Numerical Approach To Wood Pyrolysis In Consideration Heat And Mass Transfer And Chemical Reaction
NUMERICAL APPROACH TO WOOD PYROLYSIS IN
CONSIDERATION HEAT AND MASS TRANSFER
AND CHEMICAL REACTION
THESIS
MUHAMMAD IDRIS
117015011/ TM
ENGINEERING FACULTY
UNIVERSITAS SUMATERA UTARA
MEDAN
2014
Universitas Sumatera Utara
NUMERICAL APPROACH TO WOOD PYROLYSIS IN
CONSIDERATION HEAT AND MASS TRANSFER
AND CHEMICAL REACTION
THESIS
Untuk Memperoleh Gelar Magister Teknik Dalam Program Studi Magister
Teknik Mesin Pada Fakultas Teknik Universitas Sumatera Utara
OLEH
MUHAMMAD IDRIS
117015011/ TM
FAKULTAS TEKNIK
UNIVERSITAS SUMATERA UTARA
MEDAN
2014
Universitas Sumatera Utara
LEMBARAN PENGESAHAN
Judul Penelitian
: NUMERICAL
APPROACH
TO
WOOD
PYROLYSIS IN CONSIDERATION HEAT AND
MASS
TRANSFER
AND
CHEMICAL
REACTION
Nama Mahasiswa
: MUHAMMAD IDRIS
Nomor Pokok
: 117015011
Program Studi
: MAGISTER TEKNIK MESIN
Menyetujui :
Komisi Pembimbing
Prof. Hiroomi Homma
( Ketua )
Dr. Eng. Himsar Ambarita, ST, MT
( Anggota )
Ketua Program Studi
Dekan Fakultas Teknik
Dr. Eng. Ir. Indra, MT
Prof. Dr. Ir. Bustami Syam, MSME
Universitas Sumatera Utara
Tanggal Lulus : 07 Juni 2014
Universitas Sumatera Utara
Telah diuji pada
Tanggal :
PANITIA PENGUJI TESIS
Ketua
: Prof. Dr. Ir. Farel H. Napitupulu, DEA
Anggota
: 1. Dr. Eng. Himsar Ambarita, ST, MT
2. Prof. Farel. H. Napitupulu, DEA
3. Prof. Dr. Ir. Ilmi Abdullah, M.Sc
3. Dr. Eng. Ir. Taslim, MT
Universitas Sumatera Utara
ABSTRACK
Climate change, global warming, and energy crisis are critical issues to be
solved urgently in a global framework. Alternative energy and renewable energy
technologies must be quickly developed to be substituted for fossil fuels like oil,
gases, and coal. USA, UE, and Japan invested huge budgets to develop biomass
renewable energy technology. Their target is to develop commercial base large-scaled
plant. On the other hand, in developing countries, especially in rural areas, people
who can access electricity is still less than 70%, To decelerate or prevent global
warming, and improve electrification in rural areas, a new technology for wood
pyrolysis, which requires low manufacturing cost and less maintenance, and of which
gases are directly applicable to gas engine generator, was developed by the previous
work. This work aims at understanding pyrolysis process in the pre-vacuum chamber
in more detail and thus improving the plant performance, and carries out numerical
analysis on the pyrolysis process taking into account fluid dynamics and chemical
reaction inside the pre-vacuum chamber. The numerical results provide useful
information to understand the pyrolysis process and to improve the plant
performance.
Keywords: pyrolysis, pre-vacuum
sublimation, ANSYS Fluent
chamber,
chemical
reaction,
volatile
Universitas Sumatera Utara
ABSTRAK
Perubahan iklim, pemanasan global, dan krisis energi merupakan masalah
yang sangat mendesak untuk segera diselesaikan dalam global framework. Teknologi
energi terbarukan dan energi alternatif ini harus segera dikembangkan untuk
menggantikan bahan bakar fosil seperti minyak, gas, dan batu bara. USA, UE, dan
Jepang telah meninvestasikan anggaran dalam jumlah yang sangat besar untuk
mengembangkan teknologi energi terbarukan biomassa . Target mereka adalah untuk
mengembangkan basis pabrik komersial dalam skala besar. Di sisi lain, di negara
berkembang, terutama di daerah pedesaan, masalah yang dialami oleh masyarakat
adalah akses listrik masih kurang dari 70 persen, oleh karena itu untuk memperlambat
atau mencegah pemanasan global, dan meningkatkan elektrifikasi di wilayah
pedesaan, sebuah teknologi baru untuk pirolisis kayu, dengan biaya dan teknologi
yang rendah, sedikit biaya perawatan, dan gas yang diperoleh secara langsung bisa
diterapkan pada mesin generator berbahan bakar gas, dimana telah dikembangkan
oleh pekerjaan sebelumnya. Penelitian ini bertujuan untuk memahami proses pirolisis
di dalam pre-vacuum chamber secara lebih rinci, meningkatkan kinerja peralatan, dan
melakukan analisis numerik pada proses pirolisis dengan mempertimbangkan
dinamika fluida dan reaksi kimia di dalam pre-vacuum chamber. Hasil numerik
memberikan informasi yang berguna untuk memahami proses pirolisis dan untuk
meningkatkan kinerja perlatan.
