論文提要內容：
翼胴合一（BWB）是最經濟的飛機配置之一，全電動飛機通過減少污染將成為未來的主流。鳥擊一直是航空安全的重大問題，因此在電風扇進風口前發明了錐形的鳥擊防護網。本研究的目的是對全電動 BWB 和防鳥撞網進行空氣動力學分析。在驗證 DLR F6 模型後，用相同的數值模擬工具應用於我們設計的外型。主要研究成果:（1）發明一種具有足夠起飛和巡航推力的全電動涵道風扇，（2）詳細研究了發動機運轉情況下巡航（0.7馬赫和FL280）時BWB的氣動特性，以及(3) 估計其起降場長度。發現我們的防鳥撞網約佔總阻力的 19%，我們的發現將有助於下一代飛機的設計，而未來可能仍需要優化當前的電動涵道風扇發動機和 BWB 配置，因此代表其空氣動力學性能有更大的增長潛力。

Blended-wind-body (BWB) is one of the most economical aircraft configuration, and all-electric aircraft will be the future mainstream by reducing pollutions. Bird strikes have always been a major aviation safety problem, so a cone-shaped bird-strike prevention net in front of electric fan inlet is invented. Objectives of this study are the aerodynamic analyses of all-electric powered BWB and bird strike resistance net. After validation of DLR F6 model, same numerical simulation tools then applied to our designated configurations. Major research findings are (1) invention of an all-electric ducted-fan with enough thrust produced for take-off and cruise, (2) detailed investigation of BWB’s aerodynamic characteristics during cruise (0.7 Mach and FL280) with power on situation, and (3) estimation of its take-off and landing field lengths. It is found that our bird strike resistance net account for about 19% of total drag, and our findings will be helpful for next generation aircraft design, while future optimization of current electric ducted-fan engine and BWB configuration might still be needed, thus represent more potential growth in its aerodynamic performance.

Abstract	III
Contents	V
List of Tables	VII
List of Figures	VIII
List of Abbreviations	XIII
List of Symbols	XIV
Chapter 1 Introduction	1
1.1 Motivation	1
1.2 Preparation	3
Chapter 2 Research Background	5
2.1 Variants of BWB Aircraft	5
2.2 Variants of All Electric Powered Aircraft	10
2.3 Bird Strike Resistance Capability	12
2.4 Computational Fluid Dynamics	13
Chapter 3 Numerical Modeling	15
3.1 Geometric Model	17
3.2 Grid Generation	25
3.3 Computation Setup and Boundary Conditions	28
3.4 Governing Equations and Flow Solver	31
3.5 Turbulence Model	33
3.6 Rotating Mechanism	35
Chapter 4 Validation	37
4.1 DLR-F6 Model	37
4.2 Discussion	44
4.3 Grid Convergence Test	45
Chapter 5 Results and Discussion	47
5.1 Simulations of Engine’s Performance	47
5.2 Simulations of BWB’s Performance	56
5.3 Take-off and Landing Runway Lengths of BWB	74
Chapter 6 Conclusions	78
References	80













List of Tables
Table 1 Parameters of engine at sea level.	16
Table 2 Parameters of engine during cruise.	16
Table 3 Parameters of BWB wing geometry.	18
Table 4 Parameters of BWB take-off condition.	29
Table 5 Parameters of BWB cruise flight condition.	29
Table 6 Parameters of DLR-F6 flight condition.	40
Table 7 Parameters of BWB at 0° AoA.	46
Table 8 Parameters of engine at sea level.	48
Table 9 Drag distribution of engine at sea level.	48
Table 10 Engine’s thrust and drag at difference rotation speed.	49
Table 11 Aerodynamic coefficients at different AoA values.	57
 
