The immersed body supermeshing method for modelling reactor physics problems with complex internal structures - Buchan, AG; Farrell, PE; Gorman, GJ; Goddard, AJH; Eaton, MD; Nygaard, ET; Angelo, PL; Smedley-Stevenson, RP; Merton, SR; Smith, PN (ANNALS OF NUCLEAR ENERGY, 2014)