dragonfly_energy.des.ghe module

Ground Heat Exchanger (GHE) in a district thermal system.

class dragonfly_energy.des.ghe.BoreholeParameter(min_depth=60, max_depth=135, min_spacing=3, max_spacing=10, buried_depth=2, diameter=0.15)[source]

Bases: object

Represents the borehole properties within a ground heat exchanger field.

Parameters

  • min_depth – A number for the minimum depth of the heat-exchanging part of the boreholes in meters. All boreholes will have a depth of at least this value. So this typically represents the depth at which borehole-drilling is most economical or the point at which it becomes more cost effective to start a new borehole instead of making a given borehole deeper. (Default: 60).

  • max_depth – A number for the maximum depth of the heat-exchanging part of the boreholes in meters. When the system demand cannot be met using boreholes with the min_depth, the boreholes will be extended until either the loads or met or they reach this depth. So this typically represents the depth of bedrock or the point at which drilling deeper ceases to be practical. (Default: 135).

  • min_spacing – A number for the minimum spacing between boreholes in meters. When the system demand cannot be met using boreholes with the max_spacing, the borehole spacing will be reduced until either the loads or met or they reach this spacing. So this typically represents the spacing at which each borehole will interfere with neighboring ones so much that it is not worthwhile to decrease the spacing further. (Default: 3).

  • max_spacing – A number for the maximum spacing between boreholes in meters. All boreholes will have a spacing of at most this value. So this typically represents the spacing at which the performance effects of one borehole on a neighboring one are negligible. (Default: 10).

  • buried_depth – A number for the depth below the ground surface at which the top of the heat exchanging part of the borehole sits in meters. (Default: 2).

  • diameter – A number for the diameter of the borehole in meters. (Default: 0.15).

Properties:

  • min_depth

  • max_depth

  • min_spacing

  • max_spacing

  • buried_depth

  • diameter

ToString()[source]

Overwrite .NET ToString method.

duplicate()[source]

Get a copy of this object.

classmethod from_dict(data)[source]

Create a BoreholeParameter object from a dictionary

Parameters

data – A dictionary representation of an BoreholeParameter object in the format below.

{
'type': 'BoreholeParameter',
'min_depth': 30,  # float in meters
'max_depth': 90,  # float in meters
'min_spacing': 2.5,  # float in meters
'max_spacing': 8,  # float in meters
'buried_depth': 4,  # float in meters
'diameter': 0.2  # float in meters
}
to_dict()[source]

Get BoreholeParameter dictionary.

property buried_depth

Get or set a number for the depth of the top of the borehole in meters.

property diameter

Get or set a number for the diameter of the borehole in meters.

property max_depth

Get or set a number number for the maximum depth of the borehole in meters.

property max_spacing

Get or set a number number for the maximum spacing between boreholes in m.

property min_depth

Get or set a number number for the minimum depth of the borehole in meters.

property min_spacing

Get or set a number number for the minimum spacing between boreholes in m.

class dragonfly_energy.des.ghe.FluidParameter(fluid_type='Water', concentration=35, temperature=20)[source]

Bases: object

Represents the fluid properties within a ground heat exchanger field.

Parameters

  • fluid_type –

    Text to indicate the type of fluid circulating through the ground heat exchanger loop. Choose from the options below. (Default: Water).

    • Water

    • EthylAlcohol

    • EthyleneGlycol

    • MethylAlcohol

    • PropyleneGlycol

  • concentration – A number between 0 and 60 for the concentration of the fluid_type in water in percent. Note that this variable has no effect when the fluid_type is Water. (Default: 35).

  • temperature – A number for the average design fluid temperature at peak conditions in Celsius. (Default: 20).

Properties:

  • fluid_type

  • concentration

  • temperature

ToString()[source]

Overwrite .NET ToString method.

duplicate()[source]

Get a copy of this object.

classmethod from_dict(data)[source]

Create a FluidParameter object from a dictionary

Parameters

data – A dictionary representation of an FluidParameter object in the format below.

{
'type': 'FluidParameter',
'fluid_type': 'PropyleneGlycol',  # text for fluid_type
'concentration': 33,  # float for percentage concentration
'temperature': 22  # float in C
}
to_dict()[source]

Get FluidParameter dictionary.

FLUID_TYPES = ('Water', 'EthylAlcohol', 'EthyleneGlycol', 'MethylAlcohol', 'PropyleneGlycol')
property concentration

Get or set a number for the concentration of the fluid_type in water [%].

property fluid_type

Get or set text to indicate the type of fluid.

property temperature

Get or set a number for the average design fluid temperature in Celsius.

class dragonfly_energy.des.ghe.GroundHeatExchanger(identifier, geometry)[source]

Bases: _GeometryBase

Represents a Ground Heat Exchanger in a district thermal system.

Parameters

  • identifier – Text string for a unique heat exchanger ID. Must contain only characters that are acceptable in OpenDSS. This will be used to identify the object across the exported geoJSON and OpenDSS files.

  • geometry – A Polygon2D representing the geometry of the heat exchanger.

Properties:

  • identifier

  • display_name

  • geometry

ToString()
duplicate()

Get a copy of this object.

classmethod from_dict(data)[source]

Initialize a GroundHeatExchanger from a dictionary.

Parameters

data – A dictionary representation of an GroundHeatExchanger object.

classmethod from_geojson_dict(data, origin_lon_lat, conversion_factors)[source]

Get a GroundHeatExchanger from a dictionary as it appears in a GeoJSON.

Parameters

  • data – A GeoJSON dictionary representation of an GroundHeatExchanger feature.

  • origin_lon_lat – An array of two numbers in degrees. The first value represents the longitude of the scene origin in degrees (between -180 and +180). The second value represents latitude of the scene origin in degrees (between -90 and +90). Note that the “scene origin” is the (0, 0) coordinate in the 2D space of the input polygon.

