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Modelica Buildings library
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Improve radiant floor controller #2823

Closed mwetter closed 2 years ago

mwetter commented 2 years ago

This issue is to improve the radiant floor controller Buildings.Controls.OBC.RadiantSystems.Cooling.HighMassSupplyTemperature_TRoomRelHum to use the surface temperature plus an offset for condensation control, rather than the supply water temperature that is currently used. (The current implementation is more conservative as it is not subject to the slab dynamics.)

This requires adding an output for the surface temperature near the pipe inlets in Buildings.Fluid.HeatExchangers.RadiantSlabs.SingleCircuitSlab (and in ParallelCircuitsSlab). This measurement can be taken from con_a[1].

Other control options that may be added in the future include shifting the supply temperature based on the outdoor temperature of the last day, and optionally adding pulse width modulation rather than constant flow for the pump, see for example https://doi.org/10.1016/j.apenergy.2009.01.008. Also, some systems seem to operate the cooling based on constant supply temperature (with added condensation control) and count on the self-regulation effect.

mwetter commented 2 years ago

The development branch is issue2823_radiantController.

Todo: Consider using the same base class for RadiantHeatingCooling_TRoom and RadiantHeatingCooling_TSurface. -- Will leave as is because this is easier for the user to understand and modify.