㳿. , , , , , .
./,
v () , /;
l , .
,
./, (6.7)
k .
Q Q.
. (6.8)
.
k = k1 × k2 × k3 ×... × ki,
k1 , ( );
k2 , (, );
k3 , .
l/d << 1, l/d >> 1 k = 0,7...0,9. l/d ≈ 1 k = = 0,4 0,5.
k = 0,6...0,7.
:
k = 0,6;
k = 0,4;
(, ) k = 0,2.
- , , , Q Q
Q = kn · Q, (6.9)
k = 1,1...1,3 , .
, , , 50 100 50 .. 100 D ≤ 200 . ( D = 200...500 ) 50 .
, . α = 1...3. a (α = 10...12 ).