# 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:

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