In　this　paper,　Computational　Fluid　Dynamics　(abbr.　as　CFD)　numerical　simulation　method　was　adopted　to　study　the　internal　flow　field　of　experimental　dry　granulating　device　of　blast　furnace　slag,　and　to　research　the　impact　of　equipment　structure　and　wind　speed　on　cooling　effectiveness.　Main　content　included　the　internal　flow　field　uniformity　under　different　blade　type　and　number　of　inlets.　The　results　showed　that　the　internal　flow　field　in　strip-blades　device　was　more　uniform　than　fan-shaped　blades　device.　With　the　increase　of　air　inlets　quantity,　the　internal　flow　field　in　device　became　more　uniform　and　stable,　especially　when　there　were　8　air　inlets　in　the　equipment.　©　2019　Trans　Tech　Publications,　Switzerland.