"Micro Cooling Fan" dimensionless performance parameters, but also the number of similar characteristics, and therefore all similar fan, regardless of the size of the size, height and size of the rotational speed of the fluid density, in the corresponding operating point K, they are dimensionless parameter equal. For a series of similar fans, each "Micro Cooling Fan" has its own fan performance curve. When using the dimensionless coefficients indicate, this series all the corresponding conditions for a dimensionless point coincides operating point, the series all corresponding performance curve will coincide for a non-dimensional performance curve. Thus, for a similar series of fan performance "Micro Cooling Fan", available in a set of non-dimensional performance curves.