Sierra INNOVA-MASS 241-VTP - Manual (Page 12)

Chapter 1 Introduction Series 24-HP Instruction Manual
1-6 IM-24-HP
As shown in Figure 1-3, Innova-Mass™ meters exhibit a constant
Strouhal number across a large range of Reynolds numbers, indicating a
consistent linear output over a wide range of flows and fluid types. Be-
low this linear range, the intelligent electronics in Innova-Mass automat-
ically corrects for the variation in the Strouhal number with the Reynolds
number. The meter’s smart electronics corrects for this non-linearity via
its simultaneous measurements of the process fluid temperature and pres-
sure. This data is then used to calculate the Reynolds number in real
time. Innova-Mass meters automatically correct down to a Reynolds
number of 5,000.
0.3
0.2
0.1
0.0
3 4 10
Linear range
Reynolds Number, Re
Strouhal Number, St
10 5 10 10 8 10 6 10 7
5000
Corrected range
Figure 1-3. Reynolds Number Range for the Innova-Mass
Temperature Measurement
Innova-Mass Flow Meters use a 1000 ohm platinum resistance temperature
detector (PRTD) to measure fluid temperature.