List of Figures
Figure 1 Genesis of the BWB concept.	7
Figure 2 Interior arrangement of BWB passenger cabin.	8
Figure 3 MAVERIC project’s BWB aircraft.	10
Figure 4 E-FAN X aircraft.	11
Figure 5 Airfoil NASA SC(2)-0518 (left) and NASA SC(2)-0710 (right).	18
Figure 6 The geometry of the BWB in CATIA (front view).	19
Figure 7 The geometry of the BWB in CATIA (top view).	19
Figure 8 Size of the BWB.	19
Figure 9 Twenty blades fan front view (left), fan front view (right).	20
Figure 10 The distribution of fan blade positions.	21
Figure 11 The geometry of each airfoil.	21
Figure 12 The geometry of each airfoil after altered.	22
Figure 13 Sixteen blades fan front view (left), fan front view (right).	23
Figure 14 Geometry of bird strike net (side view).	24
Figure 15 Geometry of bird strike resistance net (front view).	24
Figure 16 Mesh of whole domain.	26
Figure 17 Mesh on sectional plane at the engine centerline.	27
Figure 18 Mesh of engine fan.	27
Figure 19 Mesh of BWB.	28
Figure 20 The computational domain boundary conditions.	30
Figure 21 The electric ducted-fan boundary conditions.	31
Figure 22 Computation iteration flow chart.	33
Figure 23 The rotating disks.	35
Figure 24 The geometry of DLR-F6 .	38
Figure 25 The computational domain of DLR-F6.	38
Figure 26 The boundary conditions of DLR-F6.	39
Figure 27 The distribution of CP and positions.	39
Figure 28 The distribution of Cp on the wing section at η = 0.15 position.	41
Figure 29 The distribution of Cp on the wing section at η = 0.239 position.	41
Figure 30 The distribution of Cp on the wing section at η= 0.331 position.	42
Figure 31 The distribution of Cp on the wing section at η = 0.337 position.	42
Figure 32 The distribution of Cp on the wing section at η =0.514 position.	43
Figure 33 The distribution of Cp on the wing section at η = 0.638 position.	43
Figure 34 The distribution of Cp on the wing section at η =0.847 position.	44
Figure 35 DLR-F6 vorticity contour.	45
Figure 36 Pressure contour of electric engine (side view).	50
Figure 37 Velocity contour of electric engine (side view).	51
Figure 38 Vorticity contour of electric engine (side view).	51
Figure 39 Pressure contour at intake of electric engine (front view).	52
Figure 40 Velocity contour at intake of electric engine (front view).	52
 Figure 41 Vorticity contour at intake of electric engine (front view).	53
Figure 42 Pressure contour at exhaust of electric engine (back view).	53
Figure 43 Velocity contour at exhaust of electric engine (back view).	54
Figure 44 Vorticity contour at exhaust of electric engine (back view).	54
Figure 45 Q-criterion iso-surface of electric engine, Q = 2500 1/s^2(front view)	55
Figure 46 Q-criterion iso-surface of electric engine, Q = 2500 1/s^2(side view).	55
Figure 47 Change of lift coefficient vs. AoA.	58
Figure 48 Change of lift coefficient vs. drag coefficient.	58
Figure 49 Change of L/D vs. AoA.	59
Figure 50 Change of Cm vs. AoA.	59
Figure 51 Lift force caused by each part of the aircraft.	60
Figure 52 Drag force caused by each part of the aircraft.	61
Figure 53 The position of each station on the BWB.	62
Figure 54 The pressure contour at the centerline of fuselage.	62
Figure 55 The pressure contour at centerline of engine.	63
Figure 56 The pressure contour at the wing-body transition location.	63
Figure 57 The pressure contour at the m.a.c. location.	64
Figure 58 The pressure contour at the wingtip location.	64
Figure 59 The velocity contour at the centerline of fuselage.	65
 Figure 60 The velocity contour at centerline of engine.	66
Figure 61 The velocity contour at the wing-body transition location.	66
Figure 62 The velocity contour at the m.a.c. location.	67
Figure 63 The velocity contour at the wingtip location.	67
Figure 64 The velocity contour on the engine (top view).	68
Figure 65 The vorticity contour at the centerline of fuselage.	69
Figure 66 The vorticity contour at centerline of engine.	69
Figure 67 The vorticity contour at the wing-body transition location.	70
Figure 68 The vorticity contour at the m.a.c. location.	70
Figure 69 The vorticity contour at the wingtip location.	71
Figure 70 Q-criterion iso-surface of the BWB (side view), Q = 4900 1/s^2.	72
Figure 71 Q-criterion iso-surface of the BWB (side view), Q = 4900 1/s^2	72
 Figure 72 Q-criterion iso-surface of the BWB (top view), Q = 4900 1/s^2.	73
Figure 73 Vorticity distribution of BWB during 3.5°AoA.	73

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