RESULTS AND DISCUSSION
4.6 Comparison of Vortex Flows with and without Showerhead Installation
4.6 Comparison of Vortex Flows with and without Showerhead Installation
To further reveal the effects of the showerhead installation on the resulting vortex flow, we compare the vortex flow in the same chamber with and without showerhead installation. By installing the showerhead, the large-diameter gas jet at the injection nozzle is broken into a great number of the tiny jets (Fig. 4.43). The tiny jets move at a much high speed because Vj / Vn = Dn2 / (Ndj2) = 47.4 but at a much lower Reynolds number Rej / Ren = Dn / (Ndj) = 0.311. Figures 4.44-46 shows the flow photos taken from the chamber with and without showerhead installed for the limiting cases of ∆T = 0℃ at the same H and Qj. Note that the inertia-driven vortex rolls are large and strong at high Qj when no showerhead is installed (Figs. 4.44(a), 4.45(a) ＆ 4.46(a)) for Qj ≥ 2.0 slpm. With the showerhead installation the inertia-driven rolls are much smaller and weaker (Figs. 4.44(b), 4.45(b)＆4.46(b)) and there rolls appear in the outer zone of the chamber. We further make this comparison for ∆T ≥ 5.0℃ in Figs. 4.47-4.52 for H = 20.0 to 40.0 mm. The results clearly show that the showerhead installation can effectively suppress the inertia-driven rolls. But the buoyancy-driven roll may become larger and stronger. Besides from Table 4.3, the onset of the inertia-driven rolls without the showerhead installation for the disk unheated (Ra=0) indicate that the primary and secondary rolls appear earlier than that with the showerhead installation.
37
Table. 4.1 Critical condition for the onset of the primary and secondary inertia-driven vortex rolls for H = 20-40 mm with disk unheated (Ra=0)
Separation Distance
( H, mm)
Flowrate
(Qj,SLPM) Ren Rej
Primary inertia-driven
roll
20 1.6 28 8.7 30 1.7 30 9.3 40 2.0 35 11 Secondary
inertia-driven roll
20 3.7 66 20 30 1.8 32 10 40 2.2 39 12
.
38
Table. 4.2 Critical condition for the onset of the primary inertia-driven vortex roll for H = 20-40 mm with heated disk
Separation Distance ( H, mm)
ΔT (°C )
Flowrate
(Qj,SLPM) Rej Ren Ra Gr/Rej2 Gr/Ren2
20.0
5 1.8 10 32 3,758 54.38 5.26
10 2.5 14 44 7,516 56.38 5.45
15 3.0 17 53 11,274 58.73 5.68
20 3.2 18 57 15,032 68.83 6.65
25 3.4 19 60 18,790 76.21 7.37
30.0
1 2.1 12 37 2,536 26.97 2.61
2 2.2 12 39 5,073 49.14 4.75
3 2.3 13 41 7.610 67.45 6.52
4 2.3 13 41 10,146 89.93 8.69
5 2.4 13 43 12,683 103.24 9.99
7 2.5 14 44 17,757 133.20 12.88
10 2.6 14 46 25,367 175.93 17.02
15 2.9 16 51 38,051 212.12 20.52
20 3.1 17 55 50,734 247.51 23.93
25 3.3 18 59 63,418 273.03 26.41
39
Table. 4.2 Continued Separation
Distance ( H, mm)
ΔT (°C )
Flowrate
(Qj,SLPM) Rej Ren Ra Gr/Rej2 Gr/Ren2
40.0
1 2.3 13 41 6,013 53.29 5.15
2 2.4 13 43 12,026 97.89 9.46
3 2.5 14 44 18,039 135.32 13.09
4 2.6 14 46 24,052 166.81 16.13
5 2.8 15 50 30,065 179.79 17.38
10 3.1 17 55 60,130 293.35 28.37
15 3.3 18 59 90,195 388.32 37.56
20 3.5 19 62 120,260 460.26 44.52
25 3.7 20 66 150,325 514.81 49.79
40
Table. 4.3 Critical condition for the onset of the primary and secondary inertia-driven vortex roll without showerhead for H = 20-40 mm with disk unheated (Ra=0)
Separation Distance
( H, mm)
Flowrate
(Qj,SLPM) Ren
Primary inertia-driven
roll
20 1.5 27 30 1.6 28 40 1.8 32 Secondary
inertia-driven roll
20 2.0 35 30 1.8 32 40 2.2 39
41
θ=0° θ=180°
θ=180°
θ=0°
Showerhead Buoyancy-driven roll
Sidewall
Insulation Heating plate
(a) Sidewall
Insulation Heating plate
(b)
Fig. 4.1 Natural convection flow pattern in the chamber with H = 20.0mm for Rej = 0 (Qj = 0 slpm) and Ra = 18,790 (ΔT = 25℃) for (a) side view flow photo taken at the cross plane θ=0° & 180° and (b) the corresponding schematically sketched cross plane vortex flow.
