Note
Click here to download the full example code
Fluent setup and solution using settings objects#
This example sets up and solves a three-dimensional turbulent fluid flow and heat transfer problem in a mixing elbow, which is common in piping systems in power plants and process industries. Predicting the flow field and temperature field in the area of the mixing region is important to designing the junction properly.
This example uses settings objects.
Problem description
A cold fluid at 20 deg C flows into the pipe through a large inlet. It then mixes
with a warmer fluid at 40 deg C that enters through a smaller inlet located at
the elbow. The pipe dimensions are in inches, and the fluid properties and
boundary conditions are given in SI units. Because the Reynolds number for the
flow at the larger inlet is 50, 800, a turbulent flow model is required.
Perform required imports#
Perform required imports, which includes downloading and importing the geometry file.
import ansys.fluent.core as pyfluent
from ansys.fluent.core import examples
import_filename = examples.download_file("mixing_elbow.msh.h5", "pyfluent/mixing_elbow")
Launch Fluent#
Launch Fluent as a service in meshing mode with double precision running on two processors.
solver = pyfluent.launch_fluent(precision="double", processor_count=2, mode="solver")
Import mesh and perform mesh check#
Import the mesh and perform a mesh check, which lists the minimum and maximum x, y, and z values from the mesh in the default SI units of meters. The mesh check also reports a number of other mesh features that are checked. Any errors in the mesh are reported. Ensure that the minimum volume is not negative because Fluent cannot begin a calculation when this is the case.
solver.file.read(file_type="case", file_name=import_filename)
solver.tui.mesh.check()
Fast-loading "/ansys_inc/v222/fluent/fluent22.2.0/addons/afd/lib/hdfio.bin"
Done.
Reading from 22a8806ddaee:"/home/ansys/.local/share/ansys_fluent_core/examples/mixing_elbow.msh.h5" in NODE0 mode ...
Reading mesh ...
17587 cells, 1 cell zone ...
17587 mixed cells, zone id: 87
90052 faces, 7 face zones ...
2169 polygonal wall faces, zone id: 34
271 polygonal wall faces, zone id: 33
155 polygonal pressure-outlet faces, zone id: 32
152 polygonal velocity-inlet faces, zone id: 31
54 polygonal velocity-inlet faces, zone id: 30
1993 polygonal symmetry faces, zone id: 29
85258 mixed interior faces, zone id: 89
65225 nodes, 3 node zones ...
Building...
mesh
distributing mesh
parts..,
faces..,
nodes..,
cells..,
bandwidth reduction using Reverse Cuthill-McKee: 8432/280 = 30.1143
materials,
interface,
domains,
zones,
Skipping thread 20 of domain 1 (not referenced by grid).
Skipping thread 21 of domain 1 (not referenced by grid).
Skipping thread 22 of domain 1 (not referenced by grid).
Skipping thread 23 of domain 1 (not referenced by grid).
Skipping thread 24 of domain 1 (not referenced by grid).
Skipping thread 25 of domain 1 (not referenced by grid).
Skipping thread 26 of domain 1 (not referenced by grid).
Skipping thread 27 of domain 1 (not referenced by grid).
Skipping thread 28 of domain 1 (not referenced by grid).
wall-elbow
wall-inlet
outlet
cold-inlet
hot-inlet
symmetry-xyplane
interior--elbow-fluid
elbow-fluid
parallel,
Done.
Mesh is now scaled to meters.
Domain Extents:
x-coordinate: min (m) = -2.000000e-01, max (m) = 2.000000e-01
y-coordinate: min (m) = -2.250000e-01, max (m) = 2.000000e-01
z-coordinate: min (m) = 0.000000e+00, max (m) = 4.994352e-02
Volume statistics:
minimum volume (m3): 2.439339e-10
maximum volume (m3): 5.222798e-07
total volume (m3): 2.500675e-03
Face area statistics:
minimum face area (m2): 3.378535e-08
maximum face area (m2): 7.589314e-05
Checking mesh.....................................
Done.
