11 replies to this topic

[chasib]

Hi All,

Does any one help to know how coluld I calculate the two phase velocit by using hysys (Version 8.6)

 

 

Many Thanks & Regards,

[Bobby Strain]

What have you tried?

 

Bobby

[serra]

it depends,

if you can assume homegeneous mixture (vapor and liquid tarveling at same velocity)

you can simply calculate specific volume (for the homogeneous mixture)

then velocity = mass flow * specific volume / area

most simulators give these values as output,

the software which I use (Prode Properties) has the method StrV() which returns the specific volume for the homegeneous mixture and the solution is mmediate if you use, tools as  Excel,

if I remember correctly Aspen Hysys returns these values as output (or you can sum up the different components)

Differently, if you can't assume homogeneous then simulators may report the different velocities (as output) or slip ratios (velocity ratio) for the different phases, note that different models may return very different values...

Edited by serra, 07 August 2016 - 10:42 AM.

[Pan Nata]

Just use "pipe segment". That's way not only for hysys 8.6 version but may also be applied in hysys later version.

 

 

~Good luck~

[Bobby Strain]

What is the purpose of your question? Maybe you need to ask a different question.

 

Bobby

[chasib]

My Questions,

I want to calculate the tow phase velocity downstream of the control valve to avoid th erosional velocity by using hysys ,and compare the result with my excell calculation.

 

actullay I used the pipesgment ,but I got two velocity one for liguid and the second for the vapour not velocity for mixture ?

 

I hope that will be clear BOBBy

 

Many Thanks For Your Time

[gegio1960]

https://en.wikipedia...as–liquid_flow)

[Pan Nata]

Dear chasib,

 

you can check on hysys as following picture: 

 

 screen shoot.jpg   72.85KB   16 downloads

 

good luck,

[chasib]

Dear Pan,
I was so confusing with this,
bulk velocity=two phase velocity ,thanks for your clarification
And I have another issue,If I want to calculate the pressure drop across flex line in two phase regem
Should I keep the default equation in hysys ?
If no,what is the proper equation for this issue??

Many Thanks ,

Chasib

[breizh]

Hi ,

Consider this excelsheet to support your work.

Hope this helps

 

Breizh

[chasib]

Thank you ,I will try it

 

Chasib

[Pan Nata]

Dear Pan,
I was so confusing with this,
bulk velocity=two phase velocity ,thanks for your clarification
And I have another issue,If I want to calculate the pressure drop across flex line in two phase regem
Should I keep the default equation in hysys ?
If no,what is the proper equation for this issue??

Many Thanks ,

Chasib

 

Chasib,

 

I don't think hysys need to write as two phase velocity, if you deal with two phase fluid then you will get two phase vel.

 

many consideration to decide proper pressure drop correlation in two phase fluid, different guy different satisfaction.

 

However many great expert here already discussed about that and you can search the topic in this forum for your references.

 

Good luck,