The　advanced　accumulator　is　used　in　the　nuclear　power　station　and　plays　an　important　role　in　a　loss-of-coolant　accident　(LOCA).　In　this　paper,　a　prototype　model　of　the　advanced　accumulator　based　on　the　existing　ones　abroad　was　proposed　and　studied　by　using　numerical　simulation.　The　results　show　that　for　the　proposed　model　the　required　variation　pattern　of　the　water　flow　rate　with　time　can　be　obtained　by　using　multi-scale　mesh.