42
θ=0° θ=180°
θ=0° θ=180°
Showerhead Gas - Flow
Corner roll Primary inertia-driven roll
Sidewall
Heating plate Insulation
Secondary inertia-driven roll (a)
Gas - Flow
Showerhead Sidewall
Heating plate Insulation
(b)
Fig. 4.2 Inertia driven flow pattern in the chamber with H = 30.0mm for Ren = 89, Rej = 28 (Qj = 5.0 slpm) and Ra = 0 (ΔT = 0℃) for (a) side view flow photo taken at the cross plane θ=0° & 180° and (b) the corresponding schematically sketched cross plane vortex flow.
43
Side view flow photos taken at the c
θ=0° θ=180°
θ=0° θ=180°
θ=0° θ=180°
Gas - Flow
Showerhead
(a) H = 20.0 mm
(b) H = 30.0 mm
(c) H = 40.0 mm
Fig. 4.3 ross plane θ=0° & 180° at Rej = 14 (Qj = 2.0 slpm, Ren = 35) and ΔT=0℃ (Ra=0) for (a) H = 20.0 mm, (b) H = 30.0 mm and (b) H = 40.0 mm.
Primary inertia-driven roll Corner roll
Sidewall
Heating plate Insulation
Corner roll Primary inertia-driven roll
Sidewall
Insulation Heating plate
Primary inertia-driven roll Corner roll
Sidewall
Insulation Heating plate
44
Side view flow photos taken at the c
θ=0° θ=180°
θ=0° θ=180°
θ=0° θ=180°
(a) H = 20.0 mm
(b) H = 30.0 mm
(c) H = 40.0 mm
Fig. 4.4 ross plane θ=0° & 180° at Rej = 22 (Qj = 4.0 slpm, Ren = 71) and ΔT = 0℃ (Ra = 0) for (a) H = 20.0 mm, (b) H = 30.0 mm and (b) H = 40.0 mm.
Heating plate Insulation
Gas - Flow
Showerhead Corner roll Primary inertia-driven roll
Secondary inertia-driven roll Sidewall
Insulation Heating plate
Primary inertia-driven roll
Secondary inertia-driven roll
Corner roll Sidewall
Insulation Heating plate
Primary inertia-driven roll
Secondary inertia-driven roll
Corner roll Sidewall
45
θ=0° θ=180°
θ=0° θ=180°
(a) H = 20.0 mm
(b) H = 30.0 mm
(c) H = 40.0 mm
Fig. 4.5 Side view flow photos taken at the cross plane θ = 0° & 180° at Rej = 11 (Qj = 2.0 slpm, Ren= 35), and ΔT=10℃ for (a) H = 20.0 mm (Ra = 7,516), (b) H = 30.0 mm (Ra = 25,367), and (c) H = 40.0 mm (Ra = 60,130).
