CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > CFX

convergent_divergentnozzle

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   March 21, 2009, 05:23
Default convergent_divergentnozzle
  #1
Member
 
sivaramakrishnaiah
Join Date: Mar 2009
Location: india,pondicherry
Posts: 74
Rep Power: 8
sivarama1 is on a distinguished road
Send a message via MSN to sivarama1 Send a message via Yahoo to sivarama1 Send a message via Skype™ to sivarama1
i am also simulating convergent and divergent nozzle,
1) In CFX-11,Two region of flows how should analysis actually,take
convergent and divergent nozzle (in convergent is subsonic and
divergent is supersonic)
1)subsonic
2)supersonic
in two region in single model (that means convergent and divergent
nozzle in a single geometry in that in that i will give boundary
condition inlet of convergent pressure 15 bar steam, throat of
pressure 8 bar outlet of 1 bar pressure)
i know inlet velocity of steam 856 m/s this is saturation steam.
How will analysis in CFX-11,as a hypercritical point of correct
results came,but i should verified in CFX-11 SOFTWARE analysis,please
let me know.
once again thankyou for replay.
,i am sending .rar file,please verify it,
in that CFX,and ICEM files.
Actually i done same process,but solution not converging
Geometry:combined of convergent and divergent nozzle.
Converging and diverging nozzle flow problem
My doubt,this model i was created in UNIGRAPHICS modeling
software,meshing ICEM CFD,
when ever i am giving analysis:at that time some problem is there
step2:Boundary condition
Fluid :Steam
mass flow rate:0.5 kg/s
at inlet of convergent nozzle:subsonic condition a)pressure=10
bar;Temperature:356 m/s
at outlet of Divergent nozzle :a)supersonic condition .
You told this type of settings and simulations given by tutorial 8
from ANSYS CFX release 11.0. in this different : inlet is supersonic
condition outlet also supersonic condition
but my point of view inlet is subsonic and outlet is supersonic condition
1)i was increased mesh size
2)That flow direction changed
3)Fluidry steam taken
4)Same boundary conditions
But does not converging(up to 200 iterations converging),what i am
thinking know up to convergent portions was converged.after that it
is not converging,)
convergent nozzle:solution converging .
Divergent nozzle:solution not converging as per velocity plot.and pressure plot.
Actually pressure should drop and velocity should increases.but in
this condition;
1)convergent to throat :velocity increases and pressure droping
2)Throat to Divergent nozzle:Velocity not increasing and pressure not droping.
What is the problem. i am thinking Two solutions(means subsonic and
supersonic condition will not give in single solution) that is correct
or not,please verify that.
Thank you very much.
__________________
sivaramakrihnaiah
__________________
sivaramakrihnaiah
sivarama1 is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 04:40.