SIMULATION REPORT FOR CASE
2_storeys_room
Summary
No comments were added.
INDEX
• Summary
• INDEX
• 1. Identification
• 2. Case Description
• 3. Computational Model
◦ 3.1. Simulation Times
◦ 3.2. Mesh Description
◦ 3.3. Execution Method
◾ 3.3.1. Subdomains
◦ 3.4. Solver and Turbulence Model
◦ 3.5. Fluid Properties
◦ 3.6. Boundary Conditions
• 4. Results
◦ 4.1. Efficiency Measurements
◦ 4.2. Graphs
◦ 4.3. Field Values
• 5. Conclusions
• Appendix A
◦ I. Mesh Quality Diagnosis
◦ II. Graphs
1. Identification
User ID: cdiaz
Project name: 2_storeys_room
Model name: 2_storeys_room
Machine ID: LAPTOP-M41RGKQO
Date of last simulation: 2020-02-21 23:10:42
Report #: 1
Back to Index
2. Case Description
Name: 2_storeys_room
Creation date: 2020-02-21 22:58:09
Last edited: 2020-02-21 23:10:45
Back to Index
3. Computational Model
3.1. Simulation Times
Current simulation final time: 2020-02-21 23:10:42
Total simulation duration: 00:04:39
Back to Index
3.2. Mesh Description
Mesh refinement
Global mesh resolution level: coarse
Base mesh resolution: 0.5 m
Mesh stats
points 81972
faces 205740
internal faces 180138
cells 61967
faces per cell 6.2271532
boundary patches 26
point zones 0
face zones 0
cell zones 0
Overall number of cells of each type
hexahedra 57788
prisms 0
wedges 0
pyramids 0
tet wedges 0
tetrahedra 0
polyhedra 4179
Breakdown of polyhedra by number of faces:
faces number of cells
4 1
5 4
6 108
9 3486
12 532
15 48
Cell volume
Minimum cell volume = 4.806E-04 m³
Mean cell volume = 4.663E-03 m³
Mode cell volume = 1.922E-03 m³
Maximum cell volume = 1.602E-02 m³
Cell resolution (aprox.)
Minimum cell resolution = 7.833E-02 m
Mean cell resolution = 1.671E-01 m
Mode cell resolution = 1.243E-01 m
Maximum cell resolution = 2.521E-01 m
Back to Index
3.3. Execution Method
The solver is running in parallel.
Decomposition method: scotch
Version of MPI: MS-MPI 2008R2
Number of partitions = 6
Back to Index
3.3.1. Subdomains
Processor 0
• Number of cells = 10329
• Number of faces shared with processor 2 = 512
• Number of processor patches = 1
• Number of processor faces = 512
• Number of boundary faces = 5078
Processor 1
• Number of cells = 10327
• Number of faces shared with processor 2 = 560
• Number of processor patches = 1
• Number of processor faces = 560
• Number of boundary faces = 4242
Processor 2
• Number of cells = 10338
• Number of faces shared with processor 0 = 512
• Number of faces shared with processor 1 = 560
• Number of faces shared with processor 3 = 175
• Number of processor patches = 3
• Number of processor faces = 1247
• Number of boundary faces = 3991
Processor 3
• Number of cells = 10246
• Number of faces shared with processor 2 = 175
• Number of faces shared with processor 4 = 241
• Number of faces shared with processor 5 = 294
• Number of processor patches = 3
• Number of processor faces = 710
• Number of boundary faces = 4333
Processor 4
• Number of cells = 10409
• Number of faces shared with processor 3 = 241
• Number of faces shared with processor 5 = 673
• Number of processor patches = 2
• Number of processor faces = 914
• Number of boundary faces = 4052
Processor 5
• Number of cells = 10318
• Number of faces shared with processor 3 = 294
• Number of faces shared with processor 4 = 673
• Number of processor patches = 2
• Number of processor faces = 967
• Number of boundary faces = 3906
Back to Index
3.4. Solver and Turbulence Model
Solver: bCsimple - for incompressible, turbulent, steady-state flow
Turbulence model: SST k-omega
Back to Index
3.5. Fluid Properties
Fluid properties setting time: 2020-02-21 23:03:33
International standard atmosphere fluid properties:
Altitude: 0 m
Temperature offset: 0 K
Pressure: 1.013E+05 Pa
Temperature: 288.1 K
Specific heat capacity: 1004 J/kg.K
Thermal conductivity: 0.02441 W/m.K
Density: 1.225 kg/m³
Dynamic viscosity: 1.79118e-05 Pa-s
Molecular diffusivity: 2.88E-05 m²/s
Turbulent Schmidt number: 0.7
Gravity: (0, 0, -9.81) m/s²
Tracers:
Custom_Gas1:
Molecular diffusivity: 2.88e-05 m2/s
Turbulent Schmidt number: 0.9
Back to Index
3.6. Boundary Conditions
Boundary conditions setting time: 2020-02-21 23:04:52
Ground_Floor:
Walls:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Ground_Floor_Entrance:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Ground_Floor_Window_01:
Status: Natural Circulation
Fluid pressure: 0.000e+00 Pa
Fluid total pressure: 1.013e+05 Pa
Fluid turbulence intensity: 5.000e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_02:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Ground_Floor_Window_03:
