The subject invention provides a heat sink (20) for cooling electronic devices (24). The heat sink (20) includes an upper chamber (54) and a lower chamber (56) separated by a baffle (52) therebetween. The lower chamber (56) includes a base (38) having a central axis (C) and a plurality of curvilinear fins (36) disposed radially about the central axis (C) of the base (38). The upper chamber (54) includes a lid (46) defining an inlet and an inlet tube (66) interconnecting the upper chamber (54) and the lower chamber (56) for directing a fluid through the upper chamber (54) and impinging the fluid on the base (38) in the lower chamber (56). A sidewall (50) extends between the base (38) and the lid (46) and is disposed about the fins (36). The sidewall (50) includes a peripheral inlet (70) for directing the fluid perpendicular to the central axis (C) and at the fins (36).
