This ppt gives information on water flow measurement techniques

1. Measuring Flow of water

2. Cross section of a Water source
• The following image shows a cross section of a
river stream

3. Measuring float
• Float method
Following method is explained in the slide given
next

4. Measuring flow
From figure in previous slide
We need to
• Calculate the average depth of stream
• Calculate the width of stream
• A piece of wooden/cork material
• Select a straighter area of stream/river/canal

5. Measuring flow
After calculating depth and width
• Now float a small rubber piece on river
• With stop watch measure time taken
• This will be the length

6. Measuring Flow
• Now you know length,width and distance
covered
• You know the time taken by floating rubber
• Now use formula for volume
Volume = length x breadth x depth
You can find out how much cubic meter volume
water flows in one second
Detailed image shown in next slide

7. Measuring flow
• Please refer the following figure
Point A and point B in figure is length
You have width
You have depth
You have time taken
from point A to B
Using formula,volume can be calculated

8. • Distance travelled by object from point A to B
will be the distance
• We have time
• Distance/Time = surface velocity
• Average velocity = surface velocity x 0.85
Usually mean of surface velocity factor comes to
0.85

9. • Now you have average velocity
• Now calculate area of cross section
• Types of area
1) Rectangular 2) Trapezoidal

10. Calculating surface areas
• Rectangular area