I need estimate the pressure in impermanent regime due to the fall a pump when this started to operate (Shut Down)

Hello Felipe,

Are you modeling a pump shut down in HAMMER? If that is the case, you would want to set the Transient Pump Type in the pump properties to "Shut Down After Time Delay". There are a couple of sample models that model a pump shut down event. These samples can be found at C:\Program Files (x86)\Bentley\HAMMER8\Samples. Sample models that have a pump shut down include Sample2.wtg, Air_Valve_Example.wtg, and Hydropneumatic_Tank_Example.wtg. In these samples you can see the general setup for a pump shut down event.

There are a number of sources that might be useful for you when using HAMMER. Our TechNotes and FAQs page have a number of topics on HAMMER, including on the protection devices HAMMER uses. The HAMMER V8i FAQ has a lot of good general information on using HAMMER and viewing results.

Regards,

Scott 

Hello Regards

I need estimate the pressure in impermanent regime due to the fall a pump (SHUT DOWN), but in the moment when this started to operate. Then, when the pump is close to find its operation point, occurs the shut down. It's model is different from modeling only a shut down.

Felipe.

Hello Felipe,

If I am understanding the issue correctly, you want to model a pump starting up and then have it shut down again after it reaches its operating point. There are a couple of ways that you can model this. The first would be using the "Pump Start - Variable Speed/Torque" option for the Transient Pump Type. This allow you to enter an operating rule with the pattern that the pump will follow. The pump will start in the Off position for the initial conditions. You will need to enter a nominal head and flow value that the program can use to identify the pump curve that will be used. The operating rule can also include the pump shutting down again, so the pump start up and shut down can occur in a single scenario. You can find details on modeling a pump start up at the following link: communities.bentley.com/.../3276.modeling-a-pump-start-up-transient-event-in-bentley-hammer-v8i-tn

Another possible solution would be to model the pump start up and the pump shut down in separate scenarios. If the pump will be on long enough that an transient from the pump start up will have dissipated, this would be a suitable operating case. You would model the pump start up in one scenario and analyze the results. In another scenario, you would model the pump shut down.

If this doesn't help with the issue, I will need some additional details on what you are trying to model.

Regards,
Scott