def test_finite_line_source_image_part(self, rel_tol=1.0e-6):
""" Tests the value of the image part of the FLS solution.
"""
from pygfunction.boreholes import Borehole
from pygfunction.heat_transfer import finite_line_source
# Evaluate the double integral
reference = dblquad(
fls_double,
self.D1,
self.D1 + self.H1,
lambda x: self.D2,
lambda x: self.D2 + self.H2,
args=(self.t, self.dis, self.alpha, False, True))[0] / self.H2
# Evaluate using heat_transfer.finite_line_source
borehole1 = Borehole(self.H1, self.D1, 0.05, 0., 0.)
borehole2 = Borehole(self.H2, self.D2, 0.05, self.dis, 0.)
calculated = finite_line_source(self.t,
self.alpha,
borehole1,
borehole2,
reaSource=False,
imgSource=True)
self.assertAlmostEqual(calculated,
reference,
delta=np.abs(rel_tol * reference),
msg='Incorrect value of the image part of the '
'finite line source solution.')
def test_two_unequal_boreholes_four_segments(self, rel_tol=1.0e-6):
""" Tests the value of the thermal response factor matrix for two
boreholes of unequal lengths with and without similarities.
"""
from pygfunction.heat_transfer import thermal_response_factors
from pygfunction.gfunction import _borehole_segments
from pygfunction.boreholes import Borehole
borehole1 = Borehole(self.H, self.D, self.r_b, 0., 0.)
borehole2 = Borehole(self.H * 1.432, self.D, self.r_b, self.B, 0.)
boreField = [borehole1, borehole2]
boreSegments = _borehole_segments(boreField, nSegments=4)
time = np.array([33554478]) * 3600.
# Calculation of thermal response factor matrix using similarities
h = thermal_response_factors(boreSegments,
time,
self.alpha,
use_similarities=True)
# Calculation of thermal response factor matrix without similarities
h_none = thermal_response_factors(boreSegments,
time,
self.alpha,
use_similarities=False)
self.assertTrue(np.allclose(h, h_none, rtol=rel_tol, atol=1e-10),
msg='Incorrect values of the thermal response factors '
'two unequal boreholes (4 segments).')
def test_finite_line_source_no_part(self, rel_tol=1.0e-6):
""" Tests the value of the FLS solution when considering no source.
"""
from pygfunction.boreholes import Borehole
from pygfunction.heat_transfer import finite_line_source
# Evaluate using heat_transfer.finite_line_source
borehole1 = Borehole(self.H1, self.D1, 0.05, 0., 0.)
borehole2 = Borehole(self.H2, self.D2, 0.05, self.dis, 0.)
calculated = finite_line_source(self.t, self.alpha,
borehole1, borehole2,
reaSource=False, imgSource=False)
self.assertEqual(calculated, 0.,
msg='Incorrect value of no part of the '
'finite line source solution.')
def test_fluid_heat_transfer_rate_series(self):
""" Tests the value of the fluid heat transfer rate for a borehole with
multiple U-tubes in series.
"""
from pygfunction.pipes import MultipleUTube
from pygfunction.boreholes import Borehole
# Reference solution (Cimmino, 2016)
nPipes = [2, 3, 4] # Number of U-tubes
# Fluid mass flow rate [kg/s]
m_flow = 0.3
T_b = 1.0 # Borehole wall temperature [degC]
# Outlet fluid temperature [degC]
Tf_out = np.array([1.6215, 1.2051, 1.1065])
# Inlet fluid temperature [degC]
Tf_in = np.array([5.0, 5.0, 5.0])
# Total heat transfer rate [W]
Qf_ref = m_flow*self.cp*(Tf_out - Tf_in)
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
# Calculate using pipes.MultipleUTube()
Qf = np.zeros_like(Qf_ref)
for i in range(len(nPipes)):
pos = self._pipePositions(nPipes[i])
UTube = MultipleUTube(pos, 0., self.r_out, borehole,
self.k_s, self.k_g, self.Rfp, nPipes[i],
config='series', J=0)
# Obtain fluid heat extraction rate
Qf[i] = UTube.get_fluid_heat_extraction_rate(Tf_in[i], T_b,
m_flow, self.cp)
self.assertTrue(np.allclose(Qf, Qf_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of fluid heat extraction rate '
'for U-tubes in series.')
def test_inlet_fluid_temperature_parallel(self):
""" Tests the value of the inlet fluid temperature for a borehole with
multiple U-tubes in parallel.
"""
from pygfunction.pipes import MultipleUTube
from pygfunction.boreholes import Borehole
# Reference solution (Cimmino, 2016)
nPipes = [2, 3, 4] # Number of U-tubes
# Fluid mass flow rate [kg/s]
m_flow = np.array([0.2*n for n in nPipes])
T_b = 1.0 # Borehole wall temperature [degC]
# Outlet fluid temperature [degC]
Tf_out = np.array([2.0860, 2.2279, 2.4627])
# Inlet fluid temperature [degC]
Tf_in_ref = np.array([5.0, 5.0, 5.0])
# Total heat transfer rate [W]
Qf = m_flow*self.cp*(Tf_out - Tf_in_ref)
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
# Calculate using pipes.MultipleUTube()
Tf_in = np.zeros_like(Tf_in_ref)
for i in range(len(nPipes)):
pos = self._pipePositions(nPipes[i])
UTube = MultipleUTube(pos, 0., self.r_out, borehole,
self.k_s, self.k_g, self.Rfp, nPipes[i], J=0)
# Obtain inlet fluid temperature
Tf_in[i] = UTube.get_inlet_temperature(Qf[i], T_b,
m_flow[i], self.cp)
self.assertTrue(np.allclose(Tf_in, Tf_in_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of inlet fluid temperatures for '
'U-tubes in parallel.')
def test_outlet_fluid_temperature_series(self):
""" Tests the value of the outlet fluid temperature for a borehole with
multiple U-tubes in series.