Heating plate Insulation
Gas - Flow
Showerhead
Buoyancy-driven roll Primary inertia-driven roll
Sidewall
Buoyancy-driven roll Sidewall
Heating plate Insulation
Buoyancy-driven roll Sidewall
Heating plate θ=180°
Insulation
θ=0°
46
θ=0° θ=180°
θ=0° θ=180°
(a) H = 20.0 mm
(b) H = 30.0 mm
(c) H = 40.0 mm
Fig. 4.6 Side view flow photos taken at the cross plane θ = 0° & 180° at Rej = 28 (Qj = 5.0 slpm, Ren = 89), and ΔT = 10℃ for (a) H = 20.0 mm (Ra = 7,516), (b) H = 30.0 mm (Ra = 25,367), and (c) H = 40.0 mm (Ra = 60,130).
Heating plate Insulation
Gas - Flow
Showerhead
Primary inertia-driven roll
Buoyancy-driven roll Sidewall
Buoyancy-driven roll Primary inertia-driven roll Sidewall
Heating plate Insulation
Primary inertia-driven roll Buoyancy-driven roll
Sidewall
Insulation θ=180°
θ=0° Heating plate
Primary inertia-driven roll
Fig. 4.7 Schematic illustration of the streamlines through the showerhead and impinging onto the heated disk.
47
θ=180°
θ=0° Heating plate Insulation
Sidewall
Gas - Flow
Showerhead
Secondary inertia-driven roll
Primary inertia-driven roll Corner roll
(a) H = 20.0 mm
Secondary inertia-driven roll Primary inertia-driven roll
48
θ=0° θ=180°
(b) H = 30.0 mm
(c) H = 40.0 mm
Fig. 4.8 Side view flow photos taken at the cross plane θ = 0° & 180° at Rej = 28 (Qj = 5.0 slpm, Ren = 89), and ΔT = 0℃ for (a) H = 20.0 mm, (b) H = 30.0 mm, and (c) H = 40.0 mm.
Sidewall
Heating plate Insulation
Secondary inertia-driven roll Primary inertia-driven roll Sidewall
Heating plate
Insulation θ=180°
θ=0°
Gas - Flow
Insulation Heating plate
Sidewall
Primary inertia-driven roll
Buoyancy-driven roll Primary inertia-driven roll Buoyancy-driven roll Primary inertia-driven roll
Buoyancy-driven roll
Buoyancy-driven roll
Gas - Flow
Showerhead
50
θ=0 θ=180
Fig. 4.10 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 3,758 (ΔT = 5℃) and H = 20.0 mm for Ren = (a) 9, (b)
Sidewall Buoyancy-driven roll (a) Primary inertia-driven roll
(h)
Buoyancy-driven roll Primary inertia-driven roll (i)
Buoyancy-driven roll
Primary inertia-driven roll
51
Fig. 4.10 Continued.
Ren=35 (11) (Qj=2.0 slpm)
(j) Steady
Buoyancy-driven roll Primary inertia-driven roll
Ren=44 (14)
(k) (Qj=2.5 slpm)
Steady Buoyancy-driven roll Primary inertia-driven roll
Ren=53 (17)
(l) (Qj=3.0 slpm)
Steady Buoyancy-driven roll Primary inertia-driven roll
Ren=71 (22)
(m) (Qj=4.0 slpm)
Steady Buoyancy-driven roll Primary inertia-driven roll
Ren=89 (28)
(n) (Qj=5.0 slpm)
Steady Buoyancy-driven roll
Gas - Flow
Showerhead
52
θ=0 θ=180
Fig. 4.11 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 7,516 (ΔT = 10℃) and H = 20.0 mm for Ren = (a) 18, (b) 23, (c) 25, (d) 28, (e) 35, (f) 41, (g) 44, (h) 53, (i) 71 and (j) 89.
( ) : The number in the ( ) is the jet Reynolds number.
Ren=18 (6) Corner roll
Sidewall Buoyancy-driven roll
(a) (Qj=1.0 slpm)
Steady
Insulation Heating plate
Ren=23 (7)
Buoyancy-driven rolls Unsteady
Ren=89 (28)
Buoyancy-driven roll Primary inertia-driven roll (g)
Buoyancy-driven roll Primary inertia-driven roll (h)
Buoyancy-driven roll Primary inertia-driven roll (i)
Buoyancy-driven roll Primary inertia-driven roll (j)
Buoyancy-driven roll
Gas - Flow
Showerhead
53
θ=0 θ=180
Fig. 4.12 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 11,274 (ΔT = 15℃) and H = 20.0 mm for Ren = (a) 18,
Insulation Heating plate
Ren=27 (8) Primary inertia-driven roll
Primary inertia-driven roll
Ren=57 (18)
Primary inertia-driven roll
54
Fig. 4.12 Continued.
