User-Defined Power Block

Hi.
I dealing with some problems defining my ORC...
The user-defined power block is based on the performance as function of 3 parameters. 
Relatively to HTF temperature and HTF mass flow rate, this HTF is the solar field fluid or powerblock fluid? 
As we need to normalize HTF mass flow rate, which value is the minimum and maximum? Is the "min/max single loop flow rate"  defined in Solar Field divided by "Cycle design HTF mass flow rate" value in Power Cycle?

I can't find it explained in any document...

Best regards,
Bernardo.

Hi Bernardo,

The draft description of the user-defined power cycle model describes these parameters: sam.nrel.gov/images/web_page_files/Neises-DRAFT-user-defined-power-cycle-v4-2021.pdf

The HTF parameter values describe the power cycle HTF. The relationship between the design values of the solar field and power cycle HTF are discussed under "Custom Cycle Design Point Performance" on p. 2.

The role of "low" and "high" values are described under "Sampling the Custom Power Cycle Model" on p. 3.

Best regards,
Paul.

Hi Paul!
Now I understand that HTF values in User-Defined Power Cycle are about power cycle fluid, but the value of "Cycle design HTF mass flow rate" is referent to solar field fluid...
So, the design value of HTF mass flow rate in User-Defined Power Cycle that we need to use to normalize mass flow is based on our ORC data, right? SAM doesn't give us that value, is that correct?

I am confused because SAM uses HTF to talk about different fluids...

Best regards,
Bernardo.

Hi Bernardo,

Yes. The term "HTF" for the user-defined power cycle model data refers to the power cycle fluid. In your case that would be your ORC data.

Best regards,
Paul.

Hi Paul.
Understood, thanks.

Best regards,
Bernardo.

Hi Paul.

Just a doubt about the HTF of the power cycle.

The HTF cold temperature exiting the power cycle is calculated by: 



As the HTF is the power cycle fluid, where do we define cp?

In Neises It says that: "Because SAM’s technology models depend on the relationship between temperatures, mass flow rate, and thermal power to balance mass and energy between component, it is important that the custom cycle model is assuming HTF properties corresponding to the HTF selected in the SAM user interface (UI)."

Best regards,
Bernardo.