3.总风阻等于各分支风阻之和,即: h+..+ Rs=hs o h1 =R+R2+…+R,=∑R 4.串联风路等积孔与各分支等积孔间的关系 vR R,,, 19 1.19 ∑R A ∑3. 总风阻等于各分支风阻之和，即： 4. 串联风路等积孔与各分支等积孔间的关系 = = + +  + = + + + = = n i n i s n s s s R R R R Q h h h R h Q 1 2 1 2 2 1 2 ... 2 2 2 2 1 1 1 1 1 n s A A A A + +  + = 2 1.19 Ri Ai = 2 2 1.19 Ai Ri =   = =  = = 2 2 2 2 1.1 9 1 1.1 9 1.1 9 1.19 1 i i i s A A R R As