Ren=59 (18) (Qj=3.3 slpm)
(j) Steady
Buoyancy-driven roll Primary inertia-driven roll
Ren=62 (19)
(k) (Qj=3.5 slpm)
Steady Buoyancy-driven roll Primary inertia-driven roll
Ren=71 (22)
(l) (Qj=4.0 slpm)
Steady Buoyancy-driven roll Primary inertia-driven roll
Ren=89 (28)
(m) (Qj=5.0 slpm)
Steady Buoyancy-driven roll
55
Fig. 4.13 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 15,032 (ΔT = 20℃) and H = 20.0 mm for Ren = (a) 18, Primary inertia-driven roll
Ren=57 (18)
Insulation Heating plate
(b)
Primary inertia-driven roll
56
Fig. 4.13 Continued.
Ren=89 (28) (Qj=5.0 slpm) Steady
Ren=71 (22) (Qj=4.0 slpm) Steady
Ren=62 (19) (Qj=3.5 slpm) Steady
(j)
Buoyancy-driven roll Primary inertia-driven roll (k)
Buoyancy-driven roll Primary inertia-driven roll (l)
Buoyancy-driven roll
57
θ=0 θ=180
Gas - Flow
Showerhead Buoyancy-driven roll
Fig. 4.14 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 18,790 (ΔT = 25℃) and H = 20.0 mm for Ren = (a) 18,
Insulation Heating plate
Ren=27 (8)
Buoyancy-driven roll Primary inertia-driven roll (i)
Buoyancy-driven roll
Primary inertia-driven roll
58
Fig. 4.14 Continued.
Ren=89 (28) (Qj=5.0 slpm) Steady
Ren=80 (25) (Qj=4.5 slpm) Steady
Ren=71 (22) (Qj=4.0 slpm) Steady
Ren=64 (20) (Qj=3.6 slpm) Steady
Ren=62 (19) (Qj=3.5 slpm) Steady
(j)
(k)
(l)
Buoyancy-driven roll Primary inertia-driven roll
Buoyancy-driven roll Primary inertia-driven roll
Buoyancy-driven roll Primary inertia-driven roll (m)
Buoyancy-driven roll Primary inertia-driven roll (n)
Buoyancy-driven roll
59
θ=0° θ=180°
Fig. 4.15 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 2,536 (ΔT = 1℃) and H = 30.0 mm for Ren = (a) 27, (b)
Showerhead Corner roll Buoyancy-driven roll
Buoyancy-driven roll Inertia-driven roll
Ren=44 (14) (Qj=2.5 slpm) Steady
(f)
Buoyancy-driven roll Inertia-driven roll
Ren=53 (17) (Qj=3.0 slpm) Steady
(g)
Buoyancy-driven roll
Corner roll Inertia-driven roll
60
Ren=71 (22) (Qj=4.0 slpm) Steady
(h)
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm) Steady
(i)
Buoyancy-driven roll Fig. 4.15 Continued.
61
θ=0° θ=180°
Fig. 4.16 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 5073 (ΔT = 2℃) and H = 30.0 mm for Ren = (a) 18, (b)
Corner roll Inertia-driven roll
62
Ren=71 (22) (Qj=4.0 slpm) Steady
(h)
Buoyancy-driven roll
Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm) Steady
(i)
Buoyancy-driven roll
Fig. 4.16 Continued.
