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

Propeller Forces CFX

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 15, 2015, 09:46
Default Propeller Forces CFX
  #1
New Member
 
Emric E
Join Date: Apr 2015
Posts: 2
Rep Power: 0
newcon is on a distinguished road
Dear All,
I've looked through these forums and I cannot find a definate answer for my particular set-up:
I've set up my assembly and assigned the propeller to 1000 rpm.
From the monitors I have acquired the mass flow at the outlet (small side) as well as pressures on the propeller's blades in results.
Assembly.jpg

However I am trying to attain the thrust generated on the propeller itself, I have selected in this case the normal force in the fluid in the x axis and achieved a result of -0.93. Is this the value I am looking for? screenshot of the monitor and selection below:
Forces moniter.jpg

Thanks In advance,
Emric
newcon is offline   Reply With Quote

Old   April 15, 2015, 18:24
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
You appear to have modelled the impeller and the duct as a solid. Unless you are modelling FSI or thermal fields you do not do this. You only model the fluid domains.
ghorrocks is offline   Reply With Quote

Old   April 16, 2015, 08:26
Default
  #3
New Member
 
Emric E
Join Date: Apr 2015
Posts: 2
Rep Power: 0
newcon is on a distinguished road
Thank you for the reply,

I had added the impeller as an immersed solid as I thought this would apply sorry my screenshots didn't show, there is a fluid domain within the solid shell.
CFX-Pre.jpg

So do you mean I should change the impeller to be a fluid domain?
Or should I set the impeller wall as an interface.
If so how can I assign rpm and find the torque?

Sorry about what I'm sure are such basic questions.

Regards,
Emric
newcon is offline   Reply With Quote

Old   April 16, 2015, 18:37
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Do the rotating machinery examples in the CFX tutorials. There are quite a few. That will show you how to do it.
ghorrocks is offline   Reply With Quote

Old   July 1, 2015, 17:13
Unhappy ducted prop. analysis with cfx
  #5
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
Hi to all
I modelled a ducted propeller and want to anlysis ansys cfx and defined main domain and propeller as wall in rotating domain but I don't know that how define the duct? When I run solver, it show error.
Help me please?
Tnx.
sohrabmajd is offline   Reply With Quote

Old   July 4, 2015, 08:32
Default
  #6
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Showing what you have modelled, the CCL and the error message would help.
ghorrocks is offline   Reply With Quote

Old   July 4, 2015, 23:38
Default
  #7
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
Quote:
Originally Posted by ghorrocks View Post
Showing what you have modelled, the CCL and the error message would help.
here is my model file and ccl file.

http://www.2shared.com/file/kygPxAmL/ducted_kaplan.html

the error just show that '' Ansys CFX can't run for your solver"
when i run solver for propeller without Duct it show results.
sohrabmajd is offline   Reply With Quote

Old   July 5, 2015, 06:17
Default
  #8
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Can you

The error sounds like you have a fundamental setup problem, and possibly your installation of ANSYS. I have no idea what. I would just start the problem simulation again, making sure you do all the steps correctly.
ghorrocks is offline   Reply With Quote

Old   July 5, 2015, 09:20
Default
  #9
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
Quote:
Originally Posted by ghorrocks View Post
Can you

The error sounds like you have a fundamental setup problem, and possibly your installation of ANSYS. I have no idea what. I would just start the problem simulation again, making sure you do all the steps correctly.
Did you check my model domains and boundaries?
Are thoses correct? Is The ccl file correct?
I run it again but it show warning thay " return value c0000005>ffff in parse_rv, treating as not run."
"An error has occured in cfx5solve that cd2flow.exe aborted for unknown reasons."
And another error show that " the cfx solver for system fluid flow(cfx) did not produce a result file. Detailed information can be found in the output file for the run."
Mr.ghorrocks
Can you say me that how define my model parts (propeller, duct, ... ) as domains(inlet, outlet, opening, ... ) ?
sohrabmajd is offline   Reply With Quote

Old   July 5, 2015, 18:30
Default
  #10
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
No, I did not check your file. I do not download large files and I do not have time to load up your configuration and debug it for you. I can have a look at your configuration if you post the CCL by itself. My comment was based on the strange error message you reported seeing - I have only seen error messages like that when the CPU type selection for the CFX executable is wrong. This is an installation/computer setup problem.

The error messages you report now are more normal. These error messages are usually generated when the simulation has invalid CCL.
ghorrocks is offline   Reply With Quote

Old   July 5, 2015, 18:47
Default
  #11
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
Thanks because of your answers.
It's not large file.(1.19 mb)
The zip file has my ccl file .
When I run a prop. Without duct, it run solver and show me results. But when ducted propeller runs, show errors.
I think that my problem is in define domains with duct.but I don't know that how solve it.
sohrabmajd is offline   Reply With Quote

Old   July 6, 2015, 00:46
Default
  #12
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
You are modelling the solid as a CHT solid (which means heat transfer), yet your fluid is isothermal (which means no heat transfer). This will cause a problem.

There is no need to model the solid as a CHT solid. Just leave it as a cut-out in the mesh.
ghorrocks is offline   Reply With Quote

Old   July 6, 2015, 00:55
Default
  #13
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
But how can I change the solid type?
I just modelled it in solidworks and import it into ansys as a frozen.
Is there any way to change solid type?
sohrabmajd is offline   Reply With Quote

Old   July 6, 2015, 06:18
Default
  #14
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
No, you don't change the solid type. You remove it completely. There is no need to model it. In designmodeller or ANSYS mesh just suppress the solid part.
ghorrocks is offline   Reply With Quote

Old   July 6, 2015, 07:04
Default
  #15
New Member
 
Join Date: Jun 2015
Posts: 29
Rep Power: 10
sohrabmajd is on a distinguished road
Quote:
Originally Posted by ghorrocks View Post
No, you don't change the solid type. You remove it completely. There is no need to model it. In designmodeller or ANSYS mesh just suppress the solid part.
Oh...I understand.
But I just did suppress body for propeller. I saw it at thread "underwater propeller cfd analysis with ansys cfx" tutorial.swf file that Mr. Alaeddine sent its link for download.
So now, should I suppress propeller and duct together??
sohrabmajd is offline   Reply With Quote

Old   July 6, 2015, 07:13
Default
  #16
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,703
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
If you don't care about the temperature field inside the duct then yes, you suppress that too.
ghorrocks is offline   Reply With Quote

Reply

Tags
ansys, cfx, forces, propeller


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Forces in OF15 richard OpenFOAM Running, Solving & CFD 180 July 9, 2018 10:54
Underwater Propeller CFD analysis with Ansys CFX Alaeddine CFX 7 March 30, 2018 01:37
Pressure and density values to compute forces fernexda OpenFOAM Post-Processing 2 March 6, 2015 03:39
Forces for airfoil test case Martin_ OpenFOAM Running, Solving & CFD 1 July 2, 2012 11:58
RE: Applying forces / Center of Gravity in CFX Janusz CFX 1 November 16, 2008 19:37


All times are GMT -4. The time now is 20:31.