So I am having trouble designing pumps
1) I don't have the system curve for pumps so I am providing the data on how do i utilize it to simulate real field pump
DATA:
PUMP TYPE: centrifugal
TOTAL HEAD: 50m
DISCHARGE: 100m3/hr
PUMP INPUT: 160.195kw
SIZE:250*300mm
SPEED:1489rpm
the pumping head the plant is giving is 12m into the main pipeline
2) i have 4 working + 2 standby pumps in parallel
how do i design which pump gets turned on when and
how do i design them in parallel
please help
System head curves can be generated for pumps when you are done with all data input in the model. There appears to be some confusion, what you have shown is pump curve, system head curve can be plotted by right clicking on pump > system head curve.
Here is information on system head curve, for your reference.
Understanding System Head Curves in WaterGEMS, WaterCAD, and SewerCAD
You can model the pumps in parallel as shown below and use controls to decide which pump turns on and at what condition. conditions could be based on tank levels , HGLS or you can create time based controls, e.g. between 8AM to 10 PM pump is ON, else OFF. The sample model 4 has some controls set which you can refer. C:\Program Files (x86)\Bentley\WaterGEMS\Samples
Using Controls, Conditions, Actions and Control Sets in WaterGEMS and WaterCAD
Regards,
Sushma Choure
Bentley Technical Suppport
does this look right? based on the examples in Bentley water gems tutorials system curves are not like its shown in figure
Hello Rahul,
Assuming you have the design head and flow of 50 m and 100 m3/hr respectively, you can setup a design point pump definition where a single head vs flow value is used and the shutoff and maximum values are extrapolated. You can set them in parallel with independent pipes from your source to pump and then to your discharge point.
With this setup, try turning the pumps "On" one by one and check the individual system head curves. If you have tied up your pumps to a single pumping station element then combination pump curves is a great way to see multiple pump curves, efficiency curves, overall efficiency curves, and system head curves to all be displayed on a single graph. This will also help you determine the best possible combination to run the pumps. See this technote which discusses about combination pump curves and solving them for the best pump combination: Pump Station and Pump Combination Curves
Hope this helps.
Yashodhan Joshi