This　paper　presents　an　experimental　investigation　on　the　metal　foam　for　controlling　a　centrifugal　fan　noise.　Nine　samples　of　metal　foam　with　different　types　of　cells,　i.e.,　open,　semi-open　and　close,　are　employed　to　compare　their　effects　on　the　aerodynamic　performance　and　noise　level　of　the　centrifugal　fan.　Experimental　data　confirms　that　the　open　cell　metal　foam　is　the　most　effective　to　control　the　fan　noise　because　it　not　only　significantly　suppresses　the　tonal　noise　but　also　attenuates　the　broadband　noise.　Moreover,　the　geometrical　parameters　of　the　open　cell　metal　foam,　i.e.,　pores　per　inch　and　porosity,　are　studied　to　investigate　their　effects　on　the　aerodynamic　performance　and　noise　level　of　the　centrifugal　fan.　(c)　2015　Elsevier　Ltd.　All　rights　reserved.