Open AccessThermalhydraulic behavior of electrically heated rod during a critical heat flux transient
Author(s) -
Ricardo Carvalho Lima,
Pedro Carajilescov
Publication year - 2000
Publication title -
revista brasileira de ciências mecânicas
Language(s) - English
Resource type - Journals
ISSN - 0100-7386
DOI - 10.1590/s0100-73862000000400010
Subject(s) - overheating (electricity) , mechanics , rod , materials science , coolant , critical heat flux , heat flux , front velocity , nuclear engineering , transient (computer programming) , flux (metallurgy) , front (military) , thermodynamics , heat transfer , meteorology , electrical engineering , physics , engineering , medicine , alternative medicine , pathology , computer science , metallurgy , operating system
In nuclear reactors, the occurrence of critical heat flux leads to fuel rod overheating with clad fusion and radioactive products leakage. To predict the effects of such phenomenon, experiments are performed using electrically heated rods to simulate operational and accidental conditions of nuclear fuel rods. In the present work, it is performed a theoretical analysis of the drying and rewetting front propagation during a critical heat flux experiment, starting with the application of an electrical power step from steady state condition. After the occurrence of critical heat flux, the drying front propagation is predicted. After a few seconds, a power cut is considered and the rewetting front behavior is analytically observed. Studies performed with various values of coolant mass flow rate show that this variable has more influence on the drying front velocity than on the rewetting one