Junctions Explained
Coolselector®2
Morten Juel Skovrup
2019-10-25
Version 1.00
Explaining how to use junctions and how to interpret the performance details.
Junctions Explained
1 Junctions removing mass flow
Junctions are a piping element that can change the mass flow in a “Components in series” calculation.
If you for example have a liquid feed line in a pump system using R717 and you had the following 3 evaporators:
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Then the operating conditions could look like this – noting that the total cooling capacity (as seen from the liquid line inlet) is 100 kW:
Then the result of adding junctions might look like this:
The first junction removes 25 % of the line inlet mass flow, corresponding to 833.9 0.25 =208.5 kgh or a cooling capacity of 25 kW. This also means that the remaining mass flow is 625.4 kg/h corresponding to 75 kW cooling capacity.
The second junction also removes 25 % of the line inlet mass flow, corresponding to 833.9 0.25 =208.5 kgh or a cooling capacity of 25 kW. This is important to note: the mass flow that the junction adds or removes from the line, is always related to the line inlet mass flow. And the line inlet mass flow is only dependent on the selected operating conditions.
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