[Bug] Pipe section temperature change calculation error

[garethshaw100-tech]

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Describe the bug
A pipe section calculation named Riser (in attached flowsheet) reports a temperature change of -0.677517 C (negative) but the inlet temperature of 24.922 C increases to 25.5995 C. Temperature change is expected to be negative due to exolution of CH4 and CO2 in water as pressure is reduced in the riser. The error is not just nomenclature as the temperature increase is carried forward in following calculations.

The temperature change reported for the cooling water pump (in the same attached flowsheet) reports a temperature change 12.2339 C (positive) and the CW inlet temperature increases from 25 C to 37.2339 C confirming that there is no error in the pump calculation nor the nomenclature.

To Reproduce

PLEASE ATTACH THE ZIPPED FLOWSHEET FILE and/or inform the steps to reproduce the behavior:

1. Go to 'Riser'
2. Hover over Riser to read pipe section calculation summary
3. Note Temperature change reported is negative -0.677517 C
4. Go to Feed Liq and read inlet temp of 24.922 C
5. Go to steam 6 (Riser outlet) and read temperature of 25.5995 C
6. Note -0.677517 C temperature reported in calculation summary does not reduce outlet temperature but rather increases the outlet temperature.

Expected behavior
Exolution of CH4 and CO2 from degassing water due to depressurisation should drop outlet temperature.

Screenshots
If applicable, add screenshots to help explain your problem.

Riser pipe query for DWsim.zip

Desktop (please complete the following information):

• OS: Windows 11 Pro
• Version 23H2

Additional context
Add any other context about the problem here.

[DanWBR]

@ garethshaw100-tech you would need to tune up the binary interaction parameters for the selected thermo model. This may need a specialized model that DWSIM doesn't have.