Dear Nicola, I am not quite sure if I interpretted this correctly across our Italian-English barrier; however, I will offer some tips about choosing an appropriate time step. First, a good rule-of-thumb is to keep your timestep in the units of hours. You can do this either by assigning an appropriate decimal (i.e. 0.125 hr for 7.5 minutes) or by using a string like the attached jpeg (i.e. 5/60 for a 5 minute timestep, 1/60 for a 1 minute timestep, 25/3600 for a 25 second timestep, etc.). In another note about timesteps, please realize that controllers in your simulation will make a control decision once per timestep. Thus, you would not want to have a 1 hr timestep if you have a controller in your simulation. Last, if you are concerned about how low you can bring your timestep, simply decrease it until you notice the results are uneffected or do not change much. Best regards, Matt Duffy ----- Original Message ----- From: "Nicola Sorbi Unipg" <nicolasorbi@mach.ing.unipg.it> Sent: Wed, September 23, 2009 5:24 Subject:[TRNSYS-users] Time Step Dear all, I have a question: Who the Time Step influences the simulation results? I have trouble in choosing the correct Time step!!! Regards Dott. Ing. Nicola Sorbi UNIVERSITA' DEGLI STUDI DI PERUGIA Dipartimento di Ingegneria Industriale Via G. Duranti 1A/4 - 06125 Perugia Tel. +39 075/5853930 - Fax. +39 075/5853736 E-mail nicolasorbi@mach.ing.unipg.it _______________________________________________ TRNSYS-users mailing list TRNSYS-users@cae.wisc.edu https://www-old.cae.wisc.edu/mailman/listinfo/trnsys-users ----- End of original message -----
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