氏名　KAEWPRADAP AMORNRAT

学位の種類　博士（工学）
学位記番号　甲第489号
学位授与の日付　平成20年12月31日
学位論文題目　Effects of the heat loss and activation energy on the intrinsic instability of premixed flames　（予混合火炎の固有不安定性に与える熱損失と活性化エネルギーの効果）
論文審査委員
　主査　教授　門脇　敏
　副査　教授　増田　渉
　副査　教授　青木　和夫
　副査　准教授　鈴木　正太郎
　副査　准教授　山田　昇

• 論文目次
• 論文要旨
• 論文審査の結果の要旨

［平成20（2008）年度博士論文題名一覧］ ［博士論文題名一覧］に戻る．

Chapter 1　Introduction　p.1
　1.1　General　p.1
　1.2　Literature review　p.2
　1.2.1　Distribution of copy cutter length and tail void　p.2
　1.2.2　Direction control of shield machine　p.3
　1.3　Objective of this study　p.5
　1.4　organization of this research work　p.5
Chapter 2　Mechanized shield tunneling work　p.7
　2.1　Shield tunneling works　p.7
　2.1.1　General aspect of shield tunneling method　p.7
　2.1.2　Shield tunneling machinery and applicable soil types　p.8
　2.1.3　Ground responses caused by shield tunneling　p.10
　2.2　Shield tunneling control system　p.17
　2.2.1　Control system for face stabilization　p.18
　2.2.2　Control system for computation amount of excavated soil volume　p.23
　2.2.3　Back filling control　p.23
　2.2.4　Tail sealed control　p.24
　2.2.5　Shield directional control system　p.25
Chapter 3　Simplified calculation method of overcutting space by in-situ data　p.28
　3.1　Characteristics of in-situ data　p.28
　3.2　Analysis procedure　p.29
　3.2.1　Copy cutter length　p.29
　3.2.1.1　Extension / shrinkage angle　p.29
　3.2.1.2　Circumferential distribution of CC length　p.30
　3.2.1.3　Copy cutter length　p.31
　3.2.2　Thickness of tail void　p.32
　3.2.2.1　Relation of segment and initial excavation area　p.32
　3.2.2.2　thickness of tail void　p.32
　3.2.3　Volume of tail void　p.34
　3.2.3.1　Excavation area　p.34
　3.2.3.2　Volume ot tail void　p.38
　3.3　Analysis results and verification　p.38
　3.3.1　Assumptions in calculation　p.38
　3.3.2　Test site description　p.39
　3.3.3　Distribution of copy cutter length　p.45
　3.3.4　Distribution of tail void　p.45
　3.3.5　Relation among deviation of segment, deviation of cutter face and tail void　p.46
　3.3.5.1　Vertical deviation　p.46
　3.3.5.2　Horizontal deviation　p.49
　3.3.6　Theoretical volume of tail void　p.50
　3.3.6.1　Theoretical excavation volume, actual excavation volume, and mcking rate　p.50
　3.3.6.1　Theoretical volume of tail void, actual grouting volume, and grouting rate　p.55
　3.3　Summary　p.61
Chapter 4　Distribution of overcutting space by Simulated Shield Behavior　p.63
　4.1　Analysis procedure　p.63
　4.2　Analysis results and verification　p.64
　4.2.1　Simulation results of shield behavior　p.64
　4.2.1.1　Trace of shield　p.64
　4.2.1.2　Shield behavior　p.64
　4.2.1.3　Force and moment　p.64
　4.2.2　Distribution of copy cutter length　p.70
　4.2.3　Vertical deviation of cutter face - segment　p.71
　4.2.4　Horizontal deviation of cutter face - segment　p.72
　4.2.5　Distribution of tail void　p.75
　4.3　Summary　p.77
Chapter 5　Analysis of articulation angle and copy cutter length on 3-D tunnel alighment　p.78
　5.1　General　p.78
　5.2　Assumption　p.78
　5.3　Coordinate system　p.80
　5.3.1　Definition　p.80
　5.3.2　Coordinate transformation　p.81
　5.4　Tunnel alighment description　p.81
　5.4.1　Spatial curve　p.81
　5.4.2　Discretization and interpolation　p.84
　5.5　Articulation angle　p.85
　5.6　Classification of crease types　p.89
　5.6.1　Machine type　p.89
　5.6.2　Operation rules at curve　p.92
　5.6.3　Operation rules around BC　p.92
　5.6.4　Operation rules around EC　p.92
　5.7　Calculation method for articulation angle　p.95
　5.7.1　Type 1　p.95
　5.7.2　Type 2　p.98
　5.7.3　Type 3　p.100
　5.8　Calculation method for copy cutter length　p.101
　5.9　Application on different tunnel alignments　p.105
　5.9.1　Machine type　p.105
　5.9.2　Alignment　p.105
　5.9.3　Type1: L1 is max　p.108
　5.9.3.1　Calculation results　p.108
　5.9.3.2　Examination　p.109
　5.9.4　Type2: LCSE is max　p.111
　5.9.4.1　Calculation results　p.111
　5.9.4.2　Examination　p.111
　5.9.5　Type3: L2 is max　p.112
　5.9.5.1　Calculation results　p.112
　5.9.5.2　Examination　p.112
Chapter 6　Conclusions and recommendations　p.131
　6.1　Conclusions　p.131
　6.2　Recommendations for further studies　p.132
REFERENCES　p.133
APPENDIX A　ALINGNMENT OF SHIELD TUNNEL　p.136
　A.1　Circular curve　p.136
　A.2　Transition curve　p.137
　A.2.1　Clothoid curve　p.137
　A.2.2　Parabolic curve　p.140