63
θ=0° θ=180°
Fig. 4.17 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 7,610 (ΔT = 3℃) and H = 30.0 mm for Rej = (a) 35, (b)
Showerhead Corner roll Buoyancy-driven roll
Buoyancy-driven roll Inertia-driven roll
Ren=44 (14) (Qj=2.5 slpm) Steady
(f)
Buoyancy-driven roll Inertia-driven roll
Ren=53 (17) (Qj=3.0 slpm) Steady
(g)
Buoyancy-driven roll
Corner roll Inertia-driven roll
64
Ren=71 (22) (Qj=4.0 slpm) Steady
(h)
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm) Steady
(i)
Buoyancy-driven roll Fig. 4.17 Continued.
65
θ=0° θ=180°
Fig. 4.18 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 10,146 (ΔT = 4℃) and H = 30.0 mm for Ren = (a) 18, (b)
Corner roll Inertia-driven roll
66
Ren=50 (15) (Qj=2.8 slpm) Steady
(h)
Fig. 4.18 Continued.
Buoyancy-driven roll Inertia-driven roll
Ren=53 (17) (Qj=3.0 slpm) Steady
(i)
Inertia-driven roll
Ren=71 (22) (Qj=4.0 slpm) Steady
(j)
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm) Steady
(k)
67
θ=0° θ=180°
Fig. 4.19 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 12,683 (ΔT = 5℃) and H = 30.0 mm for Ren = (a) 18, (b)
Showerhead Corner roll Buoyancy-driven roll
Buoyancy-driven roll Inertia-driven roll
Buoyancy-driven roll Inertia-driven roll
(g)
Corner roll Inertia-driven roll
68
Fig. 4.19 Continued.
Ren=71 (22) (Qj=4.0 slpm) Steady
Ren=89 (28) (Qj=5.0 slpm) Steady
(h)
(i)
Buoyancy-driven roll Inertia-driven roll
69
θ=0° θ=180°
Fig. 4.20 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 17,757 (ΔT = 7℃) and H = 30.0 mm for Ren = (a) 18, (b)
Inertia-driven roll
70
Fig. 4.20 Continued.
Ren=53 (17) (Qj=3.0 slpm) Steady
Ren=62 (19) (h)
Buoyancy-driven roll Inertia-driven roll
(i) (Qj=3.5 slpm)
Steady Inertia-driven roll
Ren=71 (22)
(j) (Qj=4.0 slpm)
Steady
Buoyancy-driven roll Inertia-driven roll
Ren=80 (25)
(k) (Qj=4.5 slpm)
Steady
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm) Steady
(l)
Gas - Flow
71
θ=0° θ=180°
Fig. 4.21 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 25,367 (ΔT = 10℃) and H = 30.0 mm for Ren = (a) 18, Buoyancy - driven roll
Ren=71 (22)
(f) (Qj=4.0 slpm)
Unsteady Inertia - driven roll
Ren=89 (28)
(g) (Qj=5.0 slpm)
Steady Buoyancy-driven roll
Gas - Flow
72
θ=0° θ=180°
Showerhead
Fig. 4.22 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 38051 (ΔT = 15℃) and H = 30.0 mm for Ren = (a) 18, (b)
Inertia-driven roll Buoyancy-driven roll
73
Fig. 4.22 Continued.
Ren=89 (28)
(h) (Qj=5.0 slpm)
Steady
Gas - Flow
74
θ=0° θ=180°
Fig. 4.23 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 50,734 (ΔT = 20℃) and H = 30.0 mm for Ren = (a) 18, Inertia - driven roll
Ren=73 (23) (Qj=4.1 slpm)
(f) Unsteady
Inertia-driven roll Buoyancy-driven roll
Ren=80 (25) (Qj=4.5 slpm)
(g) Unsteady
Inertia-driven roll
75
Buoyancy-driven roll
Ren=98 (28)
(h) (Qj=5.5 slpm)
Unsteady
Fig. 4.23 Continued.
Gas - Flow
76
θ=0° θ=180°
Fig. 4.24 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 63,418 (ΔT = 25℃) and H = 30.0 mm for Ren = (a) 18, Inertia-driven roll Buoyancy-driven roll
Ren=78 (24)
(g) (Qj=4.4 slpm)
Unsteady
Inertia-driven roll
77
Buoyancy-driven roll
Ren=89 (28)
(h) (Qj=5.0 slpm)
Unsteady
Fig. 4.24 Continued.
