AixLib.Fluid.SolarCollectors.Controls.CollectorPump

# .AixLib.Fluid.SolarCollectors.Controls.CollectorPump

Controller which activates a circulation pump when solar radiation is above a critical level

## Information

Pump on/off controller for a solar thermal system.

This controller outputs whether the pump should be commanded on or off based on the incident solar radiation, the collector inlet temperature, and the system parameters. The pump is commanded on when the incident solar radiation is greater than the critical radiation plus the offset `delQ_flow`, and it is switched off if the incident solar radiation is below the critical radiation.

The critical radiation is defined per Equation 6.8.2 in Duffie and Beckman (2006). It is

GTC=(FRUL (TIn-TEnv)) /(FR(τα))

where GTC is the critical solar radiation, FRUL is the heat loss coefficient, TIn is the inlet temperature, TEnv is the ambient temperature, and FR(τα) is the maximum efficiency.

#### References

J.A. Duffie and W.A. Beckman 2006, Solar Engineering of Thermal Processes (3rd Edition), John Wiley & Sons, Inc.

## Revisions

- February 15, 2024, by Jelger Jansen:
  Refactor model.
  This is for Buildings, #3604.
- November 7, 2022, by Michael Wetter:
  Corrected implementation to make comparison based on total irradiation on tilted surface rather than the direct normal irradiation. This required adding parameters for the azimuth, tilt and ground reflectance.
  Changed output from continuous signal to boolean on/off signal as the old implementation run the pump possibly at very small flow rates. Moved old model to `AixLib.Obsolete` package.
  This is for issue 3074.
- January 15, 2013 by Peter Grant:
  First implementation.

Generated at 2026-05-09T18:18:56Z by OpenModelicaOpenModelica 1.26.7 using GenerateDoc.mos