第三章理想气体的热力学能、

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峨陶
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2 u = f ( ) 3345 ( du) = ( δq) = c d V c V0 duc V0 d3 u u c V d 3a c V 0 V 0 V

3 huvu R g hf 3 5 dh) (δq) c d c 0 dhc 0 d3 h h c d 3a c 0 0 Ku 0 0 Ku 0 0 J/kgh 0 u 0 0 v 0 u 0 R g 0 0 J/kg 0

4 q c V ( δ ) V d q c ( δ ) d 4" u u δq dudv[ ( ) V d ( ) dv]dv v u u δq ( ) V d [ ( ) ]dv v dv0 u (δq) V ( ) V d u cv ( ) V 33 K 33 h δq dhvd[ ( ) h δq ( ) h d ( ) h d[ ( ) d0 v]d d]vd

5 h (δq) ( ) d h c ( ) 34 K 34 u du ( ) V d h dh ( ) d 33 u du c V0 ( ) V 35 d h dh c 0 ( ) 36 d K dh d c 0 (uv d d vr g du d c 0 (Rg c V0 R g d d

6 c 0 c V0 R g 37 c 0 m,0 /Mc V0 m,v0 /M m,0 m,v0 R37a R J/mol K γ 37 c γ c 0 V 0 R γ c V0 R g 38 γ γ c 0 R g 39 γ g c V c 0 a 0 a a a 3 3 c V0 a 0 a a a 3 3 a 0 a a a 3 37a 0 a 0 R g 3 a3a

7 c t, m 0 c, c, 0 t V m 0 t m 0 c, t m 0 / O N O O H O SO t c, 0 t V m 0 t

8 t t c, m 0 c t 0 0d t cv, m 0 t t cv, m 0 c V t 0 0d

9 c d c d c d d ) 0 cv t t 0 t 0 0 t c 0 0 t t c 0d c, m 0 c, m 0 3 t t 0d c V, m 0 c V, m 0 3a kw W & q m h h ) s ( h dh ( ) dc d h h c dc ( ) c 4.87 kj/(kg K) W& s W& s q m h h c ( ) 80 kw kg/s 70 kg/h 4.87 kj/(kg K) 40 K 7 37 kg 34

10 d0 q (h h ) q h h c d kj/(kg K) kg q h h c 0 ( ).004 kj/(kg K)(600300) K30. kj/kg { m, 0} J (mol K) {} K {} K v d {} K J/(mol K) q h h M m, 0 d 8.97 g/mol [8.5( ( ) ( ) ( ) ] J/(mol K) J/g309 kj/kg 3 3 c 7 m 0 3 q h h kj/(kg K) c c d c 0 37 m 0 37 m kj/(kg K) 7 c m 0 c 7 m kj/(kg K)37 K kj/(kg K)7 K kj/kg Kh kj/kg 600 Kh 607.0

11 kj/kg q h h kj/kg300.9 kj/kg kj/kg 0. % δq ds ( ) 3 ds δq ( ) rev rev 3a δq dudv δq dhvd

12 d u + dv ds dh vd ds du dh dv v d duc V0 d dhc 0 d vr g d dv d v d dv dsc V0 Rg 33 v d d dsc 0 Rg 34 dsc V0 d dv c0 v 35 v s s c V0 l Rg l 33a v s s c 0 l s s c V0 l Rg l c0 l v v 34a 35a

13 s 0 s 0 c 0 0 d 0 s 0 s s d c Rg l c 0 d Rg l c 0 d s s s s s R g l 36 s m 3 t MPa 0.08 MPa0

14 S S m(s s )m[ c 0 m V R g d Rg l ] R g 0.87 kj/(kg K) Pa 0.5 m m.35 kg 87.7 J/(kg K) ( ) K s s c 0 l Rg l c kj/(kg K) 93 K s s.004 kj/(kg K)l 43 K Pa 0.87 kj/(kg K) l Pa kj/(kg K) m(kg) S S ms s.35 kg kj/(kg K) kj/k3.3 J/K 0 0 s s s s R g l K kj/(kg K) 43 K s kj/(kg K) s s kj/(kg K) kj/(kg K) Pa 0.87 kj/(kg K) l Pa kj/(kg K)9.8 J/(kg K) m S S m(s s ).35 kg9.8 J/(kg K).34 J/K s

