407123 Datasheet, PDF (7/8 Pages) Extech Instruments Corporation. – Hot Wire Thermo-Anemometer

Useful Equations and Conversions
Area equations
The volume of air flowing through a duct or vent can be determined by taking the area of
the duct in square units (i.e. square feet) and multiplying this value by the measured
linear velocity (i.e., feet per minute). This gives: ft/min x ft² = ft³/min (CFM)
H
R
W
A=WxH
A = pi x R²
Cubic equations
CFM (ft³/min) = Air Velocity (ft/min) x Area (ft²)
CMM (m³/min) = Air Velocity (m/sec) x Area (m²) x 60
Units Conversion Table
1 m/s
1 ft/min
1 knot
1 km/hr
1 MPH
m/s
1
0.00508
0.5144
0.2778
0.4464
ft/min
196.87
1
101.27
54.69
87.89
knots
1.944
0.00987
1
0.54
0.8679
km/hr
3.6
0.01829
1.8519
1
1.6071
MPH
2.24
0.01138
1.1523
0.6222
1
7
407123 V6.2 3/08