5对流换热计算.pdf

文档介绍：ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
జǔజǔ ऋސ၏ऋސ၏
?5-1 ౧()˷ऋȏ ऋސ၏
?5-2 ऋȏ޶ȏ ऋސ၏
?5-3  ऋސ၏
?5-4 ॒ȏຨސ၏
?5-5 ࣋ސ၏
2005-8-2 1
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
??55--11 ౧౧(())˷ऋȏ ऋސ၏
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2005-8-2 2
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
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2005-8-2 3
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
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2005-8-2 4
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
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2005-8-2 5
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
u d
Re = m =< 2200   Ӏऋ
ν
Re∈ 2200104   
Re >104  
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2005-8-2 6
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
L L
ऋ34ࢍӀऋ ≈ ;
ऋ: ≈ 50
d d
LTw Lqw
34ࢍFš =Ӏऋ t ≈ Pr; t ≈ Re Pr
d d
L

ऋ: ≈ 50
d
2005-8-2 7
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
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t t ' 4q x ( c u d ) t
f = f + w ρ p m tw
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ρ tfš™§֧
t f = c p utdA ρc p udA
∫Ac ∫Ac
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2005-8-2 8
ΚƑܾ
ҔᏄҚ
HUST Lab of Thermal Science & Engineering
t
׷౧›™šT«s] $ऋ tw = C
ȏ™šžऋxy³8
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