Pump Curve design

In Water Module, there are 2 types of pump can be used;

1. Constant Power
2. Pump Curve

Pump is used to increase/boost the Residual Pressure to reach the minimum required but not exceeding the maximum pressure allowed where as in other word to kept the pressure within range. User may constructively add a pump to their water reticulation network system. However the design of water reticulation network system depends on how user allocates the pump location and how the design will be constructed.

The principle output parameters are flow(LPS) and head(m) gain.

However, this guideline will be focussed on how to use  ‘Pump Curve’ in water reticulation network system. Image below shows a ‘Pump Curve’ properties:

How to Use a Pump Curve in a water reticulation network #

1.Please go to Water >> Input >> Pipe >> Spread Input >> Pump & Valve

Click at the three dot button and a pump/valves dialog pop up

2. As you can see image below, Residual Pressure for Node 21 is less than the minimum pressure which is 7.5 m.

3. Hence, in order to push the pressure up above the minimum pressure allowed, there will be a pump located at  node 3.(this is because previous node is 3, pipe 3 is from node 3 to node 21)

4. Here is the most critical part where the pump curve properties for Flow(LPS) and Head(m) is taken into consideration. To determine the value of the flow and head to be input at the pump properties, you may have to use the flow result generated previously. (please refer to the flow at >> Result >> Analysis Output >> Pipes for Peak Calculation)

5. Referring to the image attached above, the pipe no 24, Node 21 to node 17, the flow is 17.954 LPS. Hence, at the pump properties, the LPS should be input to make the flow at Pipe no 24 is within range.

6. Therefore, the input data is as follows;

7. Then , you may proceed to analyse. Now you can check that the Residual Pressure at node 21 is pump up and it is now more than 7.5m. (please refer image attached below)

How to check the residual pressure manually #

Example

Pipe no.3 (node 3 to node 21)

Before pump is applied GL : 34.04 m HGL : 41.49 m HSL : 34.04 m RP : 7.45 ( < 7.5 m) design fail

After pump applied at Node 3 GL : 34.04 m HGL : 41.93 m HSL : 34.04 m RP : 7.89 ( > 7.5 m) design passed   Manual Calculation RP  = HGL – HSL = 41.93 m – 34.04 m = 7.89 m   How to get HGL = 41.93 m? *we have to take note that the HGL at every nodes is related and dependable at the previous node, for node 21, the HGL for node 21 will depends on HGL at node 3 and the head loss at node 3. *therefore, HGL (node 3) = 41.16 m Head Loss (m) = – 0.7605 m   Hence, HGL at node 21 = HGL – Head Loss = 41.16 m – (- 0.7605 m) = 41.93 m   *Head Loss in negative value means that the pressure is restore instead of losing it.