Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses
Base classes for Borehole
Information
This package contains base classes that are used to construct the models in Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.
Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).
Package Content
Name | Description |
---|---|
InternalHEXOneUTube | Internal heat exchanger of a borehole for a single U-tube configuration |
InternalHEXTwoUTube | Internal heat exchanger of a borehole for a double U-tube configuration. In loop 1, fluid 1 streams from a1 to b1 and comes back from a2 to b2. In loop 2: fluid 2 streams from a3 to b3 and comes back from a4 to b4. |
InternalResistancesOneUTube | Internal resistance model for single U-tube borehole segments. |
InternalResistancesTwoUTube | Internal resistance model for double U-tube borehole segments. |
PartialBorehole | Partial model to implement multi-segment boreholes |
PartialInternalHEX | Partial model to implement the internal heat exchanger of a borehole segment |
PartialInternalResistances | Partial model to implement borehole segment internal resistance models |
Functions | Package with functions for evaluation of borehole thermal resistances |
Examples | Example models to test base classes |
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.InternalHEXOneUTube
Internal heat exchanger of a borehole for a single U-tube configuration
Information
Model for the heat transfer between the fluid and within the borehole filling for a single borehole segment. This model computes the dynamic response of the fluid in the tubes, the heat transfer between the fluid and the borehole filling, and the heat storage within the fluid and the borehole filling.
This model computes the different thermal resistances present in a single-U-tube borehole using the method of Bauer et al. (2011) and computing explicitely the fluid-to-ground thermal resistance Rb and the grout-to-grout resistance Ra as defined by Claesson and Hellstrom (2011) using the multipole method.
References
J. Claesson and G. Hellstrom. Multipole method to calculate borehole thermal resistances in a borehole heat exchanger. HVAC&R Research, 17(6): 895-911, 2011.
D. Bauer, W. Heidemann, H. Müller-Steinhagen, and H.-J. G. Diersch. Thermal resistance and capacity models for borehole heat exchangers . International Journal Of Energy Research, 35:312-320, 2011.
Extends from Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalHEX (Partial model to implement the internal heat exchanger of a borehole segment), Buildings.Fluid.Interfaces.FourPortHeatMassExchanger (Model transporting two fluid streams between four ports with storing mass or energy).
Parameters
Type | Name | Default | Description |
---|---|---|---|
Template | borFieDat | Borefield parameters | |
replaceable package Medium | PartialMedium | Medium | |
Length | hSeg | Length of the internal heat exchanger [m] | |
Volume | VTubSeg | hSeg*Modelica.Constants.pi*(... | Fluid volume in each tube [m3] |
replaceable package Medium1 | PartialMedium | Medium 1 in the component | |
replaceable package Medium2 | PartialMedium | Medium 2 in the component | |
Nominal condition | |||
MassFlowRate | m1_flow_nominal | Nominal mass flow rate [kg/s] | |
MassFlowRate | m2_flow_nominal | Nominal mass flow rate [kg/s] | |
PressureDifference | dp1_nominal | Pressure difference [Pa] | |
PressureDifference | dp2_nominal | Pressure difference [Pa] | |
Dynamics | |||
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material |
Nominal condition | |||
Time | tau1 | VTubSeg*rho1_nominal/m1_flow... | Time constant at nominal flow [s] |
Time | tau2 | VTubSeg*rho2_nominal/m2_flow... | Time constant at nominal flow [s] |
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state |
Initialization | |||
Temperature | TFlu_start | Start value of fluid temperature [K] | |
Temperature | TGro_start | Start value of grout temperature [K] | |
Medium 1 | |||
AbsolutePressure | p1_start | Medium1.p_default | Start value of pressure [Pa] |
Temperature | T1_start | TFlu_start | Start value of temperature [K] |
MassFraction | X1_start[Medium1.nX] | Medium1.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C1_start[Medium1.nC] | fill(0, Medium1.nC) | Start value of trace substances |
ExtraProperty | C1_nominal[Medium1.nC] | fill(1E-2, Medium1.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Medium 2 | |||
AbsolutePressure | p2_start | Medium2.p_default | Start value of pressure [Pa] |
Temperature | T2_start | TFlu_start | Start value of temperature [K] |
MassFraction | X2_start[Medium2.nX] | Medium2.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C2_start[Medium2.nC] | fill(0, Medium2.nC) | Start value of trace substances |
ExtraProperty | C2_nominal[Medium2.nC] | fill(1E-2, Medium2.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Assumptions | |||
