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[hazmee]

i'm attaching the simulation in hysys that i've done.

when i start the integrator, the both fluid that coming into the pump and compresor is not equal to 0 and 1 respectively..

so here is my question:

a) what kind of spec that i have to spec in making the fluid coming in to the compressor is only gas and the fluid coming into the pump is only liquid.

can anyone comment on my sim. and in the real situaution, if this happen, what should we do?



regards and thank you.

hazmee.

Attached Files

•  dynamic_sim_for_pump_and_compresor.zip   88.7KB   86 downloads

Dear Hazmee:

Concerning your Hysys model, I have following questions:

1. How do you decide the Cv value of each Valve?
2. How do you decide the duty and efficiency of Pump and compressor?
3. How do you build your Dynamic model?

Actually those value should be obtained from steady state simulation, that is the reason why we normally build the Dynamic model from the base of steady state model. Problem for your model is that liquid level of separator can not be maintained, it means the Cv value of valve and Pump and compressor duty and eff is not properly set. So my suggestion is as below:

1.Build steady state Hysys model first, decide the pressure drop for each valve,and proper duty and efficiency of pump and compressor to meet the requirement of each discharge pressure.
2. Then transfer the steady state model to dynamic model, carefully select the action of each controller and gain and Ti. (note: in your current model, the action of LIC is wrongly set as reverse action, and Ti of FIC is left empty) Fine tuning of each controller is also important to ensure the stable operation of model.

If any further question, pls don't hesitate to ask!

best regards,
P.Wang