Status: Natural Circulation
Fluid pressure: 0.000e+00 Pa
Fluid total pressure: 1.013e+05 Pa
Fluid turbulence intensity: 5.000e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_04:
Status: Natural Circulation
Fluid pressure: 0.000e+00 Pa
Fluid total pressure: 1.013e+05 Pa
Fluid turbulence intensity: 5.000e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_05:
Status: Natural Circulation
Fluid pressure: 0.000e+00 Pa
Fluid total pressure: 1.013e+05 Pa
Fluid turbulence intensity: 5.000e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_06:
Status: Normal Insufflation
Fluid velocity: 1.000e+00 m/s
Fluid direction: (-1.000e+00 0.000e+00 0.000e+00) m
Velocity profile: threshold
Fluid turbulence intensity: 3.958e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_07:
Status: Swirl Insufflation
Fluid velocity: 1.000e+00 m/s
Revolutions per minute: 0.000e+00
Velocity profile: threshold
Fluid turbulence intensity: 3.958e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_08:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Ground_Floor_Window_09:
Status: Natural Circulation
Fluid pressure: 0.000e+00 Pa
Fluid total pressure: 1.013e+05 Pa
Fluid turbulence intensity: 5.000e-02
Tracers concentration:
Custom_Gas1: 0
Ground_Floor_Window_10:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Ground Floor <-> First Floor:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor:
Walls:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_01:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_02:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_03:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_04:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_05:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_06:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_07:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_08:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_09:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_10:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_11:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
First_Floor_Window_12:
Status: Closed
Tracers flux:
Custom_Gas1: 0.000e+00 kg/(m2s)
Back to Index
4. Results
This section encompasses:
1. Efficiency measures, which categorize the air quality of the selected spaces;
2. Charts and images of the mesh, evolution of the simulation, and results;
3. Field values at probe locations.
Terminology for this simulation:
• Breathing zone = region within an occupied space between planes 0.075 and 1.8 m above the floor and
more than 0.6 m from the walls or fixed air-conditioning equipment, or the whole domain if the
computational domain returns an empty breathing zone, given the previous criteria.
• Comfort zone = isosurface with velocity magnitude equal to 0.2 m/s.
• Discomfort zone = isosurface with velocity magnitude equal to 0.3 m/s.
Back to Index
4.1. Efficiency Measurements
Air parameters
Total inlet ventilation (Qin) = 2.4 m³/s
Total outlet ventilation (Qout) = 2.4 m³/s
Mean age of air (Ageavg) = 1374 s
Standard deviation of age of air = 1409 s
Mean velocity of air (Uavg) = 0.1756 m/s
Standard deviation of velocity of air = 0.2447 m/s
Air changes per hour (ACH) = 29.9 AC/h
Air change effectiveness (ACE) = 8.764
Air parameters expressions:
Ageavg = spatial average of the age of all air particles in the breathing zone.
Uavg = spatial average of the velocity magnitude of all air particles in the breathing zone.
ACH = 3600 × Qin / V
ACE = V /(Qin × Ageavg)
V = volume of the space.
Back to Index
4.2. Graphs
The graphs displayed in this section represent different aspects of the generated mesh, the evolution of the
quality indicators and the automatic results:
1. Distribution of the volume of the cells;
2. Mesh section cut (X);
3. Mesh section cut (Y);
4. Mesh section cut (Z);
5. Mesh overview;
6. Quality plot;
7. Maximum age of air in the breathing zone (s);
8. Maximum air velocity in the breathing zone (m/s);
9. Velocity (m/s) at ankle level (0.1 m);
10. Velocity (m/s) at head level for seated occupants (1.1 m);
11. Velocity (m/s) at head level for standing occupants (1.7 m);
12. Age of air (s) at head level for seated occupants (1.1 m);
13. Age of air (s) at head level for standing occupants (1.7 m);
14. Comfort zone (U=0.2 m/s);
15. Discomfort zone (U=0.3 m/s);
16. Both comfort and discomfort zones (U=0.2 m/s in green and U=0.3 m/s in red).
Figure 1: Distribution of the volume of the cells.
