.TransiEnt.Producer.Heat.SolarThermal.Base.GHI_Splitter

Information

1. Purpose of model

This model calculates the diffuse fraction of measured GHI d, to estimate the diffuse and direct fraction of GHI onto a horizontal surface. The user can choose between serveral empiric models to calculate the diffuse fraction (Skartveit and Olseth [1], Erbs, Orgill and Hollands or Reindl et al. [2]). The calculation of direct and

diffuse irradation from GHI is highly inaccurate.

2. Level of detail, physical effects considered, and physical insight

(Description)

3. Limits of validity

(Description)

4. Interfaces

irradiance_diffuse_horizontal: output for irradiance in W/m2

GHI_input: input for irradiance in W/m2

irradiance_direct_horizontal: output for irradiance in W/m2

5. Nomenclature

(no elements)

6. Governing Equations

(no equations)

7. Remarks for Usage

(none)

8. Validation

(no validation or testing necessary)

9. References

[1] Skartveit, Arvid; Olseth, Jan Asle, "A model for the diffuse fraction of hourly global radiation". In: Solar Energy 38 (4), S. 271–274. DOI: 10.1016/0038-092X(87)90049-1, 1987.

[2] PVPerformance Modeling Collaborative, "Piecewise Decomposition Models", URL: https://pvpmc.sandia.gov/modeling-steps/1-weather-design-inputs/irradiance-and-insolation-2/direct-normal-irradiance/piecewise_decomp-models, 2018.

10. Version History

Model created by Oliver Schülting (oliver.schuelting@tuhh.de), May 2018