Welcome to the TRNSYS Users Forum.
The forum is a place where people can interact and have discussions about different topics involving the use of the TRNSYS software package. Here you can post topics for discussion or questions on using TRNSYS and get advice from other users or TRNSYS experts. This forum is not intended for detailed technical support. Users should contact their distributor’s hotline for such assistance.
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Last seen: Apr 29, 2026
@karaktus I managed to find the report I wrote about that project (it was 2005!) and apparently at the time there was very little data to be found abo...
@karaktus It appears that the other two files are unintentionally missing from the install package. I will need to dig back through some very old arch...
@antonio could you please send your project file (*.tpf) and any other files needed in order to run the simulation to your distributor? If you are not...
@ken I think at the end of the day Type45 has a limited (and not ideal) treatment of IAMs. Other collector models have been brought up to date with mo...
@papillon Philippe, as a follow up to my earlier response I can confirm that you can recompile the TRNDll using the Intel IFX compiler and that the ...
@yalikara yes, that solution is perfectly acceptable for your use case! ~david
@medtab @mariem-s thank you, Mohamed for helping out. As a side note Mariem, you can also send the *.idf to your TRNSYS distributor for direct help.
Silvia, (@silviac) I usually draw the gross window area (glazing + frame) in SketchUp. For the benefit of users who haven't gone through this yet,...
Philippe, (@papillon) We are working on some trials of compiling Trnsys with the IFX compiler and hope to have some information out soon. As a side...
thanks for the suggestion @georgekyr. Would you be open to a more in depth conversation about this? ~david
@yalikara Unfortunately a fix needs to be made to the proforma, which can be done at the standard user level. If you'd like, here are the steps: 1...
@ken If I am reading the plot correctly the linear curve fit if IAM vs S is going to underpredict the IAM at near-normal incidence angles (meaning y...
@yalikara Either of your proposed solutions would work. If you do not plan to change the air flow rate during your simulation then your first sugges...
@bartolome this has been a long standing problem and (as far as I know) the only workaround is to treat the wall as though it were only a thermal re...
@ken Type45's incidence angle modifier is of the form IAM = 1 - b0 * S, where S = (1/cos(incidence angle)-1) What I would recommend is that you ta...