Object: To determine the Coefficient of weir Cw for Sharp-Crested weir.
Introduction to Practical
Apparatus Required:
- Perspex-sided tilting flume S-4; model sharp-crested weir with ventilating tubing; stopwatch.
Theory:
Sharp-crested weir and draw its sketch:
Procedure:
Observations:
t | Q (=Qv =Qu) | Yv | Ventilated air cavity | Un-ventilated air cavity | ||||||||||
hw-v = Yv-P | hwv P | Cw-v 22 | Q 2.6 h3 / 2 wv | Yu | hw-u = Yu-P | hwu P | Q Cw-u 222.6 h3 / 2 wu | |||||||
lit. | cc | s | cc/s | cm | cm | |||||||||
(5) = | (3) | (6) | (13) = | |||||||||||
(4) | (8)= | (7) 12 | (9) = | (5) 222.6x(7)3 / 2 | (5) | |||||||||
(2) | (3)= (2)x1000 | (4) | (7)= (6)-12 | (10) | (11)= (10)-12 | (11) (12)= 12 | 222.6x(11)3 / 2 | |||||||
Plot:
- Cw-v vs hw-v/P
- Cw-u vs hw-u/P
Cw-v
hw-v/P
Fig. 2.1 Plot of Cw-v vs hw-v/P
Cw-u
hw-u/P
Fig. 2.2 Plot of Cw-u vs Cw-u/P
Results and comments:
