TSI Incorporated VelociCalc 8345, Руководство по эксплуатации и обслуживанию

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Appendix C
Standard Velocity vs. Actual
Velocity
Since thermal air velocity sensors are sensitive to
changes in air density and air velocity, all thermal
anemometers indicate velocities with reference to a
set of standard conditions. For TSI instruments,
standard conditions are defined as 70° F (21.1° C)
and 14.7 psia (101.4 kPa). Other manufacturers
may use different values.
Standard velocity is the velocity the air would be
moving if the temperature and pressure were at
standard conditions. It is usually the most useful
measure of airflow because it defines the heat-
carrying capacity of the air.
Actual velocity is the velocity at which a
microscopic particle of dust would be traveling if it
were in the air stream.
In some instances, actual air velocity rather than
standard velocity may be of interest. To obtain the
value for actual velocity, multiply your standard
velocity by the following density correction factor: