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TABLE OF CONTENT
1.0 INTRODUCTION TO THE PROBLEM 2
2.0 PICTURE OF THE ROOM 2
3.0 DESCRIPTION AND ASSUMPTIONS 3
4.0 DESCRIPTION ON THE BOUNDARY CONDITIONS 3
5.0 RESULTS, ANALYSIS AND DISCUSSIONS 4
5.1 First Conditions 4
5.2 Second Conditions 8
5.3 Third Conditions 11
6.0 CONCLUSION 14
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1.0 INTRODUCTION TO THE PROBLEM
As a group of consultant, we were required to make analysis in Dr. Norshah room by using
our CFD expertise to simulate the air velocity and temperature distribution in his room. Dr
Norshah is saying that the air in his room feels stagnant and quiet hot. The dimension of his
room is 3.5 x 4.5 m. The height of the ceiling is 2.5m. There were couples of furniture such
desk, chair and cupboards. There are three big cupboards lay in front of the wall and one
small cabinet and desk. There is one source of air inflow to the room on the ceiling with 0.5 x
0.5 m of dimension and one for outflow. It can be assume that no air leak through the window
and door.
2.0 THE REAL PICTURE OF THE ROOM
2
CUPBOARD
CUPBOARD
DESK
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3.0 DESCRIPTION ON THE CFD MODEL AND ASSUMPTIONS MADE
1. Model 3D design of Dr. Norshah Room using Gambit with unstructured mesh and size
function below 100,000.
2. Make an analysis using Fluent by taking assumption of three differents air temperature and
velocity from one inlet and one outlet at his room:
i. 1 m/s and 14oC
ii. 2 m/s and 15oC
iii. 3 m/s and 16oC
3. Assumption for initial room temperature = 27oC (300K)
4. Adiabatic walls, windows and doors. (no heat transfer)
5. Neglect the heat from any souce including sun radiations, computer and printer.
4.0 DESCRIPTION ON THE BOUNDARY CONDITIONS
Figure 1: Description of the boundary condition
3
Velocity
Lecturer
PressureCabine
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5.0 RESULT, ANALYSIS AND DISCUSSION
Model the room with the cabinet, inlet and outlet section using Gambit. Mesh using
unstuctured mesh and size function and achieve the total mesh below 100,000. The result
shown in a Figure 2 with total mesh achieved is 81,490.
Figure 2: Result of Unstructured Mesh using Gambit
5.1 First Condition
- Inlet Velocities = 1m/s
- Inlet Temperature = 14oC
Figure 3: Residual Plot with Velocity and Energy Iterations
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Figure 4: Velocity Vector Plot
From the Figure 4, notice that cooled air entering the room is from the inlet with the velocity
of 1m/s (yellow colour indicator). In a moment of circulation process inside the room, the
velocities become around 0.15-0.20 m/s through the whole area inside the room (blue colour
indicator). From the analysis gathered, compute the flux report of Mass Flow Rate in the inlet
and outlet session.
Mass Flow Rate (kg/s)
-------------------------------- ------------------
inlet 0.44100001
outlet -0.44161516
---------------- --------------------Net -0.00061515202
Next, turn on the energy equation to add the temperature equation. Set the air inlet
temperature as 14oC.
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Figure 5: Velocity Vector Plot with Temperature
From the Figure 5, notice that the inlet temperature is 287K (14 oC) from the dark blue colour
indicator. Since the process of circulation in the room, the temperature becomes around 292
K (19oC) major distributions inside the room (light blue colour indicator).
Below are the result gained for Total Heat Transfer Rate inside the room.
Total Heat Transfer Rate (w)
-------------------------------- --------------------
inlet -4948.7677
outlet 3474.8674
---------------- --------------------
Net -1473.9003
In order to monitor the temperature and velocity at the visitor sitter and lecturer sitter, create
two points in the Fluent and run the analysis to get the result. Figure 6 below show the two
points created which is the place need to run the analysis.
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Figure 6: Two Points Created
Below are the result obtained:
Average of Surface Vertex Values
Static Temperature (k)
-------------------------------- --------------------
point-lecturer 290.19949
point-visitor 290.10187
---------------- --------------------
Net 290.1507
Average of Surface Vertex Values
Velocity Magnitude (m/s)
-------------------------------- --------------------
point-lecturer 0.071613178
point-visitor 0.11196788
---------------- --------------------
Net 0.091790527
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Visitor
Lecturer
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5.2 Second Condition
- Inlet Velocities = 2m/s
- Inlet Temperature = 15oC
Figure 7: Residual Plot with Velocity and Energy Iterations
Figure 8: Velocity Vector Plot
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From the Figure 8, notice that cooled air entering the room is from the inlet with the velocity
of 2m/s (yellow colour indicator). In a moment of circulation process inside the room, the
velocities become around 0.30-0.45 m/s through the whole area inside the room (blue colour
indicator). From the analysis gathered, compute the flux report of Mass Flow Rate in the inlet
and outlet session.
