I have a sytem with 5 recip compressors. The first stage of each compressor uses 2 of the cylinders, so I need to create a double hung bottle. One of the performance runs indicates that the machines will be run in a single acting condition; and therefore, I am going to need a two chambered bottle with a choke tube in between the chambers separating the cylinders. Since you cannot have a node connect to 4 points in PULS, how do you model this type of bottle?
The approach I used was to add a tee with minimal distance between nodes so I could add in the no flow region using an equivalent diameter (the ID of the bottle less the OD of the choke tube). But, I am not sure if this is an accurate portrayal of reality. I looked at the models that come with PULS in the Bentley file, but I wasn't able to determine how they were creating a mutli-chambered design.
I also need to have a side stream. That is, I have an interstage system where coming into the suction bottle there is the discharge from the previous stage and another process stream. It would be analogous to a Y in a river. Two different gas compositions coming together at a tee to form a new, third gas composition. As of yet, I can only change the pressures, temperatures, and flows of individual pipes, but the gas composition is constant throughout the entire model. Is there a way to have multiple gas compostions in the same model?
Any help or modelling advice is appreciated.