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atmospheric attenuation: hourly input with macros?

  • Luca S
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12 Apr 2017 07:17 #5336 by Luca S
atmospheric attenuation: hourly input with macros? was created by Luca S
The aerosol concentration in the air and thereby the atmospheric attenuation between heliostats and receiver varies over the time. It would be great to be able to simulate the annual yield of a power tower plant with hourly or at least daily values for the aerosol concentration. As far as I understand this possibility is not yet implemented in SAM. So before diving really deep into the macro scripting (which I did not use until now) my question is as follows:
Would it generally be possible to use the macro feature (and the scripting with LK) to force SAM to recalculate the atmospheric attenuation value for every single hour (or day) and use it in simulation?

Thank you for your time!

Best Regards,
Luca

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  • pgilman
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12 Apr 2017 21:27 #5337 by pgilman
Replied by pgilman on topic atmospheric attenuation: hourly input with macros?
Dear Luca,

SAM's power tower models calculate an average attenuation loss using a polynomial equation described in the Heliostat Field Help topic with coefficients that you can change on the Heliostat Input page.

SAM's LK script allows you to set the value of SAM inputs, run an annual simulation (at a time step determined by the time step of the weather file), and read the value of outputs. It does not allow you to change the values of intermediate variables during the course of a simulation, or to run a simulation one time-step at a time.

The best I can suggest would be to determine the polynomial coefficients that best represent the average attenuation over the entire field for your application.

Best regards,
Paul.

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