Mass Flow Rate (kg/s)
-------------------------------- --------------------
inlet 0.88200002
outlet -0.88299642
---------------- --------------------
Net -0.00099640621
Next, turn on the energy equation to add the temperature equation. Set the air inlet
temperature as 15oC.
Figure 9: Velocity Vector Plot with Temperature
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From the Figure 9, notice that the inlet temperature is 288K (15 oC) from the dark blue colour
indicator. Since the process of circulation in the room, the temperature becomes around 293
K (20oC) major distributions inside the room (light blue colour indicator).
Below are the result gained for Total Heat Transfer Rate inside the room.
Total Heat Transfer Rate (w)
-------------------------------- --------------------
inlet -9009.8635
outlet 7505.4174
---------------- --------------------
Net -1504.4461
In order to monitor the temperature and velocity at the visitor sitter and lecturer sitter, two
points has been created before. Figure 6 above show the two points created which is the place
need to run the analysis. Below are the results obtained.
Average of Surface Vertex Values
Static Temperature (k)
-------------------------------- --------------------
point-lecturer 289.82498
point-visitor 289.59229
---------------- --------------------
Net 289.70862
Average of Surface Vertex Values
Velocity Magnitude (m/s)-------------------------------- --------------------
point-lecturer 0.092320308
point-visitor 0.23817956
---------------- --------------------
Net 0.16524994
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5.3 Third Condition
- Inlet Velocities = 3m/s
- Inlet Temperature = 16oC
Figure 10: Residual Plot with Velocity and Energy Iterations
Figure 11: Velocity Vector Plot
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From the Figure 11, notice that cooled air entering the room is from the inlet with the velocity
of 3m/s (yellow colour indicator). In a moment of circulation process inside the room, the
velocities become around 0.40-0.60 m/s through the whole area inside the room (blue colour
indicator). From the analysis gathered, compute the flux report of Mass Flow Rate in the inlet
and outlet session.
Mass Flow Rate (kg/s)
-------------------------------- --------------------
inlet 1.323
outlet -1.3243461
---------------- --------------------
Net -0.0013460967
Next, turn on the energy equation to add the temperature equation. Set the air inlet
temperature as 16oC.
Figure 12: Velocity Vector Plot with Temperature
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From the Figure 12, notice that the inlet temperature is 289K (16oC) from the dark blue
colour indicator. Since the process of circulation in the room, the temperature becomes
around 294 K (21oC) major distributions inside the room (light blue colour indicator).
Below are the result gained for Total Heat Transfer Rate inside the room.
Total Heat Transfer Rate (w)
-------------------------------- --------------------
inlet -12183.288
outlet 10707.086
---------------- --------------------
Net -1476.2026
In order to monitor the temperature and velocity at the visitor sitter and lecturer sitter, two
points has been created before. Figure 6 above show the two points created which is the place
need to run the analysis. Below are the results obtained.
Average of Surface Vertex Values
Static Temperature (k)
-------------------------------- --------------------
point-lecturer 290.18076
point-visitor 290.04541
---------------- --------------------
Net 290.1131
Average of Surface Vertex Values
Velocity Magnitude (m/s)-------------------------------- --------------------
point-lecturer 0.15542695
point-visitor 0.35418814
---------------- --------------------
Net 0.25480753
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6.0 CONCLUSION
Where:i. 1 m/s and 14oC
ii. 2 m/s and 15oC
iii. 3 m/s and 16oC
Name of Group Members Mark Weightage SignatureMOHD HAFIZ BIN MUHAIYADIN ( ME 079689 ) 1
MOHD AZIZUL BIN ABD AZIZ ( ME 080181 ) 1MUHAMAD WAQAR HAMMAN B ALIAS ( ME 080092 ) 1
MOHAMAD HIDAYAT BIN ZAINUL MASRI (ME 080124) 1
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Mass Flow Rate
(kg/s)
Total Heat Transfer
(kW)
Static Temperature
(oC)
Velocity Magnitude
(m/s)
i ii iii i ii iii i ii iii i ii iii
Inlet 0.441 0.882 1.323 4.95 9.01 12.18 - - - - - -
Outlet 0.442 0.883 1.324 3.47 7.51 10.71 - - - - - -
Lecturer-Pt - - - - - - 17.20 16.82 17.18 0.072 0.092 0.155
Visitor-Pt - - - - - - 17.10 16.59 17.05 0.111 0.238 0.354