To　improve　the　cooling　performance　of　a　disc　brake　system,　we　introduce　a　new　concept　of　bidirectional　ventilated　brake　disc　with　an　X-type　lattice　core.　Transient　and　steady-state　thermo-fluidic　behaviors　of　the　new　brake　disc　are　experimentally　characterized　and　compared　with　a　prevalent　radial　vane　brake　disc　under　identical　conditions.　Transient　heating-up　tests　at　a　constant　rotating　speed,　simulating　continuous　downhill　braking,　show　that　both　brake　discs　exhibit　a　similar　temperature　during　initial　period,　whilst　evidently　lower　temperature　can　be　achieved　by　the　new　brake　disc　under　steady-state　conditions.　For　a　given　rotating　speed　in　typical　operating　range　(i.e.,　200-1000　rpm),　steady-state　tests　reveal　that　the　new　brake　disc　provides　1-14%　higher　overall　Nusselt　number　than　the　reference　one.　Although　the　X-type　lattice　core　provides　43%　less　pumping　capacity　than　radial　vanes,　more　complex　flow　mixing　and　1.1　times　more　heat　transfer　area　caused　by　the　lattice　core　are　responsible　for　the　superior　overall　cooling　performance　of　the　new　brake　disc.　In　addition,　the　morphological　anisotropy　of　the　lattice　core　induces　circumferentially　non-uniform　heat　transfer　in　the　disc.　The　most　open　orientation　of　the　lattice　core　provides　substantially　higher　heat　transfer　than　the　most　blocked　orientation.　Mechanisms　of　the　anisotropic　heat　transfer　pattern　are　experimentally　explored.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.