"""
from pygfunction.pipes import MultipleUTube
from pygfunction.boreholes import Borehole
# Reference solution (Cimmino, 2016)
nPipes = [2, 3, 4] # Number of U-tubes
# Fluid mass flow rate [kg/s]
m_flow = 0.3
T_b = 1.0 # Borehole wall temperature [degC]
Tf_in = 5.0 # Inlet fluid temperature [degC]
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
Tf_out_ref = np.array([1.6215, 1.2051, 1.1065])
# Calculate using pipes.MultipleUTube()
Tf_out = np.zeros_like(Tf_out_ref)
for i in range(len(nPipes)):
pos = self._pipePositions(nPipes[i])
UTube = MultipleUTube(pos, 0., self.r_out, borehole,
self.k_s, self.k_g, self.Rfp, nPipes[i],
config='series', J=0)
# Obtain outlet fluid temperature
Tf_out[i] = UTube.get_outlet_temperature(Tf_in, T_b,
m_flow, self.cp)
self.assertTrue(np.allclose(Tf_out, Tf_out_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of outlet fluid temperatures for '
'U-tubes in series.')
def test_fluid_heat_transfer_rate(self):
""" Tests the value of the fluid heat transfer rate for a single U-tube
borehole.
"""
from pygfunction.pipes import SingleUTube
from pygfunction.boreholes import Borehole
# Reference solution (Cimmino, 2016)
# Fluid mass flow rate [kg/s]
m_flow = np.array([0.2, 0.3])
T_b = 1.0 # Borehole wall temperature [degC]
# Outlet fluid temperature [degC]
Tf_out = np.array([2.2161, 2.8394])
# Inlet fluid temperature [degC]
Tf_in = np.array([5.0, 5.0])
# Total heat transfer rate [W]
Qf_ref = m_flow*self.cp*(Tf_out - Tf_in)
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
# Calculate using pipes.SingleUTube()
Qf = np.zeros_like(Qf_ref)
for i in range(len(m_flow)):
pos = [(-self.D_s, 0.), (self.D_s, 0.)]
UTube = SingleUTube(pos, 0., self.r_out, borehole,
self.k_s, self.k_g, self.Rfp, J=0)
# Obtain fluid heat transfer rate
Qf[i] = UTube.get_fluid_heat_extraction_rate(Tf_in[i], T_b,
m_flow[i], self.cp)
self.assertTrue(np.allclose(Qf, Qf_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of fluid heat extraction rate.')
def test_outlet_fluid_temperature(self):
""" Tests the value of the outlet fluid temperature for a single U-tube
borehole.
"""
from pygfunction.pipes import SingleUTube
from pygfunction.boreholes import Borehole
# Reference solution (Cimmino, 2016)
# Fluid mass flow rate [kg/s]
m_flow = np.array([0.2, 0.3])
T_b = 1.0 # Borehole wall temperature [degC]
Tf_in = 5.0 # Inlet fluid temperature [degC]
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
Tf_out_ref = np.array([2.2161, 2.8394])
# Calculate using pipes.SingleUTube()
Tf_out = np.zeros_like(Tf_out_ref)
for i in range(len(m_flow)):
pos = [(-self.D_s, 0.), (self.D_s, 0.)]
UTube = SingleUTube(pos, 0., self.r_out, borehole,
self.k_s, self.k_g, self.Rfp, J=0)
# Obtain outlet fluid temperature
Tf_out[i] = UTube.get_outlet_temperature(Tf_in, T_b,
m_flow[i], self.cp)
self.assertTrue(np.allclose(Tf_out, Tf_out_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of outlet fluid temperatures.')
def test_fluid_heat_transfer_rate(self):
""" Tests the value of the fluid heat transfer rates for a borehole
with multiple independent U-tubes.
"""
from pygfunction.pipes import IndependentMultipleUTube
from pygfunction.boreholes import Borehole
borehole = Borehole(self.H, 0., self.r_b, 0., 0.)
# Calculate using pipes.IndependentMultipleUTube()
pos = self._pipePositions(self.nPipes)
UTube = IndependentMultipleUTube(pos,
1e-30,
self.r_out,
borehole,
self.k_s,
self.k_g,
self.Rfp,
self.nPipes,
J=0)
# Obtain outlet fluid temperature
Qf = UTube.get_fluid_heat_extraction_rate(self.Tf_in_ref, self.T_b,
self.m_flow, self.cp)
self.assertTrue(np.allclose(Qf, self.Qf_ref, rtol=1e-4, atol=1e-10),
msg='Incorrect value of fluid heat extraction rates '
'for independent U-tubes.')
