modelBorefield
Extends from Buildings.Obsolete.BaseClasses.ObsoleteModel, Buildings.Fluid.Interfaces.PartialTwoPortInterface.
Information
This is a model for a borefield system with a variable speed pump and a mixing valve modulated to maintain a maximum inlet temperature.
The system is controlled based on the logic described in Buildings.Obsolete.DHC.ETS.Combined.Controls.Borefield. The pump flow rate is considered proportional to the pump speed under the assumption of a constant flow resistance in the borefield loop. This assumption is justified by the connection of the loop to the buffer tanks, and by the additional assumption that the bypass branch of the mixing valve is balanced with the direct branch.
(The parameter from_dp of the valve model is set to false to
simplify the system of algebraic equations, which, in this specific case,
alleviates non-convergence issues.)
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Fluid.Geothermal.Borefields.Data.Borefield.Example | datBorFie | ||
| Modelica.Units.SI.Pressure | dpValBorFie_nominal | dp_nominal/2 | Nominal pressure drop of control valve |
| Modelica.Units.SI.Temperature | TBorWatEntMax | Maximum value of borefield water entering temperature | |
| Real | spePumBorMin | 0.1 | Borefield pump minimum speed |
| Nominal condition | |||
| Modelica.Units.SI.Pressure | dp_nominal | Pressure losses for the entire borefield (control valve excluded) | |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.RealInput[2] | yValIso_actual | Isolation valves return position (fractional) | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | u | Control signal from supervisory | |
| Buildings.Fluid.Actuators.Valves.ThreeWayEqualPercentageLinear | val | Mixing valve controlling entering temperature | |
| Buildings.DHC.ETS.BaseClasses.Pump_m_flow | pum | Pump with prescribed mass flow rate | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTEnt | Entering temperature | |
| BorefieldType | borFie | Geothermal borefield | |
| Buildings.DHC.ETS.BaseClasses.Junction | spl | Flow splitter | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTLvg | Leaving temperature | |
| Buildings.Obsolete.DHC.ETS.Combined.Controls.Borefield | con | Controller | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | PPum | Pump power | |
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai1 | Scale to nominal mass flow rate |
Contents
| Name | Description |
|---|---|
| BorefieldType |