표제지
목차
기호 및 약어 설명 7
1. 서론 17
2. 수학적 모델 및 解法 20
2.1 氣相지배방정식의 유도 20
2.2 난류 26
2.2.1 난류 모델 26
2.2.2 벽함수 34
2.3 고상 粒子의 지배방정식 38
2.4 난류 반응 45
2.4.1 Eddy breakup 모델 45
2.4.2 엔탈피 벽함수(Wall Function) 49
2.5 離散化방정식 및 TDMA 알고리즘 51
2.6 수치해석 알고리즘 57
3. 응용문제 63
3.1 일차침전조내의 부유고형물질(SS) 농도 예측 63
3.1.1 서론 63
3.1.2 수학적 모델 및 지배방정식 67
3.1.3 경계조건 67
3.1.4 SS의 지배방정식 68
3.1.5 계산 결과 및 토론 71
3.1.6 결론 80
3.2 싸이클론형 후연소로 81
3.2.1 서론 81
3.2.2 수학적 모델 및 지배방정식 82
3.2.3 경계조건 83
3.2.4 계산 결과 및 토론 84
3.2.5 결론 103
3.3 싸이클론형 슬래깅 연소로 104
3.3.1 서론 104
3.3.2 수학적 모델 및 지배방정식 115
3.3.3 경계 조건 116
3.3.4 계산 결과 및 토론 118
3.3.5 결론 153
4. 결론 154
참고문헌 156
Abstract 165
표 목차
Table 2-1 Expressions for Fø and Sø for k- ø turbulence model 32
Table 3-1-1 Turbulent diffusion coefficient(Fø) and source term (SOø) expression for ø 70
Table 3-1-2 SS의 입경 분포에 따른 종발침강속도 73
Table 3-2-1 후연소로 계산에 사용된 표준계산조건 84
Table 3-3-1 Review of pulverized coal-fired comprehensive computer programs and applications 114
Table 3-3-2 슬래깅 연소로에 사용된 실험 및 계산 조건 119
Table 3-3-3 슬래깅 연소로에 사용된 실험 및 계산 조건 121
그림 목차
Fig.2-1 Near a north wall 34
Fig.2-2 Universal velocity distribution law of the wall 36
Fig.2-3 Homogeneous coal-air model 44
Fig.2-4 Schematic diagram of the cartesian grid layout 53
Fig.2-5 Schematic diagram of the cylindrical grid layout 53
Fig.2-6 Schematic diagram of the staggered grid layout 53
Fig.3-1-1 Geometry of the clarifier 66
Fig.3-1-2 Boundary condition employed in the study 68
Fig.3-1-3 Variables of main and staggered points over a solid block 69
Fig.3-1-4 Comparison between present calculation (standard and RNG k- ε model) and experimental calculation data by Stamou et al. 74
Fig.3-1-5 Turbulent viscosity contour plots 75
Fig.3-1-6 Experimental and calculated SS concentration distribution(Stamou et al, 1989) 76
Fig.3-1-7 The prediction of SS concentration distribution of the study 76
Fig.3-1-8 Concentration contour with the change of the overflow rate 77
Fig.3-1-9 Concentration contour with the change of the Schmidt number 78
Fig.3-1-10 Concentration contour for particle size 79
Fig.3-2-1 Schematic diagram of cyclone 83
Fig.3-2-2 Velocity vector, streamline and particle trajectory plots 90
Fig.3-2-3 Comparison of tangential velocity profiles at X=0.4, 0.6, 0.8, 1.0m(R=0.25m, XL=2m, θ=60˚) 91
Fig.3-2-4 Streamline plots for the change of radius(XL=2m, θ=60˚, Vr=28.3m/s, Vθ=49.02m/s) 92
Fig.3-2-5 Comparison of velocity vector plots between R=0.25m and R=0.175m(XL=2m, θ=60˚) 93
Fig.3-2-6 Comparison of tangential velocity profiles at X=0.4, 0.6, 0.8, 1.0m(R=0.175m, XL=2m, θ=60˚) 94
Fig.3-2-7 Comparison of velocity vector plots according to injection angle(XL=2m) 95
Fig.3-2-8 Comparison of streamline plots according to injection angle(XL=2m) 96
Fig.3-2-9 Comparison of velocity vector plots according to injection angle(XL=4m) 97
Fig.3-2-10 Comparison of tangential velocity profiles at X=0.4, 0.6, 0.8, 1.0, 1.2, 1.4m(R=0.175 m, XL=2m, θ=60˚) 98
Fig.3-2-11 Comparison of velocity vector plots between R=0.25m and R=0.175m(XL=4m, θ=60˚) 99
Fig.3-2-12 Streakline plots(XL=4m, θ=60˚) 100
Fig.3-2-13 Comparison of velocity vector plots according to Temperature 500K, 1000K 101
Fig.3-2-14 Comparison of streakline plots according to 500K, 750K and 1000K(XL=2m, θ=60˚) 102
Fig.3-3-1 Schematic diagram of cyclone slagging combustor 109
Fig.3-3-2 Boundary condition of cyclone slagging combustor 117
Fig.3-3-3 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 20㎏/hr) 126
Fig.3-3-4 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 30㎏/hr) 127
Fig.3-3-5 Velocity vector plot, temperature plot and fuel fraction Plot of precombustor(Coal 35㎏/hr) 128
Fig.3-3-6 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 40㎏/hr) 129
Fig.3-3-7 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 20㎏/hr) 130
Fig.3-3-8 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 30㎏/hr) 131
Fig.3-3-9 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 35㎏/hr) 132
Fig.3-3-10 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 40㎏/hr) 133
Fig.3-3-11 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 20㎏/hr, X1=2cm) 134
Fig.3-3-12 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 30㎏/hr, X1=2cm) 135
Fig.3-3-13 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 38㎏/hr, x1=2cm) 136
Fig.3-3-14 Velocity vector plot, temperature plot and fuel fraction plot of precombustor(Coal 43㎏/hr, X1=2cm) 137
Fig.3-3-15 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 20㎏/hr, X1=2cm) 138
Fig.3-3-16 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 30㎏/hr, X1=2cm) 139
Fig.3-3-17 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 38㎏/hr, X1=2cm) 140
Fig.3-3-18 Velocity vector plot, temperature plot and fuel fraction plot of main combustor(Coal 43㎏/hr, X1=2cm) 141
Fig.3-3-19 Comparison of temperature profiles between this prediction and experimental data 142
Fig.3-3-20 Comparison of temperature profile for second air inlet 2cm between this prediction and experimental data 143
Fig.3-3-21 Comparison of tangential velocity profiles of precombustor 144
Fig.3-3-22 Comparison of tangential velocity profiles of main combustor 145
Fig.3-3-23 Comparison of velocity vector plots of precombustor for various inlet area(Coal 30㎏/hr) 146
Fig.3-3-24 Comparison of velocity vector plots of precombustor for various inlet area(Coal 40㎏/hr) 147
Fig.3-3-25 Comparison of velocity vector plots of precombustor for various inlet area(Coal 50㎏/hr) 148
Fig.3-3-26 Comparison of pressure contours for various inlet area(Coal 40㎏/hr) 149
Fig.3-3-27 Velocity vector plot, temperature plot and fuel fraction plot of precombustor with injection angle 80˚(Coal 30㎏/hr) 150
Fig.3-3-28 Velocity vector plot, temperature plot and fuel fraction plot of main combustor with injection angle 80˚(Coal 30㎏/hr) 151
Fig.3-3-29 Velocity vector plot, temperature plot and fuel fraction plot of main combustor with second air inlet 2cm 152