blockSupplyReturnTemperatureReset

Block to compute the supply and return set point

Extends from Modelica.Blocks.Icons.Block (Basic graphical layout of input/output block).

Information

This block computes the set point temperatures for the supply and return water temperature. The set point for the room air temperature can either be specified by a parameter, or it can be an input to the model. The latter allows to use this model with systems that have night set back.

If used to reset the temperature in a heating system, the parameter dTOutHeaBal can be used to shift the heating curve to take into account that heat gains from solar, equipment and people make up for some of the transmission losses. For example, in energy efficient houses, the heating may not be switched on if the outside air temperature is greater than 12°C, even if a room temperature of 20°C is required. In such a situation, set dTOutHeaBal=20-12=8 Kelvin to shift the heating curve.

Parameters

TypeNameDefaultDescription
Realm1.3Exponent for heat transfer
Booleanuse_TRoo_infalseGet the room temperature set point from the input connector
Modelica.Units.SI.TemperatureTRoo293.15Fixed value of room temperature set point
Modelica.Units.SI.TemperatureDifferencedTOutHeaBal8Offset for heating curve
Nominal conditions
Modelica.Units.SI.TemperatureTSup_nominalSupply temperature
Modelica.Units.SI.TemperatureTRet_nominalReturn temperature
Modelica.Units.SI.TemperatureTRoo_nominal293.15Room temperature
Modelica.Units.SI.TemperatureTOut_nominalOutside temperature

Connectors

TypeNameDefaultDescription
Modelica.Blocks.Interfaces.RealInputTRoo_inRoom air temperature set point
Modelica.Blocks.Interfaces.RealInputTOutOutside temperature
Modelica.Blocks.Interfaces.RealOutputTSupSetpoint for supply temperature
Modelica.Blocks.Interfaces.RealOutputTRetSetpoint for return temperature

Revisions

  • March 11, 2024, by Michael Wetter:
    Corrected use of HideResult.
    This is for #1850.
  • January 03, 2020, by Jianjun Hu:
    Changed name from HotWaterTemperatureReset to SupplyReturnTemperatureReset.
    This is for #1273.
  • May 29, 2014, by Michael Wetter:
    Removed undesirable annotation Evaluate=true.
  • February 13, 2013, by Michael Wetter:
    Corrected error that led to wrong results if the room air temperature is different from its nominal value TRoo_nominal. See ticket #74.
  • November 21, 2011, by Michael Wetter:
    Improved documentation.
  • February 5, 2009 by Michael Wetter:
    First implementation.