Kata kunci: pyrolysis, pre-vacuum chamber, chemical reaction, volatile
sublimation, ANSYS Fluent
Universitas Sumatera Utara
DAFTAR ISI
Halaman
ABSTRACT …………….………………………………………………………
i
ABSTRAK ..……………………………………………………………………..
ii
ACKNOWLEDGMENT ……………………..…………………………………
iii
CURRICULUM VITAE ............………………………………………………..
v
CONTENTS ..…………………………………..……………………………….
viii
TABLE CONTENTS …………………………………..………………………..
xi
FIGURE CONTENTS…………………………………..……………………….
xii
NOTATION CONTENTS ………………………………………………………
xiv
1
INTRODUCTION .....……………………………..…………………….
1.1. Background ..........……………………………………………….
1.1.1. Global Warming ..............................................................
1.1.2. Energy Crisis ....................................................................
1.1.3. Indonesia Energy Conditions ...........................................
1.1.4. Renewable Energy Status in Indonesia ............................
1.1.5. Biomass Potential in Indonesia ........................................
1.2. Limitation of Problem ……………………...…………………….
1.3. Research Objective .…….………………………………………..
1
1
2
4
7
9
12
15
15
2
REVIEW OF LITERATURE ..………………………...…………….......
2.1. Reviews on Previous Woods Pyrolysis Researches ..…….………
2.1.1. Biomass Conversion Processes.........................................
2.1.2. Thermochemical Reactions in Wood Pyrolysis ...............
2.1.3. Experimental Works of Wood Pyrolysis .........................
2.1.4. Kinetic Models in Biomass Pyrolysis ..............................
2.1.5. Numerical Analysis of pyrolysis ......................................
2.1.5.1. Governing Equations in CDF ..........................
2.1.5.2. Assumptions of Numerical Analysis ..............
17
17
17
20
23
24
28
29
31
3
EXPERIMENTAL WORK ........................................................................
33
Universitas Sumatera Utara
3.1.
3.2.
3.3.
4
5
Place and Time ...............................................................................
Material and Method Used for Experiment ...................................
3.2.1. Feedstock of Pyrolysis .....................................................
3.2.2. Experimental Equipment .................................................
3.2.3. Temperature Measurement ..............................................
3.2.4. Experimental Method ......................................................
3.2.5. Measured Results .............................................................
3.2.5.1. Temperature ....................................................
3.2.5.2. Pressure ...........................................................
3.2.5.3. Pyrolysis Yield ................................................
Conclusions ....................................................................................
NUMERICAL ANALYSIS ON THERMAL CONDUCTION IN PREVACUUM CHAMBER .............................................................................
4.1. Introduction ....................................................................................
4.2. Numerical Analysis Method ..........................................................
4.2.1. Thermal Conduction Model .............................................
4.2.2. Heating Condition of Wood Stove Furnace .....................
4.2.3. Model of Feedstock Charge .............................................
4.2.4. Mesh Model .....................................................................
4.3. Numerical Result and Discussion ..................................................
4.3.1. Synoptic View of Temperature ........................................
4.3.2. Comparison between Numerical and Experimental
Results inside Chamber ...................................................
4.3.3. Temperature Distribution inside Chamber.......................
4.3.4. Temperature Distribution at 400 Seconds .......................
4.3.5. Temperature Distribution at 800 Seconds .......................
4.3.6. Temperature Distribution at 1200 Seconds ....................
4.4. Conclusions ....................................................................................
NUMERICAL ANALYSIS ON WOOD PYROLYSIS IN PREVACUUM CHAMBER .............................................................................
