In heating or cooling processes of materials
and products using heat exchanger, the flow of heating or cooling medium
fed to the exchanger is measured as one of the basic data for monitoring
efficiency of the exchanger. The media feed line is usually designed with
a bypass installed right before the exchanger, in order to avoid flow changes
which cause variation of the media temperature (see the figure below).
The heating or cooling medium flow may be obtained by subtracting the bypass
flow (X2) from the pumping-out flow (X1).
The Math Function Module is used here for the calculation. In addition,
Isolators shown in the figure are used to prevent the electrical noise disturbance
caused by relay switching and other sources. |
