7 replies to this topic

[lucymaomao]

Hi, dear everyone! I have been using hysys for a while, but all are in the steady state. Right now, I need to transfer to dynamic, which Ｉ have tried for several weeks and have no idea that in which way I should do, I really hope some friend with experience can give me some advices.

I uploaded my steady state profile, the process is to make di-methyl ether from 2 MeOH. a PFR reactor with one distillation column to separate the DME product and another one to get the MeOH for recycle.

I have many confusion when I use the dynamic assistant to move to the dynamic environment, everything changed a lot, and since hysys uses the pressure driven method, I have no idea how to make the pressure right, I am trying to adjust the energy stream ( I found this is the only place that I can change in dynamic ) to make the system to be stable, but I failed after one week adjusting, and I think my way is not right.

So how to do the dynamic simulation, I am thinking of breaking the process into two parts, or ?

should I adjust in dynamic or in steady state? How to check the pressure is right when transfer to dynamic? and How to do the equipment sizing like for the valve and pump to make them work welll in dynamic?

I know I asked a lot, just because I am really lost in the dynamic simulation, I do hope someone can gave me some advice or clue for doing the dynamic simulation, thank you so much !

Thanks！！！！！！！！

[Dacs]

I think it's imperative for you to at least give us a sketch of the process concerned.

In that way, we can figure out what you're trying to ask

[Technical Bard]

I would recommend enrolling in an Aspentech Dynamic simulation training course. While steady state simulation is relatively each for a chemical engineer to pick up on their own, dynamic simulation is a very different animal, and each dynamic simulator has it's own distinct differences in how you set up a model and run a model.

With HYSYS Dynamics, my experience is that it is often easier to build dynamic models from scratch, rather than converting a steady state model.

[lucymaomao]

Thank you all for giving me the suggestions, thanks !

I really want to show you my process, but I can not upload my .hsc file? I do not know why, maybe my ID is too new?

[samrat]

Import your *.hsc file in "xml". Then everybody can see the folder. I think this has been discussed in many other forum discussions.
samrat

[Stefano]

As yet said by Technical Bard it is very difficult to convert a steady state model to a dynamic model.
Just an indication: when you build a dynamic simulation every border stream must be determined in flow or in pressure (you can change the color scheme in Dynamic P/F spec and you will see a green stream if you put the pressure value, yellow stream if you put the flow value, red stream if you put flow and pressure values together).

[jmukund]

Hi lucymaomao,

The Staedy state simulation is just basis for dynamic simulation, you need lot more things like design data for valve,exchanger, vessel, columns including elevation and control philosophy for your plant.

As mentioned in prior posts it is convinient to start from scratch instead converting from steady state. It needs lot more efforts than steady state.

[anuragsharma23]

Send me ur File on bananashake1997@gmail.com and than we can discuess.