Figure 2: Mesh section cut (X).
Figure 3: Mesh section cut (Y).
Figure 4.1: Mesh section cut (Z) of level 0.
Figure 4.2: Mesh section cut (Z) of level 1.
Figure 5: Mesh overview.
Figure 6: Quality plot.
Figure 7: Maximum age of air in the breathing zone (s).
Figure 8: Maximum air velocity in the breathing zone (m/s).
Figure 9: Velocity (m/s) at ankle level (0.1 m).
Figure 10: Velocity (m/s) at head level for seated occupants (1.1 m).
Figure 11: Velocity (m/s) at head level for standing occupants (1.7 m).
Figure 12: Age of air (s) at head level for seated occupants (1.1 m).
Figure 13: Age of air (s) at head level for standing occupants (1.7 m).
Figure 14: Comfort zone (U=0.2 m/s).
Figure 15: Discomfort zone (U=0.3 m/s).
Figure 16: Both comfort and discomfort zones (U=0.2 m/s in green and U=0.3 m/s in red).
Back to Index
4.3. Field Values
The values and positions of the maximum air velocity magnitude and age of air in the breathing zone are
displayed in Table 1.
Table 1: Maximum velocity magnitude and age of air.
Value Position (x,y,z)
Velocity Magnitude (m/s) 2.045 (9.375, 3.125, 1.691)
Age of Air (s) 4668 (0.625, 0.625, 4.253)
Back to Index
5. Conclusions
The tabulated values of the minimum people outdoor air rate, area outdoor air rate and default occupant
density for several occupancy categories are displayed in Table 2.
The minimum breathing zone outdoor airflow, also displayed in Table 2, is calculated from these values and
from the floor area of the selected space.
The outdoor air intake flow and air changes per hour are displayed in Table 3.
Note that the minimum ventilation air required is about 1.3 ACH for a space with a 2.75 m ceiling.
Table 2: Minimum ventilation rates in breathing zone.
People Outdoor Area Outdoor Default Occupant Breathing zone
Occupancy Category Air Rate Air Rate Density outdoor airflow
(L/s.person) (L/s.m²) (#/100m²) (L/s)
Lecture classroom 3.8 0.3 65 260.048
Restaurant dining
3.8 0.9 70 334.213
rooms
Bedroom/living room 2.5 0.3 10 51.634
Office space 2.5 0.3 5 39.899
Museum/gallery 3.8 0.3 40 170.862
Health club/aerobics
10 0.3 40 403.684
room
Legend:
People Outdoor Air Rate (Rp): outdoor airflow rate per person to be provided in the breathing zone to dilute
contaminants that are emitted at a rate that is related more to population than to floor area.
Area Outdoor Air Rate (Ra): outdoor airflow rate per unit area to be provided in the breathing zone to dilute
contaminants that are emitted at a rate that is related more to floor area than to population.
Space population (Pbz): largest number of people expected to occupy the space during typical usage. If not
known, it is determined from the default occupant density.
Breathing zone floor area (Abz): net occupiable floor area of the space.
Breathing zone outdoor airflow (Vbz): outdoor airflow required in the breathing zone of an occupiable space,
Vbz = RpPbz + RaAbz.
Table 3: Outdoor air intake flow and air changes per hour.
Outdoor Air Intake Flow Air Changes Per Hour
(L/s) (AC/h)
2400 29.9
Back to Index
Appendix A
I. Mesh Quality Diagnosis
Checking topology...
Checking patch topology for multiply connected surfaces ...
Checking geometry...
Overall domain bounding box (0 0 9.5367432e-008) (10 5 6.1999999)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (-5.9867296e-017 2.1470354e-017 -2.8128881e-017) OK.
Max cell openness = 2.7189243e-016 OK.
Max aspect ratio = 4.2664967 OK.
Minimum face area = 0.0016067036. Maximum face area = 0.0640625. Face area
magnitudes OK.
Min volume = 0.00048064561. Max volume = 0.016015625. Total volume =
288.95385. Cell volumes OK.
Mesh non-orthogonality Max: 51.327592 average: 8.3771829
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.4353613 OK.
Coupled point location match (average 0) OK.
Mesh OK.
Back to Index
II. Graphs
Figure 15: Residuals plot.
Back to Index
Document generated by blueCFD-AIR on 2020-02-21 23:12:46
