Mould growth risk: Isopleth model results

[gismo]

Dear Delphin team,

I'm evaluating the risk of mould growth on an internal surface for three different scenarios (different indoor conditions and wall assembly).
To do that, I'm using two models available in POSTPROC2: Isopleth model and VTT mould model.

I would like to better understand how the software calculates the number of mould risk days generated by the Isopleth model, as they are not consistent with what I graphically read. For example, Scenario 1 shows a large number of points that exceed the germination limits, but the legend reports only 0.12 days exceeding the red limit for germination. On the other hand, Scenarios 2 and 3 show a lower amount of exceeding points, with a different distribution among the germination limits, but their legends report a largely higher number of mould risk days subdivided among the six categories.

Scenario1-Isopleth.png (24.06 KiB) 35554 mal betrachtet

Scenario2-Isopleth.png (25.29 KiB) 35554 mal betrachtet

Scenario3-Isopleth.png (25.3 KiB) 35554 mal betrachtet

As far as I understand, I can find better matches with the graphical Isopleth output by analysing the VTT model results, which show the highest risk for Scenario 1 (avg Mould Index = 3.5), followed by Scenario 2 (avg Mould Index = 3.2) and 3 (avg Mould Index = 2.8).

To better read the attached graphs, here are some settings:
- simulation time frame: 10 years
- averaging isopleth plot: 96 h (4 days)

Thank you in advance for your support,

[fechner]

Hello,

May you can attach also the project file. I would like to recalculate the results in order to evaluate what happens here.

[fechner]

and I will check the code.

[gismo]

Dear fechner,

The .zip folder includes the project file, customised climate conditions and a couple of edited materials.

The three charts refer to the internal surface (Sc.3) and to the two surfaces facing the air cavity: outer srf (Sc.1) and inner srf (Sc.2).

Let me know if everything is readable or if any input files are missing.

[fechner]

Hello,

Nothing is missing and I can run the calculation. But my isopleth charts look different. Do you used averaging? Do you have limited the isoplet points to a certain time period?

[gismo]

Yes, I applied these settings:
- simulation time frame: 10 years
- averaging isopleth plot: 96 h (4 days)

[fechner]

Ok, there is a bug in the calculation algorithm for the mould risk times in isopleth model. I will fix it and send you a link to the new version by email. I will also put the new version on our server for download as soon as possible.

[gismo]

Hello, everything is clear now!
Thank you for your kind and fast support