Hydraulic Gradients

Question 1

Draw a hydraulic gradient, with the relevant equation on the Y and X axis.

Answer 1

Question 2

When pumps are in series, how can the residual head be implemented into a gradient diagram?

Answer 2

• Pumps in series have a cumulative pressure effect.
• Therefore, by adjusting the first pump, the RH can be accounted for at the start.

Question 3

What should the residdual head be at the start and end of a ‘pumoing’ gradient?

Answer 3

10m at start

1m at end

Question 4

When do pump siphons occur?

Answer 4

When the ‘pump’ gradient goes through the pipe gradient.

Question 5

What are some remedies to system siphons?

Answer 5

• Break tanks
• Install another pump to overcome the siphon
• Increase pipe diameter - thuis reducing velocity but increasing head.
• Move the pipe
• Bury the pipe
• Worst case - fit an anti siphon valve