测量圆管水流流量的里流量计的流量公式为()。设流量计为水平放置,主管道直径 D ,喉部直径 d ,水银差压计读数 h ,不计能量损失, α =1。
A.
v 1 ={2 gh ( ρm / p -1)/[( D / d )4-1])}1/2, q v =π D 2{2 gh ( ρm / p -1)/[( D / d )4-1]}1/2/4
B.
v 2 ={2 gh ( ρm / p -1)/[1-( d / D )4]}1/2, q v =π d 2{2 gh ( ρm / p -1)/[1-( d / D )4]}1/2/4
C.
v 2 ={ gh ( ρm / p -1)/[1-( d / D )4]}1/2, q v =π d 2{2 gh ( ρm / p -1)/[1-( d / D )4]}1/2/4
D.
v 1 ={ gh ( ρm / p -1)/[( D / d )4-1])}1/2, q v =π D 2{2 gh ( ρm / p -1)/[( D / d )4-1]}1/2/4