Endress+Hauser dosimass, Руководство по эксплуатации

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Dosimass Technical data
Hauser 37
Pressure loss (SI units) Pressure loss depends on the fluid properties and on the flow rate. The following formulas can be
used to approximately calculate the pressure loss:
Pressure loss coefficients:
A0008556
Fig. 19: Pressure loss diagram with water
Pressure loss (US units) Pressure loss ist dependent on fluid properties nominal diameter. Consult Hauser for
Applicator PC software to determine pressure loss in US units. All important instrument data is
contained in the Applicator software programm in order to optimize the design of measuring system.
The software is used for following calculations:
• Nominal diameter of the sensor with fluid characteristics such as viscosity, density, etc.
• Pressure loss downstream ot the measuring point.
• Converting mass flow to volume flow, etc.
• Simultaneous display of various meter size.
• Determining measuring ranges.
The Applicator runs on any IBM compatible PC with windows.
Reynolds number
Re

2300
Re < 2300

p = pressure loss [mbar]

= kinematic viscosity [m
2
/s]
g = mass flow [kg/s]

= density [kg/m
3
]
d = inside diameter of measuring tubes [m]
K to K2 = constants (depending on nominal diameter)
DN d [m] K K1 K2
8 5.35 · 10
–3
5.70 · 10
7
7.91 · 10
7
2.10 · 10
7
15 8.30 · 10
–3
7.62 · 10
6
1.73 · 10
7
2.13 · 10
6
25 12.00 · 10
–3
1.89 · 10
6
4.66 · 10
6
6.11 · 10
5
Pressure loss data including interface between measuring tubes and piping
R e =
2 ·
g
p n r
· d · ·
D r
p = K · · ·
0 . 25 1 . 85 – 0 . 86
g
n
D
p = K 1 · · + g
n
K 2 · ·
0 . 25 2
g
n
r
DN 25
DN 8
10000
1000
100
10
1
0.1
0.001
0.01
0.1
1
10
100 1000
DN 15
[mbar]
[t/h]