5.1. Introduction ....................................................................................
5.2. Modelling of Pre-Vacuum Chamber Pyrolysis ..............................
5.2.1. Mesh model of Pre-Vacuum Chamber ............................
5.2.1.1. Boundary Conditions of Pre-Vacuum
Chamber ..........................................................
5.2.1.2. Fluent Solution Options ..................................
5.2.2. Chemical kinetics .............................................................
5.2.3. Chemical Formula and Reaction ......................................
5.2.4. Volatilization ...................................................................
5.2.5. Endothermic Reaction ......................................................
33
33
33
34
35
36
37
37
39
39
40
42
42
42
42
45
46
47
47
47
49
52
52
53
54
56
57
57
60
60
62
63
65
67
70
71
Universitas Sumatera Utara
5.3.
Numerical Results ..........................................................................
5.3.1. Pressure Evolution with Time ..........................................
5.3.2. Temperature in Pre-Vacuum Chamber ............................
5.3.3. Decomposition of Volatile Gas ........................................
Discussion ......................................................................................
5.4.1. Volatile Sublimation ........................................................
5.4.2. Comparison of Numerical Analysis Results by Thermal
Conduction and Heat Mass Transfer Analysis ................
Conclusions ....................................................................................
72
73
74
75
77
77
SUMMARY AND RECOMMENDATION ..............................................
6.1. Summary ........................................................................................
6.2. Recommendation ...........................................................................
82
82
84
BIBLIOGRAPHY .................................................................................................
86
APPENDIX ...........................................................................................................
91
5.4.
5.5.
6
77
79
Universitas Sumatera Utara
TABLE CONTENTS
Number
Title
Page
1.1.
Renewable Energy Potential in Indonesia ..............................
12
1.2.
Energy Potential of Biomass by Region in Indonesia ............
13
2.1.
Typical Proximate and Ultimate Analyses of Dry Wood by
Weight (%) ..............................................................................
24
3.1.
Pyrolysis Yield ........................................................................
40
4.1.
45
5.1.
Material
Model
........................................................................
Material properties used for numerical analysis .....................
5.2.
Arrhenius type of chemical kinetics parameters .....................
67
5.3.
Calculation
of
..............................................
69
volatile
elements
61
Universitas Sumatera Utara
FIGURE CONTENTS
Number
Title
Page
1.1.
Worlds Energy Consumption ...........................................
5
1.2.
Energy consumption per capita (1990, 2000, 2010 and
2030) ................................................................................
5
1.3.
World Oil Production .......................................................
6
1.4.
The Energy Consumption in 2000 - 2010 by Type ..........
8
1.5.
Projection of total final energy demand by energy
sector ...............................................................................
9
1.6.
Current Energy Mix versus Future Energy Goals ............
10
2.1.
Chart of the Biomass Conversion Process .......................
17
2.2.
The process of gasification and pyrolysis ........................
20
2.3.
Thermal stability main components of wood ...................
21
2.4.
Stage Process Of Thermal Decompose Wood
Component .......................................................................
22
3.1.
Illustration of a pyrolysis pilot plant for this study ..........
34
3.2.
Additional devices ...........................................................
35
3.3.
Temperature measurement ...............................................
36
3.4.
Temperature as a function of time ...................................
38
3.5.
Chamber pressure as a function of time ...........................
39
4.1.
Chamber model ................................................................
43
4.2.
ANSYS Analysis Model ..................................................
44
4.3.
Heating function ...............................................................
46
4.4.
Meshing model .................................................................
47
4.5.
Temperature contour at 1200 second (20 minutes) ..........
48
4.6.
Temperature (T1) at the chamber bottom ........................
49
Universitas Sumatera Utara
4.7.
4.8.
Comparison between temperatures (T2) near the
chamber top ......................................................................
Temperature at flange top surface ....................................
50
51
4.9.
Temperature distribution at 400 second ...........................
53
4.10.
Temperature distributions at 800 seconds ........................
54
4.11.
Temperature distribution at 1200 second .........................
55
5.1.
Fluent analysis model ......................................................
61
5.2.
Boundary Condition of Pre-Vacuum Chamber ................
63
5.3.
Pyrolysis kinetics used for this numerical analysis ..........
67
5.4.
Pressure evolution with time in pre-vacuum chamber .....
73
5.5.
Time evolution of volume-average temperaturein ...........
75
5.6.
Mole Concentration of each Species as a function of
time ..................................................................................
76
Comparison of Numerical Analysis Results by Thermal
Conduction and Heat Mass Transfer Analysis .................
