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transcript
ME 414 Project 2Heat Exchanger Design
Date: - May 6, 2009Instructor: - John Toksoy
Member: - Rahul Patel Hesam Nouri Atoosa Solhkonan Juan Tapia
Appendix
• Problem Defined• Objective and Specification• Design Heat Exchanger• Results Summary• Conclusion
Problem Defined• Chemical temperature must be cooled by at
least 20 degrees Celsius• Mass flow rate is 220,000 kg/hr.• Material properties must be defined as water.• City Water Temperature must be 20 C.• Length of the heat exchanger can not exceed 7
meters.• Minimize pressure drop, shell and tube weight.• Shell Diameter should not exceed 2 meters.
Objective
• Calculate the heat transfer ratio between 0.95 and 1.
• Minimize the weight of the Heat Exchanger.• Minimize the pressure drop for the shell and
tube side.
Design Heat Exchanger
• First use notes and your experience to eliminate the variables.
• Use matlab and Minitab to run the DOE on the variable to see their effect.
• Find the final 4 or 5 variables that effect the heat exchanger design.
Variables• Shell and Tube Fluid• Mdot Shell and Tube• Temperature of Shell in and Out• Temperature of Tube in and Out• Rf of Tube in• Rf of Tube Shell side• Shell tube side fluid reversed• Type of Flow• Number of shell and tube pass• Type of baffle• Baffle space and cut• Shell ID and thickness• Nusselt Shell and Tube• Pressure shell and Tube• Tube OD and thickness• Tube length and number of tubes• Tube Pithch and layout angle
Input Variables
• Shell and Tube Fluid: Water• Temperature of Shell in: 20 C• Temperature of Tube in: 45 C• Temperature of Tube Out: 25 C• Type of flow: Counter flow• Number of tube pass: 1• Number of Shell pass: 1
Design of Experiment (DOE)
• Total variables: 32• Eliminated 22 variables including the inputs
using notes and experiences.• 10 Variables so 2 DOE for 5 variables in each• Reduced 6 variables using DOE• Final Variables: Mdot shell, Shell ID, Tube OD
and length,
First DOE: Main Effect Plots
1.250.75
1000000
0
-1000000
500300 8.1254.875
0.6508750.390525
1000000
0
-1000000
0.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for q (des - calc)Data Means
1.250.75
5500000
5250000
5000000
4750000
4500000500300 8.1254.875
0.6508750.390525
5500000
5250000
5000000
4750000
45000000.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for q DesiredData Means
1.250.75
6000000
5000000
4000000
500300 8.1254.875
0.6508750.390525
6000000
5000000
4000000
0.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for q CalcData Means
1.250.75
320
280
240
200500300 8.1254.875
0.6508750.390525
320
280
240
2000.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for DP TubeData Means
1.250.75
12000000
10000000
8000000
6000000
4000000
500300 8.1254.875
0.6508750.390525
12000000
10000000
8000000
6000000
4000000
0.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for DP shellData Means
1.250.75
16000
14000
12000
10000
500300 8.1254.875
0.6508750.390525
16000
14000
12000
10000
0.00111130.0006668
I_counter_flow
Mean
mdot_shell Tube_Len
Baffle_Space Tube_th
Main Effects Plot for Weight_HEData Means
First DOE: Pareto Charts
BC
CD
C
BD
B
D
50403020100
Term
Standardized Effect
2.06
B mdot_shellC Tube_LenD Baffle_Space
Factor Name
Pareto Chart of the Standardized Effects(response is DP shell, Alpha = 0.05)
mdot_shell
Baffle_Space
Tube_th
Tube_Len
160140120100806040200
Term
Standardized Effect
2.1
Pareto Chart of the Standardized Effects(response is q Calc, Alpha = 0.05)
BC
D
B
E
C
200150100500
Term
Standardized Effect
2.1
B mdot_shellC Tube_LenD Baffle_SpaceE Tube_th
Factor Name
Pareto Chart of the Standardized Effects(response is q (des - calc), Alpha = 0.05)
Tube_th
Tube_Len
80706050403020100
Term
Standardized Effect
2.05
Pareto Chart of the Standardized Effects(response is Weight_HE, Alpha = 0.05)
Tube_th
Tube_Len
50403020100
Term
Standardized Effect
2.05
Pareto Chart of the Standardized Effects(response is DP Tube, Alpha = 0.05)
First DOE: Optimization
CurHigh
Low0.93553D
Optimal
d = 0.96800
Targ: 8400.0Weight_H
y = 8451.2000
d = 0.97762
Targ: 5150000.0DP shell
y = 5.236E+06
d = 0.78200
Targ: 185.0DP Tube
y = 188.270
d = 0.98511
Targ: 3800000.0q Calc
y = 3.781E+06
d = 0.98300
Targ: 1300000.0q (des -
y = 1.303E+06
0.93553DesirabilityComposite
0.0007
0.0011
0.3905
0.6509
4.8750
8.1250
300.0
500.0Tube_LenBaffle_S Tube_thmdot_she
[302.0202][4.8750] [0.3905] [0.0007]
Second DOE: Main Effect Plots
0.4953000.371475
1000000
0
-1000000
1.238250.74295 2.51.5
0.02381250.0142875
1000000
