I am trying to determine the approximate CFM of several axial flow fans being used in agricultural storage in the developing world. The only information the storers have is the power, RPM, and diameter of their fans.
I would like to estimate the CFM at various levels of Static Pressure, and within a range of likely blade pitches.
Is there a way to to do this? I've looked at the fan laws, but it seems like these are meant to calculate changes in variables, not the absolute values of the variables themselves.