, , , . .
(, , ..).
, , , , . .
, , . , , ..
.
, . .
, .
, , .
X :
=.δ.
) ;
) , . + δ .- δX.
δ .
δ , .+δ , .-δ .
, n ( ) n 1,2,,n. :
()
4-5. , , , δ=σ. σ :
()
N .
, :
. 1 100 , 1 3 . , δ, δ , , .
|
|
.
=
, . , , ..., . , , , ... :
Z=α(x,y, ,w).
, , , ... δ, δ, , ,... z, ., , , δ, δ, , δz z.
,...,w δ...δw g=+...+g-(u+...+w), δz ≈ δ+... δg+ δu+...+ δw .
,..w δ... δw z ,...w:
. x δ z=, , z ||, : δz=||δ.
δ z=xn, z n :
N=+++... | (∆+∆+∆+...) | |
N=- | (∆+∆) | |
N= | (∆+∆) | (∆/+∆/) |
N=ABC | (∆+∆+∆) | (∆/+∆/+∆/) |
N=1/n | 1\n-1 | |
N=n | nn-1∆ | n∆\ |
N=/ | (∆+∆)/2 | (∆/+∆/) |
N=sin(A) | s()∆ | ctg()∆ |
=cos(A) | sin()∆ | tg()∆ |
7. :
W1 = 2020 3, t1 =16 ,
W2 =2558 3, t2 =20 c,
W3 =1612 3, t3 =13 ,
Q1= W1/ t1 =126,2 3/,
Q2= W2/ t2 =127,9 3/,
Q3= W3/ t3 =124 3/.
: 3, , 3/, /, /2, .
, :
( 90º) :
|
|
d , 20 .
( ) h1 =72 , ( ) h2 =68 , ∆h = 72-68=4 .
( 90º):
:
8. , d1 =20 , d2 =50 .
∆h1 =1,7 , ∆h2 =1,5 , ∆h3 =1,3 .
∆h:
( V1 =40 c/):
6. (Re.) ( 2 3 0,2 ).
Re..
, , .
5 :
W1 =865 3, Q1 =57,7 3/, t1 =15 ,
W2 =1174 3, Q2 =58,7 3/, t2 =20 ,
W3 =1417 3, Q3 =56,7 3/, t3 =25 ,
W4 =1298 3, Q4 =59 3/, t4 =22 ,
W5 =1392 3, Q5 =58 3/, t5 =24 .
():
, .
Q ():
Q =580,4 3/.
0,4/58100% ≈ 1%.
0,01.
:
Re , , ν ( ).