Grout Material¶
-
class
pygld.
GroutMaterial
(kth=None, Cp=None)[source]¶ The
GroutMaterial
class holds all the thermophysical properties relative to the grout that are required for the modeling of ground-loop heat exchanger systems.A database of predefined grout materials is available and can be obtained or printed with the
get_predefined_materials()
andprint_predefined_materials()
methods. TheGroutMaterial
can be initialized directly from a predefined material with theinit_as()
, passing as argument the index of the material in the database.An Example is available at the end of this section.
Thermal Properties¶
-
GroutMaterial.
Cp
¶ Volumetric heat capacity in J/m³·K.
Get or set the volumetric heat capacity of the material as a single positive float value.
-
GroutMaterial.
kth
¶ Thermal conductivity in W/m·K.
Get or set the thermal conductivity of the material as a single positive float value.
-
GroutMaterial.
al
¶ Thermal diffusivity in m²/s.
Return the thermal diffusivity of the material as a single positive float value calculated as:
where is the thermal conductivity in W/m·k and is the volumetric heat capacity of the material in J/m³·K.
Utilities¶
-
classmethod
GroutMaterial.
get_predefined_materials
()¶ Return a dict containing the predefined
GroutMaterial
.
-
classmethod
GroutMaterial.
print_predefined_materials
(end='\n')¶ Print all the predefined
GroutMaterial
.
-
classmethod
GroutMaterial.
init_as
(material_index)¶ Initialize the thermal properties of the
GroutMaterial
based on the specified material index.This is a convenience function; the member variables can also be initialized manually.
Example¶
Import and print the list of predefined GroutMaterial
:
>>> from pygld import GroundMaterial
>>> GroundMaterial.print_predefined_materials()
Predefined materials for the 'Grout':
0 - Bentonite 12% ........ kth=0.700 W/m·k, Cp=3900 J/m³·K
1 - Bentonite/Sand 12%/15% kth=1.500 W/m·k, Cp=3400 J/m³·K
2 - Water ................ kth=0.600 W/m·k, Cp=4200 J/m³·K
Initialize GroutMaterial
from the predefined material at index
#1 and print the results:
>>> grout = GroundMaterial.init_as(1)
>>> print(grout)
Grout material: Bentonite/Sand 12%/15%
Thermal conductivity: 1.500 W/m·k
Volumetric heat capacity: 3400 J/m³·K
Thermal diffusivity: 4.41e-04 m²/s
Change the thermal conductivity for another value and print the results:
>>> grout.kth = 1.75
>>> print(grout)
Grout material: User Defined
Thermal conductivity: 1.750 W/m·k
Volumetric heat capacity: 3400 J/m³·K
Thermal diffusivity: 5.15e-04 m²/s
Note that the grout material is now labeled as ‘User defined’.
It is also possible to initialize an empty GroutMaterial
and
set the value of the properties manually:
>>> grout = GroutMaterial()
>>> grout.kth = 2
>>> grout.Cp = 3500
>>> print(grout)
Grout material: User Defined
Thermal conductivity: 2.000 W/m·k
Volumetric heat capacity: 3500 J/m³·K
Thermal diffusivity: 5.71e-04 m²/s