KROHNE OPTISWIRL 4070 EN - Manual (Page 15)

DEVICE DESCRIPTION
2
15
OPTISWIRL 4070
www.krohne.com 02/2013 - 4000150606 MA OPTISWIRL4070C R07 en
2.2.7 Gross heat meter
In almost all applications with saturated steam, the steam is used for heating. It is much more
interesting to know how great the heat flow volume is that is available to the process, than to
know how great the flow is in kg/h.
As the enthalpy of steam changes with the temperature, it cannot be assumed as a constant. The
vortex flowmeter has a special feature that can calculate the flow of vapour and water as power
output. The enthalpy tables are permanently programmed in the memory of the device.
The online density-compensated mass flow is multiplied by the correct enthalpy to obtain the
flow as power output.
Power {Q
H
] = mass flow [Q
m
] x enthalpy [H]
If the gross heat meter is activated, both the totalizer for the absolute steam consumption as
well as that for the energy run internally.
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