Project 2: Heat Exchanger Design
Group Members:
Brian Schludecker
Phillip Palmer
Adam Spindler
Mike Hay
Joe McGuire
Presented 12/12/2006 to Dr. Toksoy and ME 414 Class, IUPUI
Project Summary
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•
•
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•
Design and optimization of heat exchanger
Specifications & objectives
Methods
Results
Conclusions
Heat Exchanger Specifications
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•
•
•
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Heat exchanger length must not exceed 7 m
Shell diameter must not exceed 2 m
Shell mass flow rate: 120,000 kg/hr
Water in shell must cool from 40 C to 25 C
Water in tube enters at 20 C
Ignore fouling
Objectives
• Maximize Q
• Minimize Weight (cost)
• Minimize heat exchanger pressure drop
Design Strategy
• Configure MATLAB files to analyze the
heat exchanger
• Modify input factors until heat transfer ratio
is close to 1
• Run DOE in MATLAB and Minitab to
calculate optimal values for system
Design Factors
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•
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Tube outer diameter
Shell inner diameter
Tube length
Number of tube passes
Material
Pitch
Number of Baffles
Baffle Spacing
Design Factors for DOE
•
•
•
•
•
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Tube outer diameter
Shell inner diameter
Tube length
Number of tube passes
Material
Pitch
Number of Baffles
Baffle Spacing
Design Decisions
• Pitch = 1.25 * Tube outer diameter
• 0 baffles
Interaction & Main Effects Plots
(to find Critical Factors)
Interaction Plot (data means) for dp shell
Interaction Plot (data means) for dp tube
0.3874
0.4382
2
5
1
2
3
0.3874
21
1600000
800000
tube_od
0
1600000
800000
shell_id
0
1600000
800000
tube_len
0
1600000
800000
tube_pass
tube_od
0.00635
0.01270
shell_id
0.3874
0.4382
tube_len
2
5
tube_pass
1
2
0.4382
2
5
1
2
3
21
3000
2000
tube_od
1000
3000
2000
shell_id
1000
3000
2000
tube_len
1000
3000
2000
tube_pass
1000
0
tub_mat
tub_mat
tube_od
0.00635
0.01270
shell_id
0.3874
0.4382
tube_len
2
5
tube_pass
1
2
Interaction & Main Effects Plots
(to find Critical Factors)
Interaction Plot (data means) for weight
0.3874
0.4382
2
5
1
2
3
Interaction Plot (data means) for q
21
0.3874
1800
1200
tube_od
tube_od
0.00635
0.01270
0.4382
2
5
1
2
3
21
4500000
3000000
tube_od
1500000
600
1800
1200
shell_id
shell_id
0.3874
0.4382
4500000
3000000
shell_id
1500000
600
1800
1200
tube_len
tube_len
2
5
4500000
3000000
tube_len
1500000
600
1800
1200
tube_pass
tube_pass
1
2
4500000
3000000
tube_pass
1500000
600
tub_mat
tube_od
0.00635
0.01270
tub_mat
shell_id
0.3874
0.4382
tube_len
2
5
tube_pass
1
2
Mean Effects Plots
Main Effects Plot (data means) for dp tube
tube_od
shell_id
Main Effects Plot (data means) for dp shell
tube_len
tube_od
800000
shell_id
tube_len
2500
600000
2000
200000
0
0.00635
0.01270
tube_pass
0.3874
0.4382
2
5
tub_mat
800000
Mean of dp shell
Mean of dp tube
400000
1500
1000
0.00635
0.01270
0.3874
tube_pass
0.4382
2
5
tub_mat
2500
600000
2000
400000
1500
200000
0
1000
1
2
3
