Question

In a 100 mm diameter horizontal pipe a venturimeter of 0.5 contraction ratio has been fixed. The head of water on the meter when there is no flow is 3 m (gauge). Find the rate of flow for which the throat pressure will be 2 meters of water absolute. The coefficient of discharge is 0.97. Take atmospheric pressure head = 10.3 m of water.

Answer 1

00000.123 coordinator position

Answer 2

Answer:

29.303 lit/sec

Explanation:

Dia of pipe.

:- Area,

Dia at throat,

.: Area,

Head of water for no flow

Throat pressure head

d, = 100 mm = 10 cm

TC d= (10) 78.54 cm? a = - 4 !! 4

d 0.5 x d, = 0.5 x 10 = 5 cm

TO 4 (5)* = 19.635 cm

= 3 m (gauge) = 3 + 10.3 13.3 m (abs)

= pg

= P2 = 2 m of water absolute.

pg

: Difference of pressure head, h = - = 13.3- 2.0 = 11.3 m = 1130 cm

P8 pg

Rate of flow. Q is given by Q = C,

= 0.97 x

Vai - až

x 2gh

78.54 x 19.635

(78.54) - (19.635)

2227318.17

76

6.7.2 Orifice Meter or Orifice Plate.

x2 x 981 x 1130

= 29306.8 cm/s = 29.306 litres/s. Ans.