, υ
υ n = Const, (4.20)
n.
, (4.20) . n ∞ +∞.
:
2/ 1 = ( 2/ P 1)( n -1)/ n; (4.21)
υ 1/ υ2 = ( 2/ P 1)1/ n; (4.22)
2/ 1 = (υ 1/ υ2) n -1. (4.23)
:
ℓ= R /(n 1) ( 1 2). (4.24)
:
n = C υ (n k)/(n 1). (4.25)
( ) :
q = n ( 2 1). (4.26)
, .
n n
+∞ C υ
0
頠 1 ∞
頠 k 0
3
1 n = 2 P 1 = 0,1 , t 1 = 20 2 = 7 . R = 287 / = 1,0 / .
:
2 = 1 ( 2/ P 1)( n -1)/ n = 293,15 (7/0,1)(2-1)/2 = 2452,7 ;
ℓ= R /(n 1) ( 1 2) = 619,8 /;
C υ = R = 713 / ;
q = C υ (n k)/(n 1)(T 2 1) = 923,855 /.
: ℓ = 619,8 /, q = 923,855 /.
4.6. . υ
(. 4.1)
, . , .
P
I III
0′ 1′ 2′ 2 3′
0 1 2 1 3
x = 1
x = 0
A II B
x 1 x 2 x 3 x 4
υ
. 4.1
:
0-1 0′-1′ () 1 2, ; 1-2 1′-2′ - ; 1 1′ ; 2 2′ ; ( = 0, = 1); 2-3 2′-3′ ; ( t = 374,15 , = 225,65 , υ = 0,0031 3/).
|
|
, , .
I , II , III .
, .. ′, t ′, h ′, υ′, S ′ .., , . . ′′, t ′′, h ′′, υ′′, S ′′ ..
, 1 t 0 t ′, :
q 1 = C ′ (t ′ t 0). (4.27)
, 1 , :
q 2 = r = h ′′ h ′. (4.28)
, t ′′ t 3, :
q 3 = C ′′ (t 3 t ′′). (4.29)
(4.27)(4.29) :
C ′ , t 0 t ′, / ; r , /; h ′′ h ′ , , /;
′′ t ′′ t 3, / .
4
, 1 t 1 = 20 t 2 = 110 = 0,1 .
4.
, 1 :
q = q 1 + q 2 + q 3 = C ′ (t t 1) + r t + ′′ (t 2 t ).
t .
C ′ = ( ′(t ) + ′(t 1))/2 = (4,22 + 4,18)/2 = 4,2 / ,
′ = ( ′(t 2) + ′(t ))/2 = (1,9 + 1,87)/2 = 1,885 / ,
r = 2260 /.
q = 4,2(10020) + 2260 + 1,885(110 100) = 336 + 2260 + 18,85= = 2614,85 /.
4.7.
(. . , )
q = (t c1 t c2)/ R λ, (4.30)
t c1 t c2 , ; R λ = δ/λ , 2 / ; δ , ; λ , / .
:
|
|
q = (t c1 t c (n +1))/ R λ i , (4.31)
t c1 t c ( n +1) 1 n +1, ; R λ i = R λ1+ R λ2+ R λ3++ R λ n n .
(4.30) (4.31)
I = U / R, (4.32)
I ; U ; R .
5
(. 4.2), δ = 3 , δ = 12 δ = 6 , t c1 = 40 , t c2 = + 20 . λ = 0,78 / , λ = 0,25 / , λ = 0,1 / . .
t c2
t c1
q
δ δ δ
. 4.2
q = (t c2 t c1)/(δ/ λ + δ/ λ + δ/ λ) = (20 + 40)/(0,03/0,78 + 0,12/0,25 + + 0,06/0,1) = 60/(0,03846 + 0,48 + 0,6) = 60/1,11846 = 53,645 /2.
t ′2 :
q =(λ/ δ)(t c2 t ′2).
t ′2 = t c2 (q δ)/ λ = 20 (53,645*0,06)/0,1 = 20 32,187 = 12,2 C.
q = (λ/ δ)(t ′2 t ′1)
t ′1 = t ′2 (q δ)/ λ = 12,2 (53,645*0,12)/0,25 =
= 12,2 25,7 = 37,9 C.
(. 4.3).
t C
20
10
0
3 6 9 12 15 18 21 δ,
10 12,2
20
30
37,9
40
. 4.3
. , . . .
3 . , , , - , .
(), 2.105-68 . , 9867-61.
. .