Boolean | allowFlowReversal1 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 1 |
Boolean | allowFlowReversal2 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 2 |
Advanced | |||
MassFlowRate | m1_flow_small | 1E-4*abs(m1_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
MassFlowRate | m2_flow_small | 1E-4*abs(m2_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
Diagnostics | |||
Boolean | show_T | false | = true, if actual temperature at port is computed |
Flow resistance | |||
Medium 1 | |||
Boolean | from_dp1 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance1 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM1 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Medium 2 | |||
Boolean | from_dp2 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance2 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM2 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Connectors
Type | Name | Description |
---|---|---|
HeatPort_a | port_wall | Thermal connection for borehole wall |
replaceable package Medium1 | Medium 1 in the component | |
replaceable package Medium2 | Medium 2 in the component | |
FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) |
FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) |
FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) |
FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.InternalHEXTwoUTube
Internal heat exchanger of a borehole for a double U-tube configuration. In loop 1, fluid 1 streams from a1 to b1 and comes back from a2 to b2. In loop 2: fluid 2 streams from a3 to b3 and comes back from a4 to b4.
Information
Model for the heat transfer between the fluid and within the borehole filling. This model computes the dynamic response of the fluid in the tubes, the heat transfer between the fluid and the borehole filling, and the heat storage within the fluid and the borehole filling.
This model computes the different thermal resistances present in a single-U-tube borehole using the method of Bauer et al. (2011) and computing explicitely the fluid-to-ground thermal resistance Rb and the grout-to-grout resistance Ra as defined by Claesson and Hellstrom (2011) using the multipole method.
References
J. Claesson and G. Hellstrom. Multipole method to calculate borehole thermal resistances in a borehole heat exchanger. HVAC&R Research, 17(6): 895-911, 2011.
D. Bauer, W. Heidemann, H. Müller-Steinhagen, and H.-J. G. Diersch. Thermal resistance and capacity models for borehole heat exchangers . International Journal Of Energy Research, 35:312-320, 2011.
Extends from Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalHEX (Partial model to implement the internal heat exchanger of a borehole segment), Buildings.Fluid.Interfaces.EightPortHeatMassExchanger (Model transporting four fluid streams between eight ports with storing mass or energy).
Parameters
Type | Name | Default | Description |
---|---|---|---|
Template | borFieDat | Borefield parameters | |
replaceable package Medium | PartialMedium | Medium | |
Length | hSeg | Length of the internal heat exchanger [m] | |
Volume | VTubSeg | hSeg*Modelica.Constants.pi*(... | Fluid volume in each tube [m3] |
replaceable package Medium1 | PartialMedium | Medium 1 in the component | |
replaceable package Medium2 | PartialMedium | Medium 2 in the component | |
replaceable package Medium3 | PartialMedium | Medium 3 in the component | |
replaceable package Medium4 | PartialMedium | Medium 4 in the component | |
Nominal condition | |||
MassFlowRate | m1_flow_nominal | Nominal mass flow rate [kg/s] | |
MassFlowRate | m2_flow_nominal | Nominal mass flow rate [kg/s] | |
MassFlowRate | m3_flow_nominal | Nominal mass flow rate [kg/s] | |
MassFlowRate | m4_flow_nominal | Nominal mass flow rate [kg/s] | |
Pressure | dp1_nominal | Pressure [Pa] | |
Pressure | dp2_nominal | Pressure [Pa] | |
Pressure | dp3_nominal | Pressure [Pa] | |
Pressure | dp4_nominal | Pressure [Pa] | |
Dynamics | |||
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material |
Nominal condition | |||
Time | tau1 | VTubSeg*rho1_nominal/m1_flow... | Time constant at nominal flow [s] |
Time | tau2 | VTubSeg*rho2_nominal/m2_flow... | Time constant at nominal flow [s] |
Time | tau3 | VTubSeg*rho3_nominal/m3_flow... | Time constant at nominal flow [s] |
Time | tau4 | VTubSeg*rho4_nominal/m4_flow... | Time constant at nominal flow [s] |
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Formulation of energy balance |
Initialization | |||
Temperature | TFlu_start | Start value of fluid temperature [K] | |
Temperature | TGro_start | Start value of grout temperature [K] | |
Medium 1 | |||
AbsolutePressure | p1_start | Medium1.p_default | Start value of pressure [Pa] |
