TEST AND CALCULATION ON THE EMERGENCY CON DENSER OF THE SWR-1000

Siemens AG is developing the new innovative boiling water reactor conc ept SWR-1000. New features are the passive safety systems (e.g. emerge ncy condensers, building condensers, passive pressure pulse transmitte rs). For the experimental investigation of the emergency condenser eff ectiveness, the Noko test facility has been constructed at the Forschu ngszentrum Julich in cooperation with Siemens. The facility has an ope rating pressure of 10 MPa and a maximum power of 4 MW for steam produc tion. The condenser bundle consists of 8 tubes and is fabricated with the geometry and material as planned for the SWR. In more than 200 exp eriments, the emergency condenser capacity was tested as a function of pressure, water level and concentration of non-condensables in the pr essure vessel as well as pressure, water level and temperature in the condenser. Posttest calculations of Noko experiments were performed wi th an improved version of Athlet. To calculate the heat transfer coeff icients during condensation in horizontal tubes the module Konwar has been developed and implemented in Athlet. Konwar is based on the flow regime map of Tandon and includes several semi-empirical correlations for the determination of the heat transfer coefficients. The presented comparison between calculations and experiments shows a good agreemen t.