Preliminary coupling of OpenMC and Nek5000 within the moose framework

This paper presents a Monte Carlo-computational fluid dynamics coupling of OpenMC and Nek5000 within the Moose framework. This coupling specifically aims to address and overcome challenges encountered in earlier coupling works such as file-based communication and overly restrictive one-to-one mesh mappings between the codes. In addition, coupling within the Moose framework offers the possibility of relatively easy coupling to any other Moose application. The advantages of the coupling framework are illustrated with a simple pin cell example; to demonstrate the ease of coupling to other Moose applications, a lightweight surrogate for Bison, called Buffalo, is used to solve for the nuclear fuel physics. (author)