抄録
Data center has been built with spread of cloud computing. Further, electric power consumption of it is growing rapidly. High power cooling fans are used for servers in the data center and there is a strong demand to increase power of it because of increase of quantity of heat from the servers. Contra-rotating rotors have been adopted for some of the high power cooling fans.Contra-rotating axial fan is smaller than single axial fan under the same rotational speed, and is higher efficiency compared with single small-sized axial fan. It is important to clarify complicated internal flow condition and influence of a geometric shape of the cooling fans on performance and internal flow condition to achieve the high performance cooling fans. Numerical analysis of a cooling fan with 40mm square was conducted and influences of inlet of casing,tip clearance,maximum turning angle position and shape between front and rear rotors on performance were investigated experimentally in this research.
