KROHNE CORIMASS MFC 85 EN User Manual
Page 12
12
Temperature °C
Density
1st Point
T
1
ρ
1
2nd Point
T
2
ρ
2
Set: Fct. 3.10.4 LIQUID
=
NON WATER
Fct. 3.10.7 LIQUID K2
=
0
Fct. 3.10.6 LIQUID K1
=
ρ
ρ
1
2
1
2
−
−
T
T
Fct. 3.10.5 LIQUID R20
=
(
)
ρ
1
1
1
20
−
−
K T
To fully fit the temperature compensation equation to the real fluid three different temperature /
density points are required; (
ρ
1
,T
1
), (
ρ
2
,T
2
), and (
ρ
3
,T
3
). This gives a set of three equations
with three unknowns to be solved simultaneously.
(
)
(
)
(
)
(
)
(
)
(
)
ρ
ρ
ρ
ρ
ρ
ρ
1
20
1
1
2
1
2
2
20
1
2
2
2
2
3
20
1
3
2
3
2
20
20
20
20
20
20
=
+
−
+
−
=
+
−
+
−
=
+
−
+
−
K T
K T
K T
K T
K T
K T
Manual solution of these equations is possible, especially if one of the temperatures T
1
,T
2
or
T
3
= 20°C. However this is tedious and mistakes are easily made. It is recommended that the
Microsoft Excel
spread sheet file CONC4.XLT should be used to solve these equations
automatically.
Should a PC running Microsoft Excel
version 5 or later not be available the solution of these
equations is as follows:
(
)
(
)
(
)
(
)
(
)
(
)
K
T
T
T
T
T
T
T
T
T
T
T
T
T
T
T
K
K T
K T
T
T
K T
K T
2
1
3
2
2
1
3
3
2
1
3
2
2
1
2
2
1
3
1
2
3
2
1
1
2
2
1
2
2
2
2
1
2
20
1
1
1
2
1
2
20
20
20
20
=
−
+
−
+
−
−
+
−
+
−
=
−
−
−
+
−
−
=
−
−
−
−
ρ
ρ
ρ
ρ
ρ
ρ
ρ
(
)
(
)
(
)
(
)
Case 3:
Oil Water Emulsions
For this case the oil should be treated as the “solid” component, and the LIQUID (Fct. 3.10.4)
should be set to WATER. The calculation of the oil’s density parameters (Fct. 3.10.1 - 3) are
calculated in the same way as described for the liquid carrier in Case 2 above.