Convective Heat Transfer Characteristics within a Shipping Container Transporting a Micro-HTGR

Abstract

Current research on generation IV nuclear reactors is furthering the development of micro-reactors as a viable technology that will help provide independent power for communities that are unable to connect to the grid. To accomplish these goals, micro-reactors must be easily transportable, resulting in designs that are meant to fit within a standard shipping container. The high temperature gas reactor (HTGR) is one concept being redesigned as a micro-reactor. Understanding how heat removal phenomena changes as a consequence of the micro-HTGRs' smaller size and horizontal orientation in comparison to a traditional HTGR is crucial to the development of passive safety. A complete understanding has yet to be reached on how reactor vessel surface heat removal characteristics change when confined in a shipping container instead of being cooled in a reactor cavity as in the case of well investigated HTGR designs. A numerical study was validated to demonstrate ANSYS' ability to model natural circulation within a confined space. Using that same model, the study was used to show the Nusselt number variation around the circumference of the reactor vessel when placed in the shipping container under forced or natural convection of the container air.