0
-1000000
0.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for q (Des - calc)Data Means
0.4953000.371475
5500000
5250000
5000000
4750000
45000001.238250.74295 2.51.5
0.02381250.0142875
5500000
5250000
5000000
4750000
45000000.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for q DesiredData Means
0.4953000.371475
6500000
6000000
5500000
5000000
4500000
1.238250.74295 2.51.5
0.02381250.0142875
6500000
6000000
5500000
5000000
4500000
0.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for q CalcData Means
0.4953000.371475
1000
750
500
250
01.238250.74295 2.51.5
0.02381250.0142875
1000
750
500
250
00.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for DP TubeData Means
0.4953000.371475
8000000
7000000
6000000
5000000
40000001.238250.74295 2.51.5
0.02381250.0142875
8000000
7000000
6000000
5000000
40000000.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for DP ShellData Means
0.4953000.371475
14000
12000
10000
80001.238250.74295 2.51.5
0.02381250.0142875
14000
12000
10000
8000
0.02750.0165
Baffle_Cut
Mean
Shell_ID I_Shell_mat
Tube_OD Shell_th
Main Effects Plot for Weight_HEData Means
Second DOE: Pareto Charts
BE
BC
CE
E
D
C
B
200150100500
Term
Standardized Effect
2.1
B Shell_IDC I _Shell_matD Tube_ODE Shell_th
Factor Name
Pareto Chart of the Standardized Effects(response is Weight_HE, Alpha = 0.05)
Shell_ID
Tube_OD
302520151050Te
rmStandardized Effect
2.05
Pareto Chart of the Standardized Effects(response is DP Shell, Alpha = 0.05)
Tube_OD
120010008006004002000
Term
Effect
Pareto Chart of the Effects(response is DP Tube, Alpha = 0.05)
Shell_ID
Tube_OD
100806040200
Term
Standardized Effect
2.0
Pareto Chart of the Standardized Effects(response is q Calc, Alpha = 0.05)
Shell_ID
Tube_OD
100806040200
Term
Standardized Effect
2.0
Pareto Chart of the Standardized Effects(response is q (Des - calc), Alpha = 0.05)
Second DOE: Optimization
CurHigh
Low0.84011D
Optimal
d = 0.99949
Targ: 11500.0Weight_H
y = 1.150E+04
d = 0.99223
Targ: 6500000.0DP Shell
y = 6.496E+06
d = 0.63891
Targ: 625.0DP Tube
y = 579.8636
d = 0.82195
Targ: 5500000.0q Calc
y = 5.411E+06
d = 0.70843
Targ: 5150000.0q Desire
y = 5.106E+06
Targ: -300000.0q (Des -
y = -3.05E+05
0.84011DesirabilityComposite
0.0165
0.0275
0.0143
0.0238
1.50
2.50
0.7430
1.2383
0.3715
0.4953Shell_ID I_Shell_ Tube_ODShell_thBaffle_C
[0.3715] [0.9631] [1.50] [0.0194] [0.0179]
Final: Main Effect Plots
375225
20000
18000
16000
14000
12000
7.54.5
1.238250.74295
20000
18000
16000
14000
12000
0.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for Weight_HEData Means
375225
10000000
8000000
6000000
4000000
7.54.5
1.238250.74295
10000000
8000000
6000000
4000000
0.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for DP ShellData Means
375225
2400
1800
1200
600
07.54.5
1.238250.74295
2400
1800
1200
600
00.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for DP TubeData Means
375225
7000000
6000000
5000000
40000007.54.5
1.238250.74295
7000000
6000000
5000000
40000000.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for q calcData Means
375225
5500000
5250000
5000000
4750000
45000007.54.5
1.238250.74295
5500000
5250000
5000000
4750000
45000000.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for q desiredData Means
375225
1000000
0
-1000000
-2000000
7.54.5
1.238250.74295
1000000
0
-1000000
-2000000
0.02381250.0142875
mdot_shell
Mean
Tube_len
Shell_ID Tube_OD
Main Effects Plot for q (des - calc)Data Means
Final: Pareto Charts
BC
D
C
B
302520151050
Term
Standardized Effect
2.20
B Tube_lenC Shell_IDD Tube_OD
Factor Name
Pareto Chart of the Standardized Effects(response is Weight_HE, Alpha = 0.05)
Shell_ID
Tube_len
Tube_OD
mdot_shell
76543210
Term
Standardized Effect
2.201
Pareto Chart of the Standardized Effects(response is DP Shell, Alpha = 0.05)
Tube_len
Tube_OD
181614121086420
Term
Standardized Effect
2.16
Pareto Chart of the Standardized Effects(response is DP Tube, Alpha = 0.05)
CD
AD
C
A
BD
D
B
80706050403020100
Term
Standardized Effect
2.31
A mdot_shellB Tube_lenC Shell_IDD Tube_OD
Factor Name
Pareto Chart of the Standardized Effects(response is q (des - calc), Alpha = 0.05)
AC
BCD
ABD
BC
AB
CD
AD
C
A
BD
D
B
300250200150100500
Term
Standardized Effect
3.2
A mdot_shellB Tube_lenC Shell_IDD Tube_OD
Factor Name
Pareto Chart of the Standardized Effects(response is q (des - calc), Alpha = 0.05)
Final Variables Calculated
• Desired/Calculated Heat Transfer Rate = 1.00• Overall System Weight = 14382.27 kg• Tube-side Pressure Drop = 417.46 Pa• Shell-side Pressure Drop = 3092917.05 Pa