79
5.7.
Universitas Sumatera Utara
CONSIDERATION HEAT AND MASS TRANSFER
AND CHEMICAL REACTION
THESIS
MUHAMMAD IDRIS
117015011/ TM
ENGINEERING FACULTY
UNIVERSITAS SUMATERA UTARA
MEDAN
2014
Universitas Sumatera Utara
NUMERICAL APPROACH TO WOOD PYROLYSIS IN
CONSIDERATION HEAT AND MASS TRANSFER
AND CHEMICAL REACTION
THESIS
Untuk Memperoleh Gelar Magister Teknik Dalam Program Studi Magister
Teknik Mesin Pada Fakultas Teknik Universitas Sumatera Utara
OLEH
MUHAMMAD IDRIS
117015011/ TM
FAKULTAS TEKNIK
UNIVERSITAS SUMATERA UTARA
MEDAN
2014
Universitas Sumatera Utara
LEMBARAN PENGESAHAN
Judul Penelitian
: NUMERICAL
APPROACH
TO
WOOD
PYROLYSIS IN CONSIDERATION HEAT AND
MASS
TRANSFER
AND
CHEMICAL
REACTION
Nama Mahasiswa
: MUHAMMAD IDRIS
Nomor Pokok
: 117015011
Program Studi
: MAGISTER TEKNIK MESIN
Menyetujui :
Komisi Pembimbing
Prof. Hiroomi Homma
( Ketua )
Dr. Eng. Himsar Ambarita, ST, MT
( Anggota )
Ketua Program Studi
Dekan Fakultas Teknik
Dr. Eng. Ir. Indra, MT
Prof. Dr. Ir. Bustami Syam, MSME
Universitas Sumatera Utara
Tanggal Lulus : 07 Juni 2014
Universitas Sumatera Utara
Telah diuji pada
Tanggal :
PANITIA PENGUJI TESIS
Ketua
: Prof. Dr. Ir. Farel H. Napitupulu, DEA
Anggota
: 1. Dr. Eng. Himsar Ambarita, ST, MT
2. Prof. Farel. H. Napitupulu, DEA
3. Prof. Dr. Ir. Ilmi Abdullah, M.Sc
3. Dr. Eng. Ir. Taslim, MT
Universitas Sumatera Utara
ABSTRACK
Climate change, global warming, and energy crisis are critical issues to be
solved urgently in a global framework. Alternative energy and renewable energy
technologies must be quickly developed to be substituted for fossil fuels like oil,
gases, and coal. USA, UE, and Japan invested huge budgets to develop biomass
renewable energy technology. Their target is to develop commercial base large-scaled
plant. On the other hand, in developing countries, especially in rural areas, people
who can access electricity is still less than 70%, To decelerate or prevent global
warming, and improve electrification in rural areas, a new technology for wood
pyrolysis, which requires low manufacturing cost and less maintenance, and of which
gases are directly applicable to gas engine generator, was developed by the previous
work. This work aims at understanding pyrolysis process in the pre-vacuum chamber
in more detail and thus improving the plant performance, and carries out numerical
analysis on the pyrolysis process taking into account fluid dynamics and chemical
reaction inside the pre-vacuum chamber. The numerical results provide useful
information to understand the pyrolysis process and to improve the plant
performance.
Keywords: pyrolysis, pre-vacuum
sublimation, ANSYS Fluent
chamber,
chemical
reaction,
volatile
Universitas Sumatera Utara
ABSTRAK
Perubahan iklim, pemanasan global, dan krisis energi merupakan masalah
yang sangat mendesak untuk segera diselesaikan dalam global framework. Teknologi
energi terbarukan dan energi alternatif ini harus segera dikembangkan untuk
menggantikan bahan bakar fosil seperti minyak, gas, dan batu bara. USA, UE, dan
Jepang telah meninvestasikan anggaran dalam jumlah yang sangat besar untuk
mengembangkan teknologi energi terbarukan biomassa . Target mereka adalah untuk
mengembangkan basis pabrik komersial dalam skala besar. Di sisi lain, di negara
berkembang, terutama di daerah pedesaan, masalah yang dialami oleh masyarakat
adalah akses listrik masih kurang dari 70 persen, oleh karena itu untuk memperlambat
atau mencegah pemanasan global, dan meningkatkan elektrifikasi di wilayah
pedesaan, sebuah teknologi baru untuk pirolisis kayu, dengan biaya dan teknologi
yang rendah, sedikit biaya perawatan, dan gas yang diperoleh secara langsung bisa
diterapkan pada mesin generator berbahan bakar gas, dimana telah dikembangkan
oleh pekerjaan sebelumnya. Penelitian ini bertujuan untuk memahami proses pirolisis
di dalam pre-vacuum chamber secara lebih rinci, meningkatkan kinerja peralatan, dan
melakukan analisis numerik pada proses pirolisis dengan mempertimbangkan
dinamika fluida dan reaksi kimia di dalam pre-vacuum chamber. Hasil numerik
memberikan informasi yang berguna untuk memahami proses pirolisis dan untuk
meningkatkan kinerja perlatan.
