simscape centrifugal pump (IL) flow rate error

Hi,

I am currently trying to model the charging and discharging of a ship ballast tank. I have modelled the charging system and discharge system seperatly and I am at the stage of simulating each system before brining them together.

I have been stuck on simulating the charge system for some time now due to some errors with the centrifugal pump. an error I keep getting is:

at time 0.00... one or more assertions are triggered.

• pump is operating outside of nominal region. Pump flow rate is either larger than maximum capacity or is less than zero.

Along with this error, I have negative or very low (1e^-5....) flow rate in a flow rate sensor positioned after the pump, but no matter what parameters I change I can't get rid of the error or obtain a substantial flow rate?

all help is appreciated:)

Answer 1

[Aishwarya Shukla]

Hi @ Aiden ,

It sounds like there might be a problem with the parameters you are using for your centrifugal pump. The error message you are receiving suggests that the flow rate is either exceeding the pump's maximum capacity or falling below its minimum threshold.

Here are a few things you can try to resolve the issue:

1. Check the pump specifications: Make sure that the maximum and minimum flow rates you have specified for the pump are accurate. If you have a data sheet or manual for the pump, double-check these values. If not, you may need to contact the manufacturer or do some testing to determine the correct values.
2. Check the pump curve: Centrifugal pumps have a characteristic curve that relates flow rate to head (pressure). Make sure that the flow rate you are specifying falls within the pump's operating range on the curve. If it doesn't, you may need to adjust the pump speed or impeller diameter to get the desired flow rate.
3. Check the inlet conditions: Make sure that the pump is receiving an adequate flow of fluid from the ballast tank. If the inlet flow rate is too low, it can cause the pump to operate outside of its nominal range.
4. Check for leaks: If the pump is not able to generate enough pressure to move fluid through the system, it may be due to leaks in the piping or fittings. Make sure that all connections are tight and that there are no leaks in the system.
5. Check for cavitation: If the pump is operating at a flow rate that is too high for the system, it can cause cavitation, which can damage the pump and reduce its efficiency. Make sure that the flow rate is not causing cavitation to occur.

I hope these suggestions help you resolve the issue and get your simulation running smoothly.

[Aiden]

Thank you Aishwarya, this really helped me understand the pump better ! got it working