Corrected flow

Corrected Flow is the mass flow that would pass through a device (e.g. compressor, bypass duct, etc.) if the inlet pressure and temperature corresponded to ambient conditions at Sea Level, on a Standard Day (e.g. 14.696 lbf/in², 518.7R).

Corrected Flow, $w{\sqrt {\theta }}/{\delta }$ , can be calculated as follows, assuming Imperial Units:

$w{\sqrt {\theta }}/{\delta }=w{\sqrt {T/518.7}}/(P/14.696)$

Corrected Flow is often given the symbol $wc$ or $wr$ (for referred flow).

So-called Non-Dimensional Flow, $w{\sqrt {T}}/{P}$ , is proportional to Corrected Flow:

$w{\sqrt {T}}/{P}=w{\sqrt {\theta }}/{\delta }*{\sqrt {518.7}}/{14.696}$

The equivalent equations for Preferred SI Units are: (101.325kPa, 288.15K)

$w{\sqrt {\theta }}/{\delta }=w{\sqrt {T/288.15}}/(P/101.325)$

$w{\sqrt {T}}/{P}=w{\sqrt {\theta }}/{\delta }*{\sqrt {288.15}}/{101.325}$

Nomenclature:

$P$ Stagnation (or Total) Pressure
$T$ Stagnation (or Total) Temperature
$w$ Real Mass Flow
${\delta }$ Referred Pressure
${\theta }$ Referred Temperature

In relative form, Corrected Flow, Referred Flow and Non-Dimensional Flow are all measures of axial Mach number.

Side note: If the mass flow can be considered an energy source such as fuel flow, the corrected flow is calculated as follows:

$w/(\delta *{\sqrt {\theta }})$

See also