15 VR mm m m i m i i i R i i V i i= i i= V R V R 37

16 V i i R V i i V i i= R i= i R V V V V38 i i V i R V i i R i V V i 39 w i y i ϕ i w i m m i

17 y i i ϕ i V V i w w w y y y ϕ ϕ ϕ V ϕ i i i R i V R ϕ i y i 30 m w i i i M i m M M w i y i i 3 M m w i i V i ρ i m V ρ ρ w i i ϕ i 3 ρ M ρ m m ρ + m + L+ mi ρ V + ρv + L+ ρ Vi i V V V ρ ρ ϕ ρ ϕ ρ ϕ 33 m m m ρ m m m ( + + L+ ) V V + V + L+ V ρ ρ ρ

18 w w ρ ( + + L+ ) 34 ρ ρ ρ m m m M m m m ( + + L+ ) + + L+ M M M w w w M ( + + L+ ) 35 M M M m m M + m + L+ m M + M + L+ M My M y M y M 36 R g M R 3635 R g R ( ym + ym + L+ y M ) 37 w w w R g R ( + + L+ ) 38 R R R g g w g y y y R g ( + + L+ ) 39 M M M R g w R g w R g w R g 330 UU U U 33 mum u m u m u

19 uw u w u w u 33a HUV (U U U )(V V V ) HH H H 33 mhm h m h m h hw h w h w h 33a 35 du d c V0 w u w u w u d d c V0 w c V0 w c V0 w c V dh d c 0 w h w h w h d d c 0 w c 0 w c 0 w c '334 m, 0 m, 0 m, 0 m, 0 w w w M M M M 3w i y i ( M i M )

20 m,0 y,m0 y m,0 y m, m,v0 y V,m0 y m,v0 y m,v0 336 A0.3 kg0 B 0. kg00 U A U B U A U B U A U A m A U B U B m B A B c V 0Ad c V 0Bd m A c V0A ( A m B c V0B ( B m A c V0A ( A )m B c V0B ( B ) macv 0AA + mbcv 0BB m c + m c A V 0A B V 0B c V kj/(kg K) c V kj/(kg K) 0.3 kg kj/(kg K) 93 K + 0. kg kj/(kg K) 73 K 0.3 kg kj/(kg K) + 0. kg kj/(kg K) 37.4 K54.4

21 du/d) V dh/d) q/d) V q/d) kg mol800 K 000 K 0 MPa0 0 cm m 3.5 MPa 37 MPa3. 0. MPa7 0. MPa MPa30 0. MPa 0 mol300 K50 K mol0 300 K800 K c 37 m 5 0. kg0. MPa7 0.5 MPa

22 mol300k600 K0. MPa 0.5 MPa 0.6 MPa7 0.6 MPa kj/kg MPa7 0. MPa MPa7 50 kg 0.4 w 0.06 wo O w H O wn wo w N kg w g MPa3

23 wo w N 5 w w N O wh O w O 0.78 AB V A.5 m 3 A 6.86 bar A 80 V B m 3 B 9.8 bar B J ABAB A B V A V B A B A B AB A A B V B A V A B B + + V + V V + V A B A B A B A B

第一章绪论

第一章绪论 1-1 1-1 1-5 0.05 1-6 1 60mm 1.5W/(m K) 5-5 m C 1-7 1cm, 0 m 1.04W/(m K) C C 50 50 4.09 10 kj/kg C 1-9 =69 C f =0 w C =14mm d 80mm 8.5W 1-11 10mm 0 C 85 C ( ) 175 W m K 1mm 1-14 T0 0K T = w 50K ε = 0. 7

第三章 理想气体的热力学能、

第三章理想气体的热力学能、