Error Result during PTC Simulation.

When the Solar field inlet temperature( Therminol VP-1) is reduced below 280 deg , for an outlet temperature of 391, a error result is displayed half way through the compilation.

Our version is 2013.1.15 Revision 2. already updated with the latest patch provided by the system update.

Works fine when the inlet Solar field temperature is above 280 and solar outlet field temp is 390.That is effective delta T is around 100 degs.

Pls check the Attached file for further Info on the same.

Error Msg Displayed as follows.

---

SAMSIM MESSAGES

---

MSG[0]: SVAL LOOKUP ERROR trnsys.user_trdsrc
MSG[1]: SVAL LOOKUP ERROR trnsys.user_exe_deck_enabled
MSG[2]: SVAL LOOKUP ERROR trnsys.user_exe_deck_enabled
MSG[3]: SVAL LOOKUP ERROR trnsys.user_exe
MSG[4]: SVAL LOOKUP ERROR trnsys.user_args
MSG[5]: TrnModel::ReadOutput[ncol=72 nalloc=8760 lnchars=3800] = 74 msec
MSG[6]: TrnModel::ReadOutput[ncol=24 nalloc=12 lnchars=2400] = 1 msec
MSG[7]: TrnModel::ReadOutput[ncol=20 nalloc=2 lnchars=1800] = 0 msec
MSG[8]: SVAL LOOKUP ERROR trnsys.target_hourly_folder
MSG[9]: TrnModel Notice: Deleting file 'C:/Users/GuessWho/AppData/Local/SAMEXE/SAMEXE-GuessWho-INST1-2013.1.15/simdata/My_project/BASE/trough.hourly.out'

MSG[10]: BADTYPE OUTPUT system.annual.gross_electric_generation
MSG[11]: BADTYPE OUTPUT system.annual.e_net
MSG[12]: BADTYPE OUTPUT system.annual.q_dni_on_sf
MSG[13]: BADTYPE OUTPUT system.annual.qsf_nipcosth
MSG[14]: BADTYPE OUTPUT system.annual.sfavailableenergy
MSG[15]: BADTYPE OUTPUT system.annual.qsf_abs
MSG[16]: BADTYPE OUTPUT system.annual.qsf
MSG[17]: BADTYPE OUTPUT system.annual.q_to_pb
MSG[18]: BADTYPE OUTPUT system.annual.qsf_pipe_hl
MSG[19]: BADTYPE OUTPUT system.annual.qsf_hce_hl
MSG[20]: BADTYPE OUTPUT system.annual.q_tes_full
MSG[21]: BADTYPE OUTPUT system.annual.q_tes_hl
MSG[22]: BADTYPE OUTPUT system.annual.q_turb_su
MSG[23]: BADTYPE OUTPUT system.annual.fuel_usage

---

TRNSYS LOG FILE

---

TRNSYS - the TRaNsient SYstem Simulation program

The Solar Energy Lab at the University of Wisconsin - Madison, USA
Le Centre Scientifique et Technique du Batiment, Sophia Antipolis, France
Transsolar Energietechnik GmBH, Stuttgart, Germany
Thermal Energy System Specialists, Madison Wisconsin, USA

Release 16.xx.xxxx

Simulation log for: "C:/Users/GuessWho/AppData/Local/SAMEXE/SAMEXE-GuessWho-INST1-2013.1.15/simdata/My_project/BASE/trnsys.trough.trd"

*** Notice at time : 0.000000
Generated by Unit : Not applicable or not available
Generated by Type : Not applicable or not available
Message : The TRNSYS Executable (TRNExe.exe) and main DLL (TRNDll.dll) are located in "."

*** Fatal Error at time : 1382.000000
Generated by Unit : 8
Generated by Type : 805
Message : CSP Trough model exceeded internal iteration limit.

*** An error has forced TRNSYS to abort


*** Simulation stopped with errors
Total Notices : 1
Total Warnings : 0
Total Fatal Errors : 1

Hello,

SAM generates this message for the Empirical Trough Model when the iterative algorithm that calculates the solar field temperatures is unable to converge on a solution for the inlet and outlet temperatures that is within a certain tolerance of the design inlet and outlet temperatures. In your case, when you specify a design inlet temperature of less than 280 degrees C with a design outlet temperature of 391 degrees C, given the solar resource for New Delhi, there may be insufficient solar energy to heat the HTF to the design point.

The empirical trough model is intended for systems that are similar in design to the SEGS plants in the southwestern United States. It may be that the SEGS design is not suitable for the location you are modeling.

If you would like to model a parabolic trough system with a different design, you could try using the physical trough model instead.

Best regards,
Paul.