work is the assessment of the TRACE code against the boron transport and the heat transfer mechanism in the different flow regimes that take place during the experiment. The accuracy of the calculation is evaluated by qualitative and quantitative analysis. The quantification of the accuracy is performed using the Fast Fourier Transform Base Method (FFTBM) developed at University of Pisa. The tool provides an integral representation of the accuracy quantification in the frequency domain.
Numerical Investigation of Natural Circulation during a Small Break LOCA Scenarios in a PWR-System Using the TRACE v5.0 Code
D'AURIA, FRANCESCO SAVERIO
2010-01-01
Abstract
The present paper deals with the preliminary analytical study of the PKL experiment F4.1 performed using the TRACE code (version 5.0). The test F4.1 executed in PKL-III facility investigates both, the boron dilution occurrence and the heat transfer from primary to secondary side under natural circulation conditions (single and two phase flow) and reflux condensation. The boron dilution events in condition of reduced mass inventory, namely during a SB-LOCA scenarios, are considered. The relevance of those transient is connected with the possibility that unborated coolant enters in the core, causing re-criticality or, worse, power excursions. The numerical investigation is performed by developing a complete TRACE input model of the PKL integral test facility, including secondary as well as primary system. The aim of this work is the assessment of the TRACE code against the boron transport and the heat transfer mechanism in the different flow regimes that take place during the experiment. The accuracy of the calculation is evaluated by qualitative and quantitative analysis. The quantification of the accuracy is performed using the Fast Fourier Transform Base Method (FFTBM) developed at University of Pisa. The tool provides an integral representation of the accuracy quantification in the frequency domain.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