21
1
2
Main Effects Plot (data means) for weight
shell_id
tube_od
1500
3000000
1250
2500000
1000
2000000
750
1500000
500
0.00635
0.01270
0.3874
tube_pass
0.4382
tub_mat
1500
2
21
Main Effects Plot (data means) for q
tube_len
5
Mean of q
Mean of weight
tube_od
3
shell_id
tube_len
1000000
0.00635
0.01270
tube_pass
0.3874
0.4382
tub_mat
3000000
1250
2500000
1000
2000000
750
1500000
500
1000000
1
2
3
21
1
2
3
21
2
5
Pareto Charts
Pareto Chart of the Effects
Pareto Chart of the Effects
(response is dp tube, Alpha = .10, only 30 largest effects shown)
(response is dp shell, Alpha = .10, only 30 largest effects shown)
0
F actor
A
B
C
D
E
N ame
tube_od
shell_id
tube_len
tube_pass
tub_mat
Term
Term
0
A
D
AD
C
AC
CD
ACD
B
AB
BD
ABD
BC
ABC
BCD
A BCD
ADE
ACE
AE
A CDE
DE
A BCE
ABCDE
CE
BDE
BCDE
CDE
BCE
BE
A BDE
ABE
0
A
B
AB
D
AD
BD
ABD
ADE
AE
A CDE
BCD
ACD
ACE
CDE
A BCE
A BCD
CD
ABE
BE
BC
C
E
BDE
BCE
BCDE
ABC
AC
CE
ABCDE
DE
0
100000 200000 300000 400000 500000 600000 700000 800000
Effect
Lenth's PSE = 1.345648E-10
800
1000
Effect
1200
1400
F actor
A
B
C
D
E
N ame
tube_od
shell_id
tube_len
tube_pass
tub_mat
1600
Pareto Chart of the Effects
8
F actor
A
B
C
D
E
N ame
tube_od
shell_id
tube_len
tube_pass
tub_mat
Term
Term
600
N ame
tube_od
shell_id
tube_len
tube_pass
tub_mat
(response is weight, Alpha = .10, only 30 largest effects shown)
138331
A
C
D
AC
E
AD
CD
AE
CE
ACD
DE
B
ACE
ADE
AB
CDE
BC
BD
A CDE
ABC
ABD
BCD
A BCD
BDE
BE
A BDE
BCDE
BCE
ABCDE
ABE
Lenth's PSE = 76571.9
400
Lenth's PSE = 1.179762E-13
Pareto Chart of the Effects
(response is q, Alpha = .10, only 30 largest effects shown)
0
200
F actor
A
B
C
D
E
500000
1000000
Effect
1500000
2000000
C
E
A
CE
B
AE
AC
BC
BE
A CE
BCE
AB
A BE
D
A BC
DE
ABCE
CD
AD
C DE
A DE
BD
A CD
BDE
AC DE
BCD
BC DE
A BD
ABDE
ABCD
0
200
400
600
Effect
Lenth's PSE = 4.38469
800
1000
Design Decisions
• Critical factors: Length, Shell ID, Tube OD
• Material: Aluminum (cost, weight)
• 1 pass
Optimized Results
Using guesses (from Matlab):
Optimal
Hi
D
Cur
0.62872 Lo
tube_od
0.0159
[0.0138]
0.0064
shell_id
0.4890
[0.4890]
0.3874
tube_len
5.0
[3.1253]
2.0
New
Hi
D
Cur
0.67904 Lo
weight
Minimum
y = 713.3242
d = 0.69525
weight
Targ: 1100.0
y = 1076.0802
d = 0.94020
dp shell
Minimum
y = 828.8276
d = 0.67117
dp shell
Minimum
y = 416.0955
d = 0.41952
+/- 20% 
dp tube
Minimum
y = 3862.8936
d = 0.68952
dp tube
Minimum
y = 1357.6620
d = 0.88078
q
Maximum
y = 1.971E+06
d = 0.48564
q
Targ: 2000000.0
y = 1.806E+06
d = 0.61200
tube_od
0.0166
[0.0148]
0.0110
shell_id
0.5868
[0.5861]
0.3912
tube_len
3.750
[3.3682]
2.50
Optimized results are not standard
Size ID and OD, choose close sizes:
Optimized Specifications
• Tube OD = 0.0127 mm
• Shell ID = 0.5906 m
• Length = 3.3682 m
Final Results
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Q maximized
dP in shell minimized
dP in tube minimized
Weight minimized
2.099E6 W
463 Pa
1500 Pa
1108 kg
Conclusions
• Minitab optimized values for ID and OD are
not standard tube/shell sizes, need to adjust
Minitab results
• Objectives achieved
• Further analysis possible for multiple
passes/baffles
• Questions?