2 replies to this topic

[zfreddyzzz]

Hi,

I have a quick question related to HYSYS.

I was designing a heat exchanger using the steady state rating.

I have all my calculations done and the only thing that is not clear is the tube length input in HYSYS.

Not much information was provided concerning that. so my question is:

- for the tube length would you insert the length of the exchanger or the length of the tube.

for example...based on the calculations I need a 20 m long tube. but we know, based on the recommendations the heat exchanger length should fall between 4 - 6 m.

so if I input a 20 m long tube in HYSYS, and change the number of tube passes into 4 would that be counted as a 5 m actual length of the exchanger?

or the way I have to input it is a 5 m tube with 4 tube passes, this way HYSYS will take it as a 20 m long tube that is bended.

I would appreciate any input on this point.

Regards,

Freddy

[joerd]

Tube length is really the length of the tube. So in your case, input 5 m length, 4 passes.
You are probably aware that Hysys is not an exchanger design program like HTRI or HTFS. The rating results from Hysys will differ from HTRI, and I'd trust HTRI any day over Hysys in this respect. Therefore, I have only used Hysys for rating after checking the results with HTRI, to be able to simulate the whole process without going back and forth to HTRI.

[jcazenave]

The alternative is to use EDR (new name for HTFS), within the HX unit op from HYSYS. This will allows you to model the rigorously the heat exchanger without having to leave the HYSYS environment.

Kind Regards