Dear Javier: There are several parts to your question:- First, TRNSYS' conventions for the values of the variables. Michaël Kummert explained in a previous email that in TRNSYS, all variables are treated as "average values over the simulation time step (and the convention is that values are reported at the end of the time step). So if TRNSYS outputs an ambient temperature of 2.32 at TIME=2, it means the average temperature between 01:00 and 02:00 on January 1st was 2.32." I would recommend that you follow the email thread in the emailing list archive:
https://www.cae.wisc.edu/pipermail/trnsys-users/2005/000785.html http://sel.me.wisc.edu/trnsys/mailinglist/archive1999-2002/msg00735.html- Second, the use of the proforma for Type9. When you place an empty Type9 component from the Direct Access tree, you will see that there are only 10 parameters. Parameter 3 asks for 'Number of values to read', and the default value is 1. The Parameters 5 to 8 are telling the handling instructions for the input 1 in the data file. If you change Parameter 3 to N, the lines (5+(n-1)) to (8+(n-1)), for n=1...N, are the corresponding instructions for each input in the data file.
- Third, and finally, the answer to your question: -- If the column n in your data file was recorded as an average value during the the time step in the file, you do not want TRNSYS to average it for you one more time. Therefore, Parameter (8+(n-1)) = 0. If the column n has an instantaneous value, the other components expect from Type9 an average over the time step; therefore, you should specify Paremeter(8+(n-1))=1, so Type9 calculates the average. -- If you use the same time-step for your simulations and for your data input file, you do not need to interpolate between data points. Remember, this is independent from the averaging procedure explained above. If your simulation uses a smaller time step, you may want to interpolate between data points; setting Parameter (5+(n-1)) to 1.
One test that you can perform is to set these parameters in order to see in TRNSYS the same values that you had in your input file. This means that you assume that the values in your data file are averages during the time step, and that you are going to use the same time step for your simulations as for your input file. Use Parameter (5+(n-1))= -1, and Parameter (8+(n-1)) = 0, for all of the inputs in your data file. By doing this, you will see the exact same data from your input file.
I hope this helps. Please let me know if you have additional questions. Best regards, Diego javier mota wrote:
Dear all: I am Javier Mota from 3i -ingenieria madrid in spainWe are working with weather files, with data taken from zaragoza, a city in spain.This data has been got with empirical and hourly measures. So i will use type 9a to read the data. Parameter 8 sayss: average or instantameous value-1.I remenber that parameter 8 used with parameter5,( interpolate or not), makes that data usedis not the same that the data fron the original file.So, my qwestion is:Parameter8,average or instantameous value-1, may have some relation with the way empirical data were got?. So,if empirical data are average data in an hour. I must useparameter 8 as average and interpolate or not.Or simply, This has no sense, and parameter 8 may be instantaneous value even when the data file refers to averahe vaslues in time. So, When mus I used average or instantaneous and in relation with parameter 8 how i mus workwith parameter5, interpolate or not. Thanks in advance. _________________________________________________________________Descubre la descarga digital con MSN Music. Más de medio millón de canciones. http://music.msn.es/_______________________________________________ TRNSYS-users mailing list TRNSYS-users@engr.wisc.edu https://www.cae.wisc.edu/mailman/listinfo/trnsys-users