3 :
- ;
- ;
- .
() . , , . , .
, . , . . ( ) . , .
. ( ), , .
.
: qn =8000 / ≈ 2,22 /; h=20, n=2500; 0=200; λn = 10-3 /∙∙0; 1,1 /0; r = 0,7; ( ) m= 0,2; = 0,85 / 0; ρc=2500 /3; 100 , 4,18 / 0; r= 1705 /0, i = 1087 /.
:
0 = 2,22(1705∙0,7+1087-4,18∙20) ≈ 4877,1 /, (7.1)
: αn = λn/ (cn∙ρn) = 0,002/(1,1∙2000) = 0,9∙10-6 2/.
τ ( )
τ = = ∙ ≈ 0,281, (7.2)
:
A(t) = =. ≈35022, (7.3)
: n1 = m∙cr∙ρr+(1-m)∙c∙ρ∙(n- 0) = 0,2∙1705∙20+0,8∙0,85∙2500∙(250-20) = 397820 /3.
:
η = = ≈ 0,661, (7.4)
7.1
7.1 (t) (ήT)