Gas - Flow
78
Showerhead
Buoyancy-driven roll Corner roll
Sidewall
Fig. 4.25 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 6,013 (ΔT = 1℃) and H = 40.0 mm for Ren = (a) 18, (b)
θ=0° Insulation Heating plate
Ren=30 (9)
Inertia-driven roll Corner roll
79
Continued.
Fig. 4.25
Ren=46 (14)
(g) (Qj=2.6 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=50 (15)
(h) (Qj=2.8 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=53 (17) (Qj=3.0 slpm)
(i) Steady
Inertia-driven roll Buoyancy-driven roll
Ren=71 (22) (Qj=4.0 slpm)
(j) Steady
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28)
(k) (Qj=5.0 slpm)
Steady
Gas - Flow
80
Showerhead
Buoyancy-driven roll Corner roll
Sidewall
Fig. 4.26 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 12,026 (ΔT = 2℃) and H = 40.0 mm for Ren = (a) 18, (b)
θ=0° Insulation Heating plate
Ren=35 (11)
Inertia-driven roll Buoyancy-driven roll
Ren=48 (15)
(f) (Qj=2.7 slpm)
Steady Buoyancy-driven roll
Corner roll Inertia-driven roll
81
Continued.
Fig. 4.26
Ren=53 (17)
(g) (Qj=3.0 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=71 (22)
(h) (Qj=4.0 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28_
(Qj=5.0 slpm)
(i) Steady
Gas - Flow
82
Showerhead
Buoyancy-driven roll Corner roll
Sidewall
θ=0° Insulation Heating plate
Ren=35 (11)
Fig. 4.27 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 18,039 (ΔT = 3℃) and H = 40.0 mm for Ren = (a) 18, (b)
Inertia-driven roll Buoyancy-driven roll
Ren=48 (15)
(f) (Qj=2.7 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
83
Continued.
Fig. 4.27
Ren=50 (15)
(g) (Qj=2.8 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=53 (17)
(h) (Qj=3.0 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=71 (22)
(i) (Qj=4.0 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28) (Qj=5.0 slpm)
(j) Steady
Gas - Flow
84
Showerhead Buoyancy-driven roll
Sidewall
Fig. 4.28 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 24,052 (ΔT = 4℃) and H = 40.0 mm for Ren = (a) 18, (b) 35, (c) 43, (d) 44, (e) 46, (f) 48, (g) 51, (h) 53, (i) 71 and (j) 89.
( ) : The number in the ( ) is the jet Reynolds number.
Ren=18 (6) (Qj=1.0 slpm)
(a) Steady
θ=180°
θ=0° Insulation Heating plate
Ren=35 (11)
(b) (Qj=2.0 slpm)
Steady Buoyancy-driven roll
Ren=43 (13) (Qj=2.4 slpm)
(c) Steady
Ren=44 (14) (Qj=2.5 slpm)
(d) Steady
Buoyancy-driven roll
Ren=46 (14)
(e) (Qj=2.6 slpm)
Steady Buoyancy-driven roll
Ren=48 (15)
(f) (Qj=2.7 slpm)
Unsteady
Inertia-driven roll
85
Continued.
Fig. 4.28
Ren=51 (16)
(g) (Qj=2.9 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=53 (17)
(h) (Qj=3.0 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=71 (22)
(i) (Qj=4.0 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28) (Qj=5.0 slpm)
(j) Steady
Gas - Flow
Fig. 4.29 Side view flow photos taken at the cross planeθ = 0° & 180° for various jet Reynolds numbers at Ra = 30,065 (ΔT = 5℃) and H = 40.0 mm for Ren = (a) 18, (b)
θ=0° Insulation Heating plate
Ren=35 (11)
Buoyancy-driven roll Inertia-driven roll
87
Continued.
