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enter image description here As you can see the figure, I gave outlet boundary condition as 20 bar. Actually I want the compressor to calculate the pressure outlet by using pressure ratio.

Can we model a system using fluid libray without outlet boundary condition?

marco
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YEKAMBARAM RENTAMALLU
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1 Answers1

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If you just remove sinkP the system will be underdetermined — you'll miss one boundary value. Since the compressor models describe the relationship between pressure difference and mass flow rate you must specify the mass flow rate if you want the model to calculte the outlet pressure. To do so, use a mass flow rate/enthalpy (or temperature) as outlet boundary component instead of sinkP. Remember to specify a negative mass flow rate.

Rene Just Nielsen
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  • Thank you for your comment. As I have given the parameter to calculate pressure. Is it possible to have the component without outlet boundary condition? – YEKAMBARAM RENTAMALLU Mar 31 '22 at 07:52
  • No. If you don't connect an output boundary component your Modelica tool will assume that no flow leaves the component, thus m_flow==0 and the outlet pressure will be equal to the inlet pressure. – Rene Just Nielsen Mar 31 '22 at 08:28
  • Even if we add a boundary, the pressure, mass flow rate and enthalpy of the compressor be accessed for another component? – YEKAMBARAM RENTAMALLU Mar 31 '22 at 09:24
  • Yes, unless the variable `m_flow` (?) inside the compressor model is marked as `protected` it can be accessed from other components, e.g. by `compressor1.m_flow`. – Rene Just Nielsen Mar 31 '22 at 10:04