Set working units for mesh#
Set the working units for the mesh to inches. Because the default SI units are used for everything except length, you do not have to change any other units in this example. If you want working units for length to be other than inches (for example, millimeters), make the appropriate change.
solver.tui.define.units("length", "in")
Enable heat transfer#
Enable heat transfer by activating the energy equation.
solver.setup.models.energy.enabled = True
Create material#
Create a material named "water-liquid".
if solver.get_fluent_version() == "22.2.0":
solver.setup.materials.copy_database_material_by_name(
type="fluid", name="water-liquid"
)
else:
solver.setup.materials.database.copy_by_name(type="fluid", name="water-liquid")
Set up cell zone conditions#
Set up the cell zone conditions for the fluid zone (elbow-fluid). Set material
to "water-liquid".
solver.setup.cell_zone_conditions.fluid["elbow-fluid"].material = "water-liquid"
water-liquid copied from database.
Set up boundary conditions for CFD analysis#
Set up the boundary conditions for the inlets, outlet, and walls for CFD analysis.
# cold inlet (cold-inlet), Setting: Value:
# Velocity Specification Method: Magnitude, Normal to Boundary
# Velocity Magnitude: 0.4 [m/s]
# Specification Method: Intensity and Hydraulic Diameter
# Turbulent Intensity: 5 [%]
# Hydraulic Diameter: 4 [inch]
# Temperature: 293.15 [K]
if solver.get_fluent_version() == "22.2.0":
solver.setup.boundary_conditions.velocity_inlet["cold-inlet"].vmag = {
"option": "constant or expression",
"constant": 0.4,
}
else:
solver.setup.boundary_conditions.velocity_inlet["cold-inlet"].vmag = 0.4
solver.setup.boundary_conditions.velocity_inlet[
"cold-inlet"
].ke_spec = "Intensity and Hydraulic Diameter"
solver.setup.boundary_conditions.velocity_inlet["cold-inlet"].turb_intensity = 0.05
solver.setup.boundary_conditions.velocity_inlet[
"cold-inlet"
].turb_hydraulic_diam = "4 [in]"
if solver.get_fluent_version() == "22.2.0":
solver.setup.boundary_conditions.velocity_inlet["cold-inlet"].t = {
"option": "constant or expression",
"constant": 293.15,
}
else:
solver.setup.boundary_conditions.velocity_inlet["cold-inlet"].t = 293.15
# hot inlet (hot-inlet), Setting: Value:
# Velocity Specification Method: Magnitude, Normal to Boundary
# Velocity Magnitude: 1.2 [m/s]
# Specification Method: Intensity and Hydraulic Diameter
# Turbulent Intensity: 5 [%]
# Hydraulic Diameter: 1 [inch]
# Temperature: 313.15 [K]
if solver.get_fluent_version() == "22.2.0":
solver.setup.boundary_conditions.velocity_inlet["hot-inlet"].vmag = {
"option": "constant or expression",
"constant": 1.2,
}
else:
solver.setup.boundary_conditions.velocity_inlet["hot-inlet"].vmag = 1.2
solver.setup.boundary_conditions.velocity_inlet[
"hot-inlet"
].ke_spec = "Intensity and Hydraulic Diameter"
solver.setup.boundary_conditions.velocity_inlet[
"hot-inlet"
].turb_hydraulic_diam = "1 [in]"
if solver.get_fluent_version() == "22.2.0":
solver.setup.boundary_conditions.velocity_inlet["hot-inlet"].t = {
"option": "constant or expression",
"constant": 313.15,
}
else:
solver.setup.boundary_conditions.velocity_inlet["hot-inlet"].t = 313.15
# pressure outlet (outlet), Setting: Value:
# Backflow Turbulent Intensity: 5 [%]
# Backflow Turbulent Viscosity Ratio: 4
solver.setup.boundary_conditions.pressure_outlet["outlet"].turb_viscosity_ratio = 4
Disable plotting of residuals during calculation#
Disable plotting of residuals during the calculation.
solver.tui.solve.monitors.residual.plot("no")
Initialize flow field#
Initialize the flow field using hybrid initialization.
solver.solution.initialization.hybrid_initialize()
Initialize using the hybrid initialization method.
Checking case topology...
-This case has both inlets & outlets
-Pressure information is not available at the boundaries.
