VorTek Pro-T, Инструкция по эксплуатации

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Series M22/M23/M24 Instruction Manual Chapter 1 Introduction
M-000-00010 1-5
Re =

V D

Flow Velocity Range
To ensure trouble-free operation, vortex flow meters must be correctly
sized so that the flow velocity range through the meter lies within the
measurable velocity range (with acceptable pressure drop) and the linear
range.
The measurable range is defined by the minimum and maximum velocity
using the following table.
Gas Liquid
Vmin
25

ft/s
1 ft/s
English

(lb/ft 3 )
Vmax
0.5 in
0.75 in
1 in
1.5 in and
greater
175 ft/s
250 ft/s
250 ft/s
300 ft/s 30 ft/s
30 ft/s
30 ft/s
30 ft/s
Vmin
3 7

m/s 0.3 m/s
Metric

(kg/m
3
)
Vmax
DN15
DN20
DN25
DN40 and
greater
53 m/s
76 m/s
76 m/s
91 m/s 9.1 m/s
9.1 m/s
9.1 m/s
9.1 m/s
The linear range is defined by the Reynolds number. The Reynolds number is the
ratio of the inertial forces to the viscous forces in a flowing fluid and is defined
as:
Where
Re = Reynolds Number

= mass density of the fluid being measured
V = velocity of the fluid being measured
D = internal diameter of the flow channel

= viscosity of the fluid being measured