Kata kunci: pyrolysis, pre-vacuum chamber, chemical reaction, volatile
sublimation, ANSYS Fluent
Universitas Sumatera Utara
DAFTAR ISI
Halaman
ABSTRACT …………….………………………………………………………
i
ABSTRAK ..……………………………………………………………………..
ii
ACKNOWLEDGMENT ……………………..…………………………………
iii
CURRICULUM VITAE ............………………………………………………..
v
CONTENTS ..…………………………………..……………………………….
viii
TABLE CONTENTS …………………………………..………………………..
xi
FIGURE CONTENTS…………………………………..……………………….
xii
NOTATION CONTENTS ………………………………………………………
xiv
1
INTRODUCTION .....……………………………..…………………….
1.1. Background ..........……………………………………………….
1.1.1. Global Warming ..............................................................
1.1.2. Energy Crisis ....................................................................
1.1.3. Indonesia Energy Conditions ...........................................
1.1.4. Renewable Energy Status in Indonesia ............................
1.1.5. Biomass Potential in Indonesia ........................................
1.2. Limitation of Problem ……………………...…………………….
1.3. Research Objective .…….………………………………………..
1
1
2
4
7
9
12
15
15
2
REVIEW OF LITERATURE ..………………………...…………….......
2.1. Reviews on Previous Woods Pyrolysis Researches ..…….………
2.1.1. Biomass Conversion Processes.........................................
2.1.2. Thermochemical Reactions in Wood Pyrolysis ...............
2.1.3. Experimental Works of Wood Pyrolysis .........................
2.1.4. Kinetic Models in Biomass Pyrolysis ..............................
2.1.5. Numerical Analysis of pyrolysis ......................................
2.1.5.1. Governing Equations in CDF ..........................
2.1.5.2. Assumptions of Numerical Analysis ..............
17
17
17
20
23
24
28
29
31
3
EXPERIMENTAL WORK ........................................................................
33
Universitas Sumatera Utara
3.1.
3.2.
3.3.
4
5
Place and Time ...............................................................................
Material and Method Used for Experiment ...................................
3.2.1. Feedstock of Pyrolysis .....................................................
3.2.2. Experimental Equipment .................................................
3.2.3. Temperature Measurement ..............................................
3.2.4. Experimental Method ......................................................
3.2.5. Measured Results .............................................................
3.2.5.1. Temperature ....................................................
3.2.5.2. Pressure ...........................................................
3.2.5.3. Pyrolysis Yield ................................................
Conclusions ....................................................................................
NUMERICAL ANALYSIS ON THERMAL CONDUCTION IN PREVACUUM CHAMBER .............................................................................
4.1. Introduction ....................................................................................
4.2. Numerical Analysis Method ..........................................................
4.2.1. Thermal Conduction Model .............................................
4.2.2. Heating Condition of Wood Stove Furnace .....................
4.2.3. Model of Feedstock Charge .............................................
4.2.4. Mesh Model .....................................................................
4.3. Numerical Result and Discussion ..................................................
4.3.1. Synoptic View of Temperature ........................................
4.3.2. Comparison between Numerical and Experimental
Results inside Chamber ...................................................
4.3.3. Temperature Distribution inside Chamber.......................
4.3.4. Temperature Distribution at 400 Seconds .......................
4.3.5. Temperature Distribution at 800 Seconds .......................
4.3.6. Temperature Distribution at 1200 Seconds ....................
4.4. Conclusions ....................................................................................
NUMERICAL ANALYSIS ON WOOD PYROLYSIS IN PREVACUUM CHAMBER .............................................................................
5.1. Introduction ....................................................................................
5.2. Modelling of Pre-Vacuum Chamber Pyrolysis ..............................
5.2.1. Mesh model of Pre-Vacuum Chamber ............................
5.2.1.1. Boundary Conditions of Pre-Vacuum
Chamber ..........................................................
