7. . (7.1]. :1. ( );2. ( );3. ;4. . . , .7.1. . , (7.2), (7.3).
, (7.4|.7.2. (h1, W/(m2K))
(7.1.) : l, W/(m K), , l, kg/m3, , g, kg/m3, , l, Pa s, , r,
J/kg, g, m/s2, ds,m, t, C, . (tsr, C), (tkond, ) (tz, ) [7.5]
(7.2.) (7.1)
(7.3.)(7.3) :h,kg/(ms)
mkond, kg/s, L,m, . , (7.1)
(7.4) :q, W/m2, . ( 7.1.a) , .
7.1 (h,sr, W/(m2K)) (Nr) [7.6]
, ( 7.1.b) [7.7]
:-Dcc, m, ,-t, m, . (7.3) (Nc).
, kg/(ms) e , , , ( ) ( ) [7.7]:
:-, 1,0 0.8 ,
(7.9)-cpl, /(kg), , Prl, , Re, .
-wg, m/s, . (7.8):
. , , . . ( 7.2)
(7.12)[7.7]
, mm
:
7.2 Lp, mm, Du, mm, e e 6. . , , e , ( , ).7.3. (v,
W/(m2K)):
(7.1) (L, m). (7.14), [7.3] 20%, :
:
: v, kg/(ms)
(7.18) (7.15) 30. Re . (7.1):
(7.15) 30 , (7.15) 2000. :
(7.19) 2000 [7.5]. (7.20), 7.3
:Prl, , .
"/ :- ,. . 7.3 7.3 . , (7.20) , . . [7.9] (x, kg /kg )
:
() () , u, W/(m2K), ( ) , . . (7.21)
(7.20) (7.21). , , ( -) . [7.10]:
:du, m, . (wg, m/s) (wl, m/s) , .7.4. - ( ) . , . , (7.21).7.3.
( ), |7.1]. , . . , 25 % ( < 0,25), , .
g :... hp, J/kg, h",J/kg, . , :
g :-h', J/kg, . (tkond, C), :
: t2p, C, t2k,. . , (x> 0,8) c rx. , . .7.4. . -. , ( 7.4),
.
7.4 200 W/(m2K)[7.1]. , . .7.5. . . , . . . (, kg /kg ) 7.5.
(nk, W/(m2K)) . [7.11].
7.5 7.5 1 % 60 %. , 7.5.7.6. , . .
7.6 e , . , . 40 + 50 % , . . (mlsr) , (7.12):
: tul,C, tiz, . (mlul/mliz; tul/tiz), ( 7.6). , . 78. . , , , .
, , , .[8.1], [8.2]- 8.1 - , 6 - , - , , (. ) . , , , . , , ( ). ,
, . 8.1 [8.3]:1) ( ). , . . , . , . . , .2) ( ). . . ( 8.6). , .
0,3bar. , . . , .3) ( ). , .
8.2 ( 8.2). , . . , . .8.1. () . . , (8.4). , . ( 9m/s). , , . (
8.3):
8.3 1) ( ) . . .2) , ( ), .3) . . - . .4) . . (ki,W/(m2K ))
[8.41]:
: 'pk, (W/(m2K)), 'mk, (W/(m2K), . - XLM [8.5]:
: pk, (W/(m2K)), , (Rl)
, n i( 8.4).
-x, kg /kg , Rl,
mp, kg/s
. 5.4 du, m, -g', kg/m3, -g, kg/m3, g, Pas, l, Pas, e (mk,
(W/(m2K))
:mk, W/(m2K),
, ( 8.5). (mk, W/(m2K)) [8.6]
8.5. fmk
:-l,W/(mK) -cpl, J/(kgK), /, ,
