Heat Pipe Temperature Oscillation Effects on Solid-State Reactor Operation

Abstract The alkali metal heat pipes are the critical transfer elements in pipe cooled reactors. However, there instabilities such as geyser boiling, resulting temperature oscillation and even threatening reactor safety. This work developed a coupled neutronic thermal-mechanical analysis method to analyze effects of boiling oscillations on parameters, e.g., stress, during operation. megawatt MegaPower was chosen an application case. simulations show that leads same frequency stress solid-state core. Besides, amplitudes significantly reduced by shortening period. Reducing period from 60 s 15 amplitude fuel pellet center 22℃ 5℃. Furthermore, core may lead material fatigue or failure for long operation, which is highly undesired. can provide valuable data references safety design