5.2.1.2. Fluent Solution Options ..................................
5.2.2. Chemical kinetics .............................................................
5.2.3. Chemical Formula and Reaction ......................................
5.2.4. Volatilization ...................................................................
5.2.5. Endothermic Reaction ......................................................
33
33
33
34
35
36
37
37
39
39
40
42
42
42
42
45
46
47
47
47
49
52
52
53
54
56
57
57
60
60
62
63
65
67
70
71
Universitas Sumatera Utara
5.3.
Numerical Results ..........................................................................
5.3.1. Pressure Evolution with Time ..........................................
5.3.2. Temperature in Pre-Vacuum Chamber ............................
5.3.3. Decomposition of Volatile Gas ........................................
Discussion ......................................................................................
5.4.1. Volatile Sublimation ........................................................
5.4.2. Comparison of Numerical Analysis Results by Thermal
Conduction and Heat Mass Transfer Analysis ................
Conclusions ....................................................................................
72
73
74
75
77
77
SUMMARY AND RECOMMENDATION ..............................................
6.1. Summary ........................................................................................
6.2. Recommendation ...........................................................................
82
82
84
BIBLIOGRAPHY .................................................................................................
86
APPENDIX ...........................................................................................................
91
5.4.
5.5.
6
77
79
Universitas Sumatera Utara
TABLE CONTENTS
Number
Title
Page
1.1.
Renewable Energy Potential in Indonesia ..............................
12
1.2.
Energy Potential of Biomass by Region in Indonesia ............
13
2.1.
Typical Proximate and Ultimate Analyses of Dry Wood by
Weight (%) ..............................................................................
24
3.1.
Pyrolysis Yield ........................................................................
40
4.1.
45
5.1.
Material
Model
........................................................................
Material properties used for numerical analysis .....................
5.2.
Arrhenius type of chemical kinetics parameters .....................
67
5.3.
Calculation
of
..............................................
69
volatile
elements
61
Universitas Sumatera Utara
FIGURE CONTENTS
Number
Title
Page
1.1.
Worlds Energy Consumption ...........................................
5
1.2.
Energy consumption per capita (1990, 2000, 2010 and
2030) ................................................................................
5
1.3.
World Oil Production .......................................................
6
1.4.
The Energy Consumption in 2000 - 2010 by Type ..........
8
1.5.
Projection of total final energy demand by energy
sector ...............................................................................
9
1.6.
Current Energy Mix versus Future Energy Goals ............
10
2.1.
Chart of the Biomass Conversion Process .......................
17
2.2.
The process of gasification and pyrolysis ........................
20
2.3.
Thermal stability main components of wood ...................
21
2.4.
Stage Process Of Thermal Decompose Wood
Component .......................................................................
22
3.1.
Illustration of a pyrolysis pilot plant for this study ..........
34
3.2.
Additional devices ...........................................................
35
3.3.
Temperature measurement ...............................................
36
3.4.
Temperature as a function of time ...................................
38
3.5.
Chamber pressure as a function of time ...........................
39
4.1.
Chamber model ................................................................
43
4.2.
ANSYS Analysis Model ..................................................
44
4.3.
Heating function ...............................................................
46
4.4.
Meshing model .................................................................
47
4.5.
Temperature contour at 1200 second (20 minutes) ..........
48
4.6.
Temperature (T1) at the chamber bottom ........................
49
Universitas Sumatera Utara
4.7.
4.8.
Comparison between temperatures (T2) near the
chamber top ......................................................................
Temperature at flange top surface ....................................
50
51
4.9.
Temperature distribution at 400 second ...........................
53
4.10.
Temperature distributions at 800 seconds ........................
54
4.11.
Temperature distribution at 1200 second .........................
55
5.1.
Fluent analysis model ......................................................
61
5.2.
Boundary Condition of Pre-Vacuum Chamber ................
63
5.3.
Pyrolysis kinetics used for this numerical analysis ..........
67
5.4.
Pressure evolution with time in pre-vacuum chamber .....
73
5.5.
Time evolution of volume-average temperaturein ...........
75
5.6.
Mole Concentration of each Species as a function of
time ..................................................................................
76
Comparison of Numerical Analysis Results by Thermal
Conduction and Heat Mass Transfer Analysis .................
79
5.7.
Universitas Sumatera Utara