CX-020903: Experiments and Computations to Address the Safety Case of Heat Pipe Failures in Special Purpose Reactors – University of Michigan

The University of Michigan (UM), in collaboration with Idaho National Laboratory (INL), proposes to study the thermo-mechanical stresses on the core structure of a heat pipe micro-reactor following failure of multiple heat pipes. This project explores the application of heat pipe technology to very small modular reactors (vSMRs). Liquid metal (typically sodium [Na], potassium [K], or NaK) heat pipes can operate at very high temperatures and are fully passive heat removal devices. The tasks associated with this project are: 1) Scaling study and pre-test simulations for the design of the experimental facility – using INL software; 2) Construction of the experimental facility – at UM; 3) Definition and execution of experimental campaign – conduct separate effects tests (sonic, vapor pressure, entrainment and boiling limits) to validate and adjust the software models; 4) Validation (and further improvement) of the code suite; and 5) Development of a set of recommendations for heat pip micro-reactors safety case. Experimental equipment will be constructed at UM and existing laboratory facilities will be used.