Fig. 4.29
Ren=57 (18)
(g) (Qj=3.2 slpm)
Steady Buoyancy-driven roll
Inertia-driven roll
Ren=59 (18)
(h) (Qj=3.3 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=71 (22) (Qj=4.0 slpm)
(i) Steady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28) (Qj=5.0 slpm)
(j) Steady
Gas - Flow
Fig. 4.30 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 60,130 (ΔT = 10℃) and H = 40.0 mm for Rej = (a) 18, (b)
θ=0° Insulation Heating plate
Ren=27 (8)
89
Continued.
Ren=57 (18) (Qj=3.2 slpm)
(g) Unsteady
Ren=62 (19) (Qj=3.5 slpm)
(h) Unsteady
Inertia-driven roll Buoyancy-driven roll
Fig. 4.30
Ren=64 (20)
(i) (Qj=3.6 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=71 (22) (Qj=4.0 slpm)
(j) Steady
Inertia-driven roll Buoyancy-driven roll
Ren=80 (25) (Qj=4.5 slpm)
(k) Steady
Buoyancy-driven roll Inertia-driven roll
Ren=89 (28) (Qj=5.0 slpm)
(l) Steady
Gas - Flow
Fig. 4.31 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 90,195 (ΔT = 15℃) and H = 40.0 mm for Ren = (a) 18,
θ=0° Insulation Heating plate
Ren=35 (11)
91
Continued.
Ren=62 (19) (Qj=3.5 slpm)
(g) Unsteady
Buoyancy-driven roll Inertia-driven roll
Fig. 4.31
Ren=71 (22) (Qj=4.0 slpm)
(h) Steady
Inertia-driven roll Buoyancy-driven roll
Ren=80 (25)
(i) (Qj=4.5 slpm)
Steady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28)
(j) (Qj=5.0 slpm)
Steady
Gas - Flow
Showerhead Sidewall Buoyancy-driven roll
92
Fig. 4.32 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 120,260 (ΔT = 20℃) and H = 40.0 mm for Ren = (a) 18,
θ=0° Insulation Heating plate
Ren=35 (11)
Inertia-driven roll Buoyancy-driven roll
93
Continued.
Fig. 4.32
Ren=71 (22) (Qj=4.0 slpm)
(g) Unsteady
Buoyancy-driven roll Inertia-driven roll
Ren=80 (25)
(h) (Qj=4.5 slpm)
Unsteady
Inertia-driven roll Buoyancy-driven roll
Ren=87 (27) (Qj=4.9 slpm)
(i) Unsteady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28)
(j) (Qj=5.0 slpm)
Unsteady
Gas - Flow
Showerhead Buoyancy-driven roll
Sidewall
94
Fig. 4.33 Side view flow photos taken at the cross plane θ = 0° & 180° for various jet Reynolds numbers at Ra = 150,325 (ΔT = 25℃) and H = 40.0 mm for Ren = (a) 18, (b) 35, (c) 53, (d)59, (e) 60, (f) 62, (g) 71, (h) 80, (i) 89, (j) 98, and (k) 106.
( ) : The number in the ( ) is the jet Reynolds number.
Ren=18 (6) (Qj=1.0 slpm) Steady
(a)
θ=180°
θ=0° Insulation Heating plate
Ren=35 (11)
(b) (Qj=2.0 slpm)
Steady Buoyancy-driven roll
Ren=53 (17) (Qj=3.0 slpm)
(c) Steady
Buoyancy-driven roll
Ren=59 (18) (Qj=3.3 slpm)
(d) Steady
Ren=60 (19)
(e) (Qj=3.4 slpm)
Unsteady
Ren=62 (19)
(f) (Qj=3.5 slpm)
Unsteady
95
Continued.
Ren=71 (22)
(g) (Qj=4.0 slpm)
Unsteady Buoyancy-driven roll
Fig. 4.33
Ren=80 (25)
(h) (Qj=4.5 slpm)
Unsteady
Inertia-driven roll Buoyancy-driven roll
Ren=89 (28)
(i) (Qj=5.0 slpm)
Unsteady Buoyancy-driven roll
Inertia-driven roll
Ren=98 (30) (Qj=5.5 slpm)
(j) Unsteady
Buoyancy-driven roll Inertia-driven roll
Ren=106 (33)
(k) (Qj=6.0 slpm)
Unsteady