"Cross Flow Fan" fan selection is a more complex process, technically demanding. Fan selection methods are many, such as by logarithmic curve selection, dimensionless characteristic curve selection, etc, as well as a professional cooling fan selection software can also help us selection. Whichever method you choose at the time of the cooling fan selection, we have to grasp these basic principles. Cooling fan manufacturer in terms of new product development performance, to reflect the strength of its technology, consideration should also be included in the selection.