2 replies to this topic

[Ghasem.Bashiri]

As you know, there are some different rules for NSPH calculation in services with "dissolved gas". In such cases it is proposed to define composition in process simulation and then set vapor fraction to some small range (e.g. 0.005) to find vapor pressure at a given temperature. 

However, there is not a clear definition for "dissolved gas" concept. 

Methane is dissolved gas in propane, butane and fuel oil based on corresponding phase quilibrium calculation.

Same concept is available for oxygen and nitrogen presence in hydrocarbon fluids.

Therefore, from simulation and EOS points of view, all such light components dissolved in a given phase. But I think from pump and NPSH side, if "dissolved gas" concept is a general rule, some limitation is available for nature of two components to define one of them as dissolved gas on other one. Please advise. 

[Dieguito2]

Dissolved gases are those components that have critical temperatures below the temperature of the system you are modeling. they generally obey to Henry law.

[breizh]

Hi,

Consider the documents attached to support your work .

At the end it's your own judgement .

Good luck

Breizh