  • conversion_factors – A tuple with two values used to translate between meters and longitude, latitude.

move(moving_vec)

Move this object along a vector.

Parameters

moving_vec – A ladybug_geometry Vector3D with the direction and distance to move the object.

reflect(plane)

Reflect this object across a plane.

Parameters

plane – A ladybug_geometry Plane across which the object will be reflected.

rotate_xy(angle, origin)

Rotate this object counterclockwise in the XY plane by a certain angle.

Parameters

  • angle – An angle in degrees.

  • origin – A ladybug_geometry Point3D for the origin around which the object will be rotated.

scale(factor, origin=None)

Scale this object by a factor from an origin point.

Parameters

  • factor – A number representing how much the object should be scaled.

  • origin – A ladybug_geometry Point3D representing the origin from which to scale. If None, it will be scaled from the World origin (0, 0, 0).

to_dict()[source]

GroundHeatExchanger dictionary representation.

to_geojson_dict(origin_lon_lat, conversion_factors)[source]

Get GroundHeatExchanger dictionary as it appears in an URBANopt geoJSON.

Parameters

  • origin_lon_lat – An array of two numbers in degrees. The first value represents the longitude of the scene origin in degrees (between -180 and +180). The second value represents latitude of the scene origin in degrees (between -90 and +90). Note that the “scene origin” is the (0, 0) coordinate in the 2D space of the input polygon.

  • conversion_factors – A tuple with two values used to translate between meters and longitude, latitude.

property display_name

Get or set a string for the object name without any character restrictions.

If not set, this will be equal to the identifier.

property geometry

Get a Polygon2D representing the ground heat exchanger.

property identifier

Get or set the text string for unique object identifier.

class dragonfly_energy.des.ghe.PipeParameter(inner_diameter=0.0216, outer_diameter=0.0266, shank_spacing=0.0323, roughness=1e-06, conductivity=0.4, heat_capacity=1542000)[source]

Bases: object

Represents the pipe properties within a ground heat exchanger field.

Parameters

  • inner_diameter – A number for the diameter of the inner pipe surface in meters. (Default: 0.0216).

  • outer_diameter – A number for the diameter of the outer pipe surface in meters. (Default: 0.0266).

  • shank_spacing – A number for the spacing between the U-tube legs, as referenced from outer surface of the pipes in meters. (NOT referenced from each pipe’s respective centerline). (Default: 0.0323).

  • roughness – A number for the linear dimension of bumps on the pipe surface in meters. (Default: 1e-06)

  • conductivity – A number for the conductivity of the pipe material in W/m-K. (Default: 0.4).

  • heat_capacity – A number for the volumetric heat capacity of the pipe material in J/m3-K. (Default: 1,542,000).

Properties:

  • inner_diameter

  • outer_diameter

  • shank_spacing

  • roughness

  • conductivity

  • heat_capacity

ToString()[source]

Overwrite .NET ToString method.

duplicate()[source]

Get a copy of this object.

classmethod from_dict(data)[source]

Create a PipeParameter object from a dictionary

Parameters

data – A dictionary representation of an PipeParameter object in the format below.

{
'type': 'PipeParameter',
'inner_diameter': 0.0216,  # float for inner diameter in meters
'outer_diameter': 0.0266  # float for outer diameter in meters
'shank_spacing': 0.0323,  # float for spacing between outer pipes in meters
'roughness': 1e-06,  # float for the dimension of the surface bumps
'conductivity': 0.6,  # float in W/m2-K
'heat_capacity': 1542000  # float in J/m3-K
}
to_dict()[source]

Get PipeParameter dictionary.

property conductivity

Get or set a number for the conductivity of the pipe material in W/m-K.

property heat_capacity

Get or set a number for the volumetric heat capacity of the pipe in J/m3-K.

property inner_diameter

Get or set a number for the inner diameter of the pipe in meters.

property outer_diameter

Get or set a number for the outer diameter of the pipe in meters.

property roughness

Get or set a number for the dimension of the pipe surface bumps in meters.

property shank_spacing

Get or set a number for the shank spacing between the pipes in meters.

class dragonfly_energy.des.ghe.SoilParameter(conductivity=2.3, heat_capacity=2343500, undisturbed_temperature=Autocalculate)[source]

Bases: object

Represents the soil properties within a ground heat exchanger field.

Parameters

  • conductivity – A number for the soil conductivity in W/m-K. (Default: 2.3).

  • heat_capacity – A number for the volumetric heat capacity of the soil in J/m3-K. (Default: 2,343,500).

  • undisturbed_temperature – A number for the undisturbed annual average soil temperature in degrees Celsius. If autocalculate, this value will automatically be replaced with the average EPW temperature before simulation. (Default: Autocalculate).

Properties:

  • conductivity

  • heat_capacity

  • undisturbed_temperature

ToString()[source]

Overwrite .NET ToString method.

duplicate()[source]

Get a copy of this object.

classmethod from_dict(data)[source]

Create a SoilParameter object from a dictionary

Parameters

data – A dictionary representation of an SoilParameter object in the format below.

{
'type': 'SoilParameter',
'conductivity': 1.8,  # float in W/m2-K
'heat_capacity': 2100000,  # float in J/m3-K
'undisturbed_temperature': 18  # float in C or autocalculate
}
to_dict()[source]

Get SoilParameter dictionary.

property conductivity

Get or set a number for the soil conductivity in W/m-K.

property heat_capacity

Get or set a number for the volumetric heat capacity of the soil in J/m3-K.

property undisturbed_temperature

Get or set an integer (or Autocalculate) for the vegetation end month.