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[A_D_M_MII]

Hi everyone,

 

I have the next doubt/question:

 

I have to simulate in Aspen Hysys V.10. a process which contains some HX that I have to simulate in his rigorous model, I have the pressure and temperature that currents should have because I have also the technic sheet which shows the orientated results of the implicated currents.

 

So, with my simulation I have to be near those results, but, there is one of them that it's impossible to achieve.

 

It is a shell and tube HX whose currents should be:

 

Tube IN: Demin water 5 kg/cm2g and 23ºC

Shell IN: Process gas that has already started to condensate water. 146 ºC and 25,3 kg/cm2g.

 

Tube out: Demin water 4,35 kg/cm2g and 95ºC

Shell out: Process gas that is condensating water yet. 126 ºC and 25,1 kg/cm2g.

 

BUT it is impossible to achieve the 25,1 kg/cm2g, the simulation has calculated that there is a pressure drop of 0,02 kg/cm2g, instead of 0,2 kg/cm2g.

 

I have put all the main parameters in his geometry, I have also put the impingement plate, but it always calculates the 0,02 kg/cm2g, has it any physic or chemical explication that justify this low value of pressure drop in order to say that this technic specificatión could be wrong?

Thank all of you!

  ADM

 

[latexman]

Being off 0.18 kgf/cm2g out of 25.1 kgf/cm2g (0.7%) is not worth worrying about in the real world.

And, in Academia, someone may not have typed in a 0, as in 0.2 vs 0.02. Possibly easily explained by human error.

My 2 cents.