Case will be initialized with constant pressure
iter scalar-0
1 1.000000e+00
2 1.738234e-04
3 1.368013e-05
4 1.375658e-05
5 2.304117e-06
6 2.940066e-06
7 5.519821e-07
8 6.272616e-07
9 1.455065e-07
10 1.523093e-07
Hybrid initialization is done.
Solve for 150 iterations#
Solve for 150 iterations.
solver.solution.run_calculation.iterate.get_attr("arguments")
solver.solution.run_calculation.iterate(number_of_iterations=150)
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
1 1.0000e+00 4.1446e-03 4.5526e-03 1.1641e-03 8.6286e-05 9.8063e-02 7.0256e-01 0:00:36 149
2 7.9759e-01 2.5357e-03 3.0876e-03 7.1473e-04 1.0079e-04 5.5463e-02 1.0028e-01 0:00:40 148
3 7.8389e-01 1.6247e-03 2.3079e-03 6.1399e-04 1.0844e-04 2.0408e-02 6.3198e-02 0:00:39 147
4 7.5152e-01 1.0839e-03 1.9867e-03 5.0024e-04 1.1745e-04 1.7507e-02 3.9559e-02 0:00:38 146
5 7.1958e-01 9.0978e-04 1.8373e-03 4.3477e-04 1.2339e-04 1.6349e-02 2.7030e-02 0:00:37 145
6 6.6453e-01 8.5976e-04 1.7300e-03 3.9692e-04 1.2548e-04 1.6091e-02 2.0521e-02 0:00:36 144
7 6.0323e-01 8.0690e-04 1.6589e-03 3.6579e-04 1.2486e-04 1.6421e-02 1.6988e-02 0:00:36 143
8 5.4631e-01 7.5011e-04 1.5956e-03 3.3743e-04 1.2123e-04 1.7143e-02 1.4379e-02 0:00:35 142
9 4.9671e-01 7.0596e-04 1.5353e-03 3.1504e-04 1.1473e-04 1.7899e-02 1.2379e-02 0:00:34 141
10 4.5876e-01 6.7725e-04 1.4570e-03 2.9619e-04 1.0694e-04 1.8312e-02 1.0634e-02 0:00:34 140
11 4.2320e-01 6.4846e-04 1.3725e-03 2.8035e-04 9.7363e-05 1.8272e-02 9.2497e-03 0:00:33 139
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
12 3.8808e-01 6.1823e-04 1.2832e-03 2.6670e-04 8.6254e-05 1.7764e-02 8.2084e-03 0:00:33 138
13 3.5831e-01 5.8690e-04 1.1923e-03 2.5347e-04 7.4211e-05 1.6845e-02 7.2887e-03 0:00:33 137
14 3.3216e-01 5.5444e-04 1.0919e-03 2.4149e-04 6.3153e-05 1.5574e-02 6.4933e-03 0:00:32 136
15 3.0867e-01 5.2431e-04 9.9411e-04 2.2986e-04 5.3582e-05 1.4094e-02 5.7703e-03 0:00:32 135
16 2.9406e-01 4.9553e-04 9.0080e-04 2.1916e-04 4.6822e-05 1.2544e-02 5.1209e-03 0:00:32 134
17 2.8050e-01 4.6644e-04 8.1350e-04 2.0923e-04 4.2253e-05 1.0987e-02 4.5370e-03 0:00:32 133
18 2.6462e-01 4.3809e-04 7.3875e-04 2.0063e-04 3.9154e-05 9.5339e-03 4.0047e-03 0:00:31 132
19 2.4941e-01 4.0862e-04 6.7224e-04 1.9244e-04 3.6571e-05 8.2102e-03 3.5557e-03 0:00:31 131
20 2.3700e-01 3.7981e-04 6.1669e-04 1.8493e-04 3.3600e-05 7.0115e-03 3.2009e-03 0:00:30 130
21 2.2275e-01 3.5314e-04 5.7142e-04 1.7832e-04 3.0260e-05 5.9645e-03 2.8866e-03 0:00:30 129
22 2.1131e-01 3.2793e-04 5.3440e-04 1.7135e-04 2.6810e-05 5.0689e-03 2.6310e-03 0:00:30 128
