User:Milton Beychok/Sandbox

Fan laws

The basic fan laws governing the effect of fan wheel rotational speed (RPM) changes on volume (CFM), discharge static pressure (SP) and the drive motor operating horsepower (BHP) are:

${\frac {CFM_{2}}{CFM_{1}}}={\bigg (}{\frac {RPM_{2}}{RPM_{1}}}{\bigg )}$

     ${\frac {SP_{\,2}}{SP_{\,1}}}={\bigg (}{\frac {RPM_{2}}{RPM_{1}}}{\bigg )}^{2}$

${\frac {BHP_{\,2}}{BHP_{\,1}}}={\bigg (}{\frac {RPM_{2}}{RPM_{1}}}{\bigg )}^{3}$