CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > CFX

upwind vs high resolution

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

LinkBack Thread Tools Search this Thread Display Modes
Old   January 23, 2006, 04:31
Default upwind vs high resolution
Posts: n/a
I am running a simulation on a pump. While using the upwind model, i get a pressure diffenences of 3000pa between inlet and outlet. When i switch to high resolution, i only get 1000pa of differences. What causes the big differences. In fact i was hoping for a pressure differences of more than 3000 pa, not less while switching to the high resolution setting. Pls help. Any advices is welcome.
  Reply With Quote

Old   January 24, 2006, 21:42
Default Re: upwind vs high resolution
Posts: n/a
Many factors will affect your solution. However, upwind scheme is not accurate. Often it will end up with faulty solution. I normally use upwind to get some quick solution that can be used as an initial condition in high order scheme.
  Reply With Quote

Old   February 16, 2006, 12:05
Default Re: upwind vs high resolution
Posts: n/a
hi, how do you posttreat your job? do you use the massflowave? You have to use results of upwind scheme to obtain more quikly a solution with high resolution advection scheme. The upwind adv scheme consist in putting beta value at 0 (second order effect are neglect). Are you french? If yes, it could be easier to speak french when you are going to gie me an answer.
  Reply With Quote

Old   February 20, 2006, 06:35
Default Re: upwind vs high resolution
Posts: n/a
Hi, The major difference between upwind scheme and the high resolution scheme is that: When we are not usre about the boundary conditions which we got from the test results and accuracy is not a criteria and need of fast convergence we normally use upwind scheme, where as the high resolution scheme we use that when we are confident about the boundary conditions and accuracy is a constraint which we need we ll use the high resolution scheme.

Comming to the post treat use the massflowave to prost process the variable so that you ll not find much variation when compared to areaave.

Regards Badrinath
  Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
High Resolution (CFX) vs 2nd Order Upwind (Fluent) gravis ANSYS 3 March 24, 2011 02:43
about upwind and high resolution Eric CFX 1 December 30, 2006 06:56
high resolution or upwind erick CFX 2 March 9, 2006 00:09
Multicomponent fluid Andrea CFX 2 October 11, 2004 05:12
Upwind vs High Resolution Liwau CFX 2 April 20, 2004 11:49

All times are GMT -4. The time now is 03:18.