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
23 2.0034e-01 3.0411e-04 5.0623e-04 1.6521e-04 2.3411e-05 4.2989e-03 2.3941e-03 0:00:29 127
24 1.9058e-01 2.8212e-04 4.8208e-04 1.5880e-04 2.0381e-05 3.6899e-03 2.1940e-03 0:00:28 126
25 1.8261e-01 2.6147e-04 4.6035e-04 1.5183e-04 1.7681e-05 3.2224e-03 2.0147e-03 0:00:28 125
26 1.7406e-01 2.4231e-04 4.3910e-04 1.4421e-04 1.5228e-05 2.8408e-03 1.8426e-03 0:00:27 124
27 1.6500e-01 2.2462e-04 4.1861e-04 1.3608e-04 1.3094e-05 2.5080e-03 1.6899e-03 0:00:27 123
28 1.5568e-01 2.0807e-04 3.9608e-04 1.2814e-04 1.1310e-05 2.2370e-03 1.5509e-03 0:00:27 122
29 1.4600e-01 1.9236e-04 3.7323e-04 1.2009e-04 9.8144e-06 2.0171e-03 1.4249e-03 0:00:26 121
30 1.3655e-01 1.7753e-04 3.5028e-04 1.1197e-04 8.5374e-06 1.8372e-03 1.3125e-03 0:00:26 120
31 1.2724e-01 1.6354e-04 3.2762e-04 1.0395e-04 7.4371e-06 1.6876e-03 1.2181e-03 0:00:26 119
32 1.1943e-01 1.5052e-04 3.0590e-04 9.6020e-05 6.4981e-06 1.5571e-03 1.1312e-03 0:00:25 118
33 1.1033e-01 1.3803e-04 2.8431e-04 8.8311e-05 5.6967e-06 1.4394e-03 1.0473e-03 0:00:25 117
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
34 1.0218e-01 1.2633e-04 2.6388e-04 8.0998e-05 5.0142e-06 1.3332e-03 9.7072e-04 0:00:25 116
35 9.4471e-02 1.1559e-04 2.4488e-04 7.4179e-05 4.4315e-06 1.2407e-03 9.0354e-04 0:00:25 115
36 8.7537e-02 1.0558e-04 2.2682e-04 6.7838e-05 3.9296e-06 1.1545e-03 8.4070e-04 0:00:24 114
37 8.1099e-02 9.6339e-05 2.0955e-04 6.2021e-05 3.5027e-06 1.0771e-03 7.8149e-04 0:00:24 113
38 7.5269e-02 8.7800e-05 1.9362e-04 5.6702e-05 3.1345e-06 1.0057e-03 7.2542e-04 0:00:24 112
39 6.9832e-02 8.0026e-05 1.7871e-04 5.1839e-05 2.8135e-06 9.4063e-04 6.7326e-04 0:00:24 111
40 6.4683e-02 7.2876e-05 1.6504e-04 4.7383e-05 2.5379e-06 8.8023e-04 6.2415e-04 0:00:23 110
41 6.0100e-02 6.6384e-05 1.5230e-04 4.3332e-05 2.2983e-06 8.2361e-04 5.7844e-04 0:00:23 109
42 5.5790e-02 6.0496e-05 1.4040e-04 3.9641e-05 2.0861e-06 7.7143e-04 5.3576e-04 0:00:23 108
43 5.1674e-02 5.5112e-05 1.2933e-04 3.6298e-05 1.9011e-06 7.2177e-04 4.9554e-04 0:00:23 107
44 4.7858e-02 5.0240e-05 1.1909e-04 3.3264e-05 1.7365e-06 6.7377e-04 4.5764e-04 0:00:23 106
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
45 4.4297e-02 4.5838e-05 1.0985e-04 3.0492e-05 1.5900e-06 6.2827e-04 4.2209e-04 0:00:22 105
46 4.0990e-02 4.1814e-05 1.0139e-04 2.7975e-05 1.4590e-06 5.8662e-04 3.8910e-04 0:00:22 104
47 3.8043e-02 3.8194e-05 9.3531e-05 2.5683e-05 1.3405e-06 5.4636e-04 3.5874e-04 0:00:22 103
48 3.5291e-02 3.4895e-05 8.6288e-05 2.3600e-05 1.2314e-06 5.0784e-04 3.3142e-04 0:00:22 102
