A SUBCHANNEL COARSENING METHOD FOR Serpent2-SUBCHANFLOW APPLIED TO A FULL-CORE VVER PROBLEMManuel García, Diego Ferraro, Ville Valtavirta, Riku Tuominen, Uwe Imke, Luigi Mercatali, Victor Sanchez-Espinoza and Jaakko LeppänenEPJ Web Conf., 247 (2021) 06018DOI: https://doi.org/10.1051/epjconf/202124706018