Temperature | T1_start | TFlu_start | Start value of temperature [K] |
MassFraction | X1_start[Medium1.nX] | Medium1.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C1_start[Medium1.nC] | fill(0, Medium1.nC) | Start value of trace substances |
ExtraProperty | C1_nominal[Medium1.nC] | fill(1E-2, Medium1.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Medium 2 | |||
AbsolutePressure | p2_start | Medium2.p_default | Start value of pressure [Pa] |
Temperature | T2_start | TFlu_start | Start value of temperature [K] |
MassFraction | X2_start[Medium2.nX] | Medium2.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C2_start[Medium2.nC] | fill(0, Medium2.nC) | Start value of trace substances |
ExtraProperty | C2_nominal[Medium2.nC] | fill(1E-2, Medium2.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Medium 3 | |||
AbsolutePressure | p3_start | Medium3.p_default | Start value of pressure [Pa] |
Temperature | T3_start | TFlu_start | Start value of temperature [K] |
MassFraction | X3_start[Medium3.nX] | Medium3.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C3_start[Medium3.nC] | fill(0, Medium3.nC) | Start value of trace substances |
ExtraProperty | C3_nominal[Medium3.nC] | fill(1E-2, Medium3.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Medium 4 | |||
AbsolutePressure | p4_start | Medium4.p_default | Start value of pressure [Pa] |
Temperature | T4_start | TFlu_start | Start value of temperature [K] |
MassFraction | X4_start[Medium4.nX] | Medium4.X_default | Start value of mass fractions m_i/m [kg/kg] |
ExtraProperty | C4_start[Medium4.nC] | fill(0, Medium4.nC) | Start value of trace substances |
ExtraProperty | C4_nominal[Medium4.nC] | fill(1E-2, Medium4.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
Assumptions | |||
Boolean | allowFlowReversal1 | true | = true to allow flow reversal in medium 1, false restricts to design direction (port_a -> port_b) |
Boolean | allowFlowReversal2 | true | = true to allow flow reversal in medium 2, false restricts to design direction (port_a -> port_b) |
Boolean | allowFlowReversal3 | true | = true to allow flow reversal in medium 3, false restricts to design direction (port_a -> port_b) |
Boolean | allowFlowReversal4 | true | = true to allow flow reversal in medium 4, false restricts to design direction (port_a -> port_b) |
Advanced | |||
MassFlowRate | m1_flow_small | 1E-4*abs(m1_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
MassFlowRate | m2_flow_small | 1E-4*abs(m2_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
MassFlowRate | m3_flow_small | 1E-4*abs(m3_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
MassFlowRate | m4_flow_small | 1E-4*abs(m4_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
Diagnostics | |||
Boolean | show_T | false | = true, if actual temperature at port is computed |
Flow resistance | |||
Medium 1 | |||
Boolean | from_dp1 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance1 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM1 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Medium 2 | |||
Boolean | from_dp2 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance2 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM2 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Medium 3 | |||
Boolean | from_dp3 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance3 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM3 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Medium 4 | |||
Boolean | from_dp4 | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance4 | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM4 | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Connectors
Type | Name | Description |
---|---|---|
HeatPort_a | port_wall | Thermal connection for borehole wall |
replaceable package Medium1 | Medium 1 in the component | |
replaceable package Medium2 | Medium 2 in the component | |
replaceable package Medium3 | Medium 3 in the component | |
replaceable package Medium4 | Medium 4 in the component | |
FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) |
FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) |
FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) |
FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) |
FluidPort_a | port_a3 | Fluid connector a1 (positive design flow direction is from port_a3 to port_b3) |
FluidPort_b | port_b3 | Fluid connector b2 (positive design flow direction is from port_a3 to port_b3) |
FluidPort_a | port_a4 | Fluid connector a1 (positive design flow direction is from port_a4 to port_b4) |
FluidPort_b | port_b4 | Fluid connector b2 (positive design flow direction is from port_a4 to port_b4) |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.InternalResistancesOneUTube
Internal resistance model for single U-tube borehole segments.
