.Buildings.Fluid.HydronicConfigurations.PassiveNetworks.Examples.DualMixing

Information

This model represents a heating system where the configuration Buildings.Fluid.HydronicConfigurations.PassiveNetworks.DualMixing serves as the interface between a variable flow primary circuit and a constant flow secondary circuit. The secondary supply temperature is constant and lower than the primary circuit.

The fixed bypass of the dual mixing circuit is balanced at design conditions if kSizBal=1. Selecting a lower value such as kSizBal=0.6 illustrates the operation with an oversized balancing valve, yielding a lower pressure drop. One can observe that the secondary supply temperature set point cannot be met despite the control valve being fully open. The secondary distribution pump operates with sufficient head as the design flow rate is met in the consumer circuit. This is the low pressure differential at the boundaries of the control valve due to the oversized balancing valve that creates the primary flow shortage and prevents from serving the load properly.

Revisions

• June 30, 2022, by Antoine Gautier:
  First implementation.