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: Sep 15, 2026
@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...
@ken, The short answer is that I would recommend making sure that the two surfaces have the same slope and azimuth. The longer answer is that ...
@jolind Type362 is a radiator model that was written by Transsolar. I have not used it. There is more information about it available at www.trnsys.d...
@humbertosantos Humberto, I am sure that I am missing some nuances of what you are trying to do but if you use an equation to add the heat pump's powe...
Luis, Type48 can be a bit tricky and on the many times that it was doing something confusing and I took the time to walk through the code a line a...
@takaya14 I have seen a few approaches to this issue. When the screen is open and there is a large horizontal opening then in the real world situa...
@tagreedwael Typically you would set up the active layer in TRNBuild so that it has an inlet temperature and mass flow rate defined as inputs to Typ...
@antonio Type560 is a bit more of the theoretical model but the principles are more or less the same. If you have one panel and want to add a second...
@xenia-kirschstein thanks for posting this announcement and for contributing to the community! ~david
@sw17032 sorry for the delay in getting back to you. If there is a difference between the inlet and outlet temperature, even if it is very small the...