Information
This model simulates the internal thermal resistance network of a borehole segment in the case of a single U-tube borehole using the method of Bauer et al. (2011) and computing explicitely the fluid-to-ground thermal resistance Rb and the grout-to-grout resistance Ra as defined by Claesson and Hellstrom (2011) using the multipole method.
References
J. Claesson and G. Hellstrom. Multipole method to calculate borehole thermal resistances in a borehole heat exchanger. HVAC&R Research, 17(6): 895-911, 2011.
D. Bauer, W. Heidemann, H. Müller-Steinhagen, and H.-J. G. Diersch. Thermal resistance and capacity models for borehole heat exchangers . International Journal Of Energy Research, 35:312-320, 2011.
Extends from Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalResistances (Partial model to implement borehole segment internal resistance models).
Parameters
Type | Name | Default | Description |
---|---|---|---|
Length | hSeg | Length of the internal heat exchanger [m] | |
Temperature | T_start | Initial temperature of the filling material [K] | |
Template | borFieDat | Borefield data | |
ThermalResistance | Rgb_val | Thermal resistance between grout zone and borehole wall [K/W] | |
ThermalResistance | RCondGro_val | Thermal resistance between: pipe wall to capacity in grout [K/W] | |
ThermalResistance | Rgg_val | Thermal resistance between the two grout zones [K/W] | |
HeatCapacity | Co_fil | borFieDat.filDat.dFil*borFie... | Heat capacity of the whole filling material [J/K] |
Dynamics | |||
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state |
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material. |
Connectors
Type | Name | Description |
---|---|---|
HeatPort_a | port_1 | Thermal connection for pipe 1 |
HeatPort_a | port_wall | Thermal connection for pipe 2 |
HeatPort_a | port_2 | Thermal connection for borehole wall |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.InternalResistancesTwoUTube
Internal resistance model for double U-tube borehole segments.
Information
This model simulates the internal thermal resistance network of a borehole segment in the case of a double U-tube borehole using the method of Bauer et al. (2011) and computing explicitely the fluid-to-ground thermal resistance Rb and the grout-to-grout resistance Ra as defined by Claesson and Hellstrom (2011) using the multipole method.
References
J. Claesson and G. Hellstrom. Multipole method to calculate borehole thermal resistances in a borehole heat exchanger. HVAC&R Research, 17(6): 895-911, 2011.
D. Bauer, W. Heidemann, H. Müller-Steinhagen, and H.-J. G. Diersch. Thermal resistance and capacity models for borehole heat exchangers . International Journal Of Energy Research, 35:312-320, 2011.
Extends from Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalResistances (Partial model to implement borehole segment internal resistance models).
Parameters
Type | Name | Default | Description |
---|---|---|---|
Length | hSeg | Length of the internal heat exchanger [m] | |
Temperature | T_start | Initial temperature of the filling material [K] | |
Template | borFieDat | Borefield data | |
ThermalResistance | Rgb_val | Thermal resistance between grout zone and borehole wall [K/W] | |
ThermalResistance | RCondGro_val | Thermal resistance between: pipe wall to capacity in grout [K/W] | |
ThermalResistance | Rgg1_val | Thermal resistance between two neightbouring grout capacities, as defined by Bauer et al (2010) [K/W] | |
ThermalResistance | Rgg2_val | Thermal resistance between two grout capacities opposite to each other, as defined by Bauer et al (2010) [K/W] | |
HeatCapacity | Co_fil | borFieDat.filDat.dFil*borFie... | Heat capacity of the whole filling material [J/K] |
Dynamics | |||
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state |
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material. |
Connectors
Type | Name | Description |
---|---|---|
HeatPort_a | port_1 | Thermal connection for pipe 1 |
HeatPort_a | port_wall | Thermal connection for pipe 2 |
HeatPort_a | port_2 | Thermal connection for borehole wall |
HeatPort_a | port_3 | Thermal connection for borehole wall |
HeatPort_a | port_4 | Thermal connection for borehole wall |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialBorehole
Partial model to implement multi-segment boreholes
Information
Partial model to implement models simulating geothermal U-tube boreholes modeled as several borehole segments, with a uniform borehole wall boundary condition.
