A numerical study is presented on the heat transfer characteristics of two kinds of CPU heat sinks, with one of plain plate fin structure and the other of sub-sectioned plain plate fin structure, under the circumstances of different power input and approaching velocity. 对整体平直翅片与分段开缝平直翅片两种不同结构的CPU散热器,在不同加热功率和不同风速下的散热特性进行了数值模拟。