Endress+Hauser HART Proline Promass 80, Operating Instructions Manual

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Technical data Proline Promass 80
96 Hauser
Pressure loss (SI units) Pressure loss depends on the properties of the fluid and on its flow. The following formulas can be
used to approximately calculate the pressure loss:
Pressure loss formulas for Promass F, E
Pressure loss formulas for Promass H, I, S, P
Pressure loss formulas for Promass A
Reynolds number
a0004623
Re

2300
1)
a0004626
Promass F DN 250
a0012135
Re < 2300
a0004628

p = pressure loss [mbar]

= kinematic viscosity [m
2
/s]
g = mass flow [kg/s]

= fluid density [kg/m
3
]
d = inside diameter of measuring tubes [m]
K to K2 = constants (depending on nominal diameter)
1)
To compute the pressure loss for gases, always use the formula for Re

2300.
Reynolds number
a0003381
Re

2300
1)
a0004631
Re < 2300
a0004633

p = pressure loss [mbar]

= kinematic viscosity [m
2
/s]
g = mass flow [kg/s]

= fluid density [kg/m
3
]
d = inside diameter of measuring tubes [m]
K to K3 = constants (depending on nominal diameter)
1)
To compute the pressure loss for gases, always use the formula for Re

2300.
Reynolds number
a0003381
Re

2300
1)
a0003380
Re < 2300
a0003379

p = pressure loss [mbar]

= kinematic viscosity [m
2
/s]
g = mass flow [kg/s]

= density [kg/m

]
d = inside diameter of measuring tubes [m]
K to K1 = constants (depending on nominal diameter)
1)
To compute the pressure loss for gases, always use the formula for Re

2300.
R e =
2 ·
g
p n r
· d · ·
D r p = K · · ·
0 . 25 1 . 85 – 0 . 86
g
n
D p = · K
a
1 - a +
e
· · · g
1 . 85 – 0 . 86
r
0 . 25
n
b · ( – 10 )
n
– 6
D
p = K 1 · · +
g n
K 2 · ·
0 . 25 2
g n
r
R e =
p n r
· d · ·
4 ·
g
K 3 · g
2
r
+
D
0 . 25
· g
1 .7 5
·
- 0 .7 5
n r
D p = K 1 · · g n
K 3 ·
g
2
r
+
R e =
p n r · d · ·
4 · g
D n r p = K · · ·
0 . 25 1 .7 5 – 0 .7 5
g
D n p = K 1 · ·
g