Extends from Buildings.Fluid.Interfaces.PartialTwoPortInterface (Partial model with two ports and declaration of quantities that are used by many models), Buildings.Fluid.Interfaces.TwoPortFlowResistanceParameters (Parameters for flow resistance for models with two ports).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Integer | nSeg | 10 | Number of segments to use in vertical discretization of the boreholes |
Template | borFieDat | Borefield parameters | |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate [kg/s] | |
PressureDifference | dp_nominal | Pressure difference [Pa] | |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*abs(m_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
Diagnostics | |||
Boolean | show_T | false | = true, if actual temperature at port is computed |
Flow resistance | |||
Boolean | computeFlowResistance | dp_nominal > Modelica.Consta... | =true, compute flow resistance. Set to false to assume no friction |
Boolean | from_dp | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
Boolean | linearizeFlowResistance | false | = true, use linear relation between m_flow and dp for any flow rate |
Real | deltaM | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
Initialization | |||
Temperature | TGro_start[nSeg] | Start value of grout temperature [K] | |
Temperature | TFlu_start[nSeg] | TGro_start | Start value of fluid temperature [K] |
AbsolutePressure | p_start | Medium.p_default | Start value of pressure [Pa] |
Dynamics | |||
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state |
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
replaceable package Medium | Medium in the component | |
HeatPort_a | port_wall[nSeg] | Thermal connection for borehole wall |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalHEX
Partial model to implement the internal heat exchanger of a borehole segment
Information
Partial model to implement models simulating the thermal and fluid behaviour of a borehole segment.
The thermodynamic properties of the fluid circulating in the borehole are calculated
as protected parameters in this partial model: cp (cpMed
),
k (kMed
) and μ (muMed
). Additionally, the
following parameters are already declared as protected parameters and thus do not
need to be declared in models which extend this partial model:
-
Rgb_val
(Thermal resistance between grout zone and borehole wall) -
RCondGro_val
(Thermal resistance between pipe wall and capacity in grout) -
x
(Grout capacity location)
Parameters
Type | Name | Default | Description |
---|---|---|---|
Template | borFieDat | Borefield parameters | |
replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium | |
Length | hSeg | Length of the internal heat exchanger [m] | |
Volume | VTubSeg | hSeg*Modelica.Constants.pi*(... | Fluid volume in each tube [m3] |
Dynamics | |||
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material |
Initialization | |||
Temperature | TFlu_start | Start value of fluid temperature [K] | |
Temperature | TGro_start | Start value of grout temperature [K] |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium | |
HeatPort_a | port_wall | Thermal connection for borehole wall |
Modelica definition
Buildings.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.PartialInternalResistances
Partial model to implement borehole segment internal resistance models
Information
Partial model to implement the inner resistance network of a borehole segment.
The partial model uses a thermal port representing a uniform borehole wall for that segment, and at least two other thermal ports (one for each tube going through the borehole segment).
Parameters
Type | Name | Default | Description |
---|---|---|---|
Length | hSeg | Length of the internal heat exchanger [m] | |
Temperature | T_start | Initial temperature of the filling material [K] | |
Template | borFieDat | Borefield data | |
ThermalResistance | Rgb_val | Thermal resistance between grout zone and borehole wall [K/W] | |
ThermalResistance | RCondGro_val | Thermal resistance between: pipe wall to capacity in grout [K/W] | |
Dynamics | |||
Conservation equations | |||
Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state |
Boolean | dynFil | true | Set to false to remove the dynamics of the filling material. |
Connectors
Type | Name | Description |
---|---|---|
HeatPort_a | port_1 | Thermal connection for pipe 1 |
HeatPort_a | port_wall | Thermal connection for pipe 2 |
HeatPort_a | port_2 | Thermal connection for borehole wall |