49 3.2786e-02 3.1903e-05 7.9603e-05 2.1686e-05 1.1318e-06 4.7135e-04 3.0602e-04 0:00:22 101
50 3.0424e-02 2.9195e-05 7.3360e-05 1.9932e-05 1.0405e-06 4.3672e-04 2.8214e-04 0:00:21 100
51 2.8181e-02 2.6723e-05 6.7581e-05 1.8321e-05 9.5665e-07 4.0345e-04 2.5989e-04 0:00:21 99
52 2.5989e-02 2.4468e-05 6.2139e-05 1.6838e-05 8.7985e-07 3.7174e-04 2.3850e-04 0:00:21 98
53 2.4054e-02 2.2410e-05 5.7056e-05 1.5475e-05 8.0837e-07 3.4185e-04 2.1831e-04 0:00:21 97
54 2.2374e-02 2.0521e-05 5.2296e-05 1.4218e-05 7.4190e-07 3.1323e-04 1.9942e-04 0:00:21 96
55 2.0651e-02 1.8776e-05 4.7799e-05 1.3068e-05 6.8060e-07 2.8646e-04 1.8209e-04 0:00:20 95
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
56 1.9007e-02 1.7162e-05 4.3727e-05 1.2015e-05 6.2365e-07 2.6146e-04 1.6611e-04 0:00:20 94
57 1.7438e-02 1.5694e-05 4.0006e-05 1.1043e-05 5.7068e-07 2.3846e-04 1.5132e-04 0:00:20 93
58 1.5968e-02 1.4346e-05 3.6562e-05 1.0151e-05 5.2208e-07 2.1714e-04 1.3772e-04 0:00:20 92
59 1.4625e-02 1.3112e-05 3.3404e-05 9.3270e-06 4.7696e-07 1.9754e-04 1.2523e-04 0:00:20 91
60 1.3402e-02 1.1981e-05 3.0495e-05 8.5687e-06 4.3489e-07 1.8005e-04 1.1383e-04 0:00:20 90
61 1.2241e-02 1.0944e-05 2.7796e-05 7.8715e-06 3.9562e-07 1.6404e-04 1.0345e-04 0:00:19 89
62 1.1188e-02 9.9881e-06 2.5299e-05 7.2285e-06 3.5907e-07 1.4928e-04 9.3923e-05 0:00:22 88
63 1.0247e-02 9.1074e-06 2.3011e-05 6.6313e-06 3.2509e-07 1.3570e-04 8.5224e-05 0:00:21 87
64 9.3786e-03 8.3025e-06 2.0909e-05 6.0829e-06 2.9421e-07 1.2343e-04 7.7272e-05 0:00:20 86
65 8.5910e-03 7.5639e-06 1.8980e-05 5.5769e-06 2.6585e-07 1.1223e-04 7.0052e-05 0:00:20 85
66 7.8744e-03 6.8871e-06 1.7217e-05 5.1092e-06 2.3984e-07 1.0201e-04 6.3444e-05 0:00:19 84
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
67 7.2163e-03 6.2684e-06 1.5609e-05 4.6778e-06 2.1588e-07 9.2544e-05 5.7409e-05 0:00:19 83
68 6.6060e-03 5.7025e-06 1.4144e-05 4.2794e-06 1.9413e-07 8.3815e-05 5.1874e-05 0:00:18 82
69 6.0382e-03 5.1855e-06 1.2810e-05 3.9112e-06 1.7424e-07 7.5928e-05 4.6776e-05 0:00:18 81
70 5.5104e-03 4.7113e-06 1.1593e-05 3.5724e-06 1.5611e-07 6.8736e-05 4.2146e-05 0:00:18 80
71 5.0214e-03 4.2765e-06 1.0488e-05 3.2592e-06 1.3968e-07 6.2146e-05 3.7918e-05 0:00:17 79
72 4.5701e-03 3.8786e-06 9.4793e-06 2.9704e-06 1.2475e-07 5.6104e-05 3.4081e-05 0:00:17 78
73 4.1579e-03 3.5155e-06 8.5580e-06 2.7037e-06 1.1123e-07 5.0584e-05 3.0596e-05 0:00:17 77
74 3.7781e-03 3.1839e-06 7.7199e-06 2.4579e-06 9.8997e-08 4.5533e-05 2.7437e-05 0:00:16 76
