Re: [TRNSYS-users] Slow model at boiler pressure of 10000kPa

Hi Jeff

Thanks for the email

I am using TRNSYS 18

If you want to replicate the issue, simply useType58 and put P=10000kPa and h=940 kJ/kg and you will get both issues: 1- super slow simulation 2- odd steam quality value of -1.5e38

Thanks

Best Regards,

Amir Nashed, PhD

Energy Engineer

Estate Management

UNSW SYDNEY NSW 2052 AUSTRALIA

E: a.nashed@unsw.edu.au

T: +61 2 9385 3401

M: +61 4 0597 9282

W: www.estate.unsw.edu.au

CRICOS Provider Code 00098G

From: Jeff Thornton <thornton@tess-inc.com>
Sent: Wednesday, 14 August 2019 1:25 AM
To: TRNSYS users mailing list at OneBuilding.org <trnsys-users@lists.onebuilding.org>
Cc: Amir Nashed <a.nashed@unsw.edu.au>
Subject: Re: [TRNSYS-users] Slow model at boiler pressure of 10000kPa

Amir,

Which version of TRNSYS are you using? I know we identified and fixed an issue within the steam properties subroutine a few months back that might be the cause for your issue.

Jeff - TESS

Sent from my iPhone

On Aug 12, 2019, at 6:56 PM, Amir Nashed via TRNSYS-users <trnsys-users@lists.onebuilding.org> wrote:

Dear TRNSYS users

For some reason all steam components at P=100 Bar (10,000 kPa) go very slow, whether it is a preheater, condensate pump..etc

The issue is not with the model, as I isolated the components, for example simulated type609 by itself and still did not work. . I believe the reason is the the Steam_Properties() subroutine as when I tried to use Type58 just by itself at the same steam properties, the same issues occurred. When I reduce the pressure to 9300 kPa, it works fine.

Inputs:

<image002.jpg>

Does anyone know how to solve that?

I can change the pressure, but I believe 100 bars for boiler pressure is pretty standard

Best Regards,

Amir Nashed, PhD

Energy Engineer

Estate Management

UNSW SYDNEY NSW 2052 AUSTRALIA

E: a.nashed@unsw.edu.au

T: +61 2 9385 3401

M: +61 4 0597 9282

W: www.estate.unsw.edu.au

CRICOS Provider Code 00098G

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