The effects of the heat loss on the burning velocity of cellular premixed flames were studied by two-dimensional unsteady calculations of reactive flows based on the compressible Navier-Stokes equation. Hydrodynamic and diffusive?thermal instabilities were taken into account as contributing to the intrinsic instability of premixed flames. Moreover, the heat-loss effects on the chaotic behavior of cellular premixed flames generated by intrinsic instability were also studied. The unstable behavior of cellular flames appeared at low Lewis numbers and became stronger as the heat-loss parameter increased. Furthermore, the time series analysis on the burning-velocity fluctuation was performed. The attractor and correlation dimension were obtained to study the characteristics of the chaotic behavior of cellular premixed flames. The characteristics depended strongly on the heat-loss parameter and Lewis number, i. e. on intrinsic instability. The results suggested that this study was applicable to the diagnostics of the flame instability. The effects of the activation energy on the intrinsic instability of adiabatic and non-adiabatic premixed flames were also studied. When the Lewis number was unity, the activation energy had significant effects on the instability of adiabatic flames. In non-adiabatic flames, the growth rate and burning velocity decreased as the activation energy increased, because the reduction of temperature at the flame front had a great influence on the flame instability at large activation energies. When the Lewis number was lower than unity, the activation energy had much effect on both adiabatic and non-adiabatic flames. As the activation energy increased, the growth rate and burning velocity increased drastically, because of the increase of the Zeldovich number. In addition, the unstable behavior of cellular-flame fronts was observed at large activation energies. When the Lewis number was higher than unity, on the other hand, the growth rate and burning velocity decreased as the activation energy increased. This was because that the stabilizing influence of diffusive-thermal effects became larger. The obtained results showed that the activation energy played an important role in the intrinsic instability of adiabatic and non-adiabatic premixed flames.
　Moreover, the flame instability at sufficiently low activation energies was also studied. When the Lewis number was unity, as the activation energy decreased, the growth rate decreased slightly. The mean value of the local burning velocity was almost unity. When the Lewis number was lower than unity, the growth rate decreased and the unstable range narrowed by decreasing the activation energy, which was due to the decrease of diffusive-thermal instability. The mean value of the local burning velocity was slightly larger than unity and became near unity as the activation energy decreased. When the Lewis number was higher than unity, as the activation energy decreased, the growth rate increased and the unstable range widened. The burning velocity did not vary with time. The mean value of the local burning velocity was slightly smaller than unity. The dependence of the growth rate and burning velocity on the Lewis number became drastically weaker at sufficiently low activation energies.
　The obtained results showed that the heat-loss effects on the chaotic behavior were applicable to the diagnostics of the flame instability, and that the activation energy played an important role in the intrinsic instability of adiabatic and non-adiabatic premixed flames.

本論文は、「Effects of the heat loss and activation energy on the intrinsic instability of premixed flames（予混合火炎の固有不安定性に与える熱損失と活性化エネルギーの効果）」と題し、6章より構成されている。
　第1章「Introduction（緒論）」では、予混合火炎の固有不安定性に関する従来の研究の概要を示すとともに、本研究の目的と範囲を述べている。
　第2章「Numerical simulation of premixed combustion（予混合燃焼の数値シミュレーション）」では、本数値解析で用いた基礎方程式と計算手段について記述すると共に、カオス時系列解析について説明している。そして、本研究では固有不安定性の要因として、熱膨張による流体力学的効果と、物質拡散と熱伝導の相互作用による拡散・熱的効果を考慮することを述べている。
　第3章「Heat-loss effects on the chaotic behavior of cellular premixed flames generated by intrinsic instability（固有不安定性に起因するセル状予混合火炎のカオス的挙動における熱損失の効果）」では、増幅率と波数の関係を示す分散関係、固有不安定性に起因するセル状火炎の形成過程、およびセル状火炎の燃焼速度の時間履歴を求めており、それらに及ぼす熱損失の効果を明確にしている。さらに、燃焼速度の時系列を対象としたカオス解析が遂行され、それが火炎不安定性の診断に有用であることを示している。
　第4章「Activation-energy effects on the intrinsic instability of adiabatic and non-adiabatic premixed flames（断熱・非断熱予混合火炎の固有不安定性における活性化エネルギーの効果）」では、断熱・非断熱予混合火炎を対象として、分散関係、セル状火炎、および燃焼速度を求めており、それらに及ぼす活性化エネルギーの効果を明らかにしている。
　第5章「Flame instability at sufficiently low activation energies（充分低い活性化エネルギーにおける火炎の不安定性）」では、反応速度の活性化エネルギーが充分低い条件下での火炎の不安定性を調べており、その条件下では拡散・熱的効果が固有不安定性に重要な影響を及ぼさないことを明らかにしている。
　第6章「Conclusions（結論）」では、本数値解析で得られた結果をまとめ、研究全体を総括している。
　以上のように、予混合火炎の固有不安定性に与える熱損失と活性化エネルギーの効果を明らかにしており、得られた知見のレベルは非常に高いものである。
　よって、本論文は工学上及び工業上貢献するところが大きく、博士（工学）の学位論文として十分な価値を有するものと認める。