75 3.4292e-03 2.8820e-06 6.9555e-06 2.2316e-06 8.7960e-08 4.0953e-05 2.4581e-05 0:00:16 75
76 3.1091e-03 2.6065e-06 6.2592e-06 2.0236e-06 7.8037e-08 3.6796e-05 2.1999e-05 0:00:16 74
77 2.8179e-03 2.3555e-06 5.6264e-06 1.8327e-06 6.9130e-08 3.3030e-05 1.9675e-05 0:00:16 73
iter continuity x-velocity y-velocity z-velocity energy k omega time/iter
78 2.5517e-03 2.1275e-06 5.0529e-06 1.6576e-06 6.1154e-08 2.9618e-05 1.7582e-05 0:00:15 72
79 2.3072e-03 1.9205e-06 4.5330e-06 1.4974e-06 5.4021e-08 2.6529e-05 1.5702e-05 0:00:15 71
80 2.0843e-03 1.7327e-06 4.0629e-06 1.3509e-06 4.7642e-08 2.3734e-05 1.4012e-05 0:00:15 70
81 1.8805e-03 1.5622e-06 3.6380e-06 1.2173e-06 4.1944e-08 2.1208e-05 1.2491e-05 0:00:15 69
82 1.6949e-03 1.4077e-06 3.2543e-06 1.0955e-06 3.6863e-08 1.8929e-05 1.1127e-05 0:00:15 68
83 1.5259e-03 1.2680e-06 2.9076e-06 9.8462e-07 3.2340e-08 1.6876e-05 9.9024e-06 0:00:14 67
84 1.3704e-03 1.1413e-06 2.5972e-06 8.8394e-07 2.8322e-08 1.5027e-05 8.8038e-06 0:00:14 66
85 1.2289e-03 1.0266e-06 2.3198e-06 7.9275e-07 2.4761e-08 1.3367e-05 7.8212e-06 0:00:14 65
86 1.1013e-03 9.2316e-07 2.0719e-06 7.1013e-07 2.1612e-08 1.1878e-05 6.9443e-06 0:00:14 64
87 9.8633e-04 8.2961e-07 1.8489e-06 6.3534e-07 1.8831e-08 1.0540e-05 6.1630e-06 0:00:14 63
! 87 solution is converged
False
Create velocity vectors#
Create and display velocity vectors on the symmetry-xyplane plane.
solver.results.graphics.vector["velocity_vector_symmetry"] = {}
solver.results.graphics.vector["velocity_vector_symmetry"].print_state()
solver.results.graphics.vector["velocity_vector_symmetry"].field = "temperature"
solver.results.graphics.vector["velocity_vector_symmetry"].surfaces_list = [
"symmetry-xyplane",
]
solver.results.graphics.vector["velocity_vector_symmetry"].scale.scale_f = 4
solver.results.graphics.vector["velocity_vector_symmetry"].style = "arrow"
Compute mass flow rate#
Compute the mass flow rate.
solver.solution.report_definitions.flux["mass_flow_rate"] = {}
solver.solution.report_definitions.flux["mass_flow_rate"].zone_names.get_attr(
"allowed-values"
)
solver.solution.report_definitions.flux["mass_flow_rate"].zone_names = [
"cold-inlet",
"hot-inlet",
"outlet",
]
solver.solution.report_definitions.flux["mass_flow_rate"].print_state()
solver.solution.report_definitions.compute(report_defs=["mass_flow_rate"])
Report Name Value Unit
------------------- ------------------- -----
{'mass_flow_rate': [-5.191642632018656e-06, 0]}
Close Fluent#
Close Fluent.
solver.exit()
Total running time of the script: ( 0 minutes 44.618 seconds)