[
Sponsors
]
Home
News
Index
Post News
Subscribe/Unsubscribe
Forums
Main CFD Forum
System Analysis
Structural Mechanics
Electromagnetics
CFD Freelancers
Hardware Forum
Lounge
Software User Forums
ANSYS
CFX
FLUENT
Meshing & Geometry
Autodesk
AVL FIRE
COMSOL
CONVERGE
Fidelity CFD
FloEFD & FloTHERM
FLOW-3D
OpenFOAM
News & Announcements
Installation
Meshing
Pre-Processing
Solving
Post-Processing
Programming
Verification & Validation
Community Contributions
Journal
Bugs
Phoenics
REEF3D
News & Announcements
Siemens
STAR-CCM+
STAR-CD
SU2
News & Announcements
Installation
Shape Design
Pre-processors
ANSA
enGrid
GridPro
Pointwise
Post-Processors
EnSight
FieldView
ParaView
Tecplot
Special Topics
Mesh Generation
Visualization
CFD Online Community
Site News
Site Help & Discussions
CFD-Wiki
Wiki
Introduction
Recent Changes
Reference Section
Fluid Dynamics
Turbulence Modeling
Numerical Methods
Meshing
Special Topics
Aero-Acoustics
Combustion
Parallel Computing
Turbulence
Application Areas
Aerospace
Automotive
Turbomachinery
Best Practice Guides
Automotive CFD
Turbomachiney CFD
Heat Transfer CFD
Validation Cases
Codes
Source Code Archive
FAQ's
Ansys
CHAM
CONVERGE
Fluent
Metaconp
MeteoDyn
Siemens
History of CFD
About CFD-Wiki
Help
FAQ
Getting Started
Community Portal
Donate Texts
Donated Texts
Links
What's New
Introduction
Modeling & Numerics
Turbulence
Combustion
Discretization Schemes
Solvers
Multigrid Methods
Finite Element Methods
Cartesian Methods / AMR
Numerial Analysis
Mesh Generation
General Resources
Selected Projects
Companies
Programming & Dev.
Data Formats
Software Libraries
Numerical Software
Parallel Computing
General Sites
Software
Fluid Dynamics
Mesh Generation
Visualization
Commercial CFD Codes
Hardware
Benchmarks
News and Reviews
Hardware Vendors
Clouds
Clusters
GPGPU
Misc
References
Validation Cases
Airfoils
Material Properties
Glossaries
Finding Documents
Preprints Online
Papers & Reports
Books
Journals
Publishers
Online Tools
Unit Converters
Calculators
y+ Estimation
Compressible Flow
Heat Transfer
Airfoil Generators
Simple Cases
Combustion
Cycles & Processes
Online Books & Guides
CFD Introductions
Books
Best Practice Guidelines
Fluid & Aero Dynamics
Seminars
Encyclopedias
Social Media
Discussion Forums
Blogs
Twitter
YouTube
Facebook
LinkedIn
Podcasts
Usenet Newsgroups
Mailing Lists
Chats
News
Education
CFD Programmes
Online Labs
Online Courses
Course Material
Jobs
CFD Job Resources
Companies & Orgs.
General Resources
Events
Event Calendars
Specific Organizations
Vendor Events Lists
Misc
Pictures and Movies
Fun
Links to Links
Suggest New Link
About this Section
Jobs
Post Job Ad
List All Jobs
List Jobs by Type
Job in Industry (23)
Job in Academia (50)
PostDoc Position (37)
PhD Studentship (64)
Internship (3)
Diploma Work (2)
List Jobs by Location
Asia
China (19)
India (17)
Israel (2)
Malaysia (2)
South Korea (2)
Taiwan (1)
Thailand (1)
Turkey (1)
Europe
Austria (6)
Belgium (3)
Czech Republic (3)
France (24)
Germany (16)
Ireland (1)
Italy (4)
Netherlands (6)
Norway (2)
Russian Federation (1)
Spain (1)
Sweden (4)
United Kingdom (16)
North America
Canada (4)
United States (39)
Oceania
Australia (1)
New Zealand (1)
South America
Brazil (1)
Chile (1)
Search Job Ads
Events
Post New Event
List All Events
List Events by Type
Conferences (5)
Workshops (3)
Courses (1)
Online Events (5)
List Events by Location
Africa
Algeria (1)
Asia
India (2)
Europe
France (1)
Germany (2)
Italy (1)
Montenegro (1)
Sweden (1)
North America
United States (3)
Oceania
New Zealand (1)
Tools
RPN Calculator
Scientific Calculator
Unit Conversion
Y+ Estimation
Turbulence Properties
Feeds
News
Blogs
Vendors
Jobs
Journals
About
About CFD Online
Privacy Policy
Contacts & Feedback
Web Server Statistics
List of Sponsors
Advertising on this Site
Search
Home
>
Forums
Blogs
Recent Entries
Best Entries
Best Blogs
Blog List
Search Blogs
Search Results
User Name
Remember Me
Password
Register
Blogs
Members List
Search
Today's Posts
Mark Forums Read
Showing results 1 to 18 of 18
Search took
0.00
seconds.
Search:
Posts Made By:
ghorrocks
Forum:
CFX
August 25, 2013, 20:39
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
No problem Alex, glad for the help. Yes, this...
No problem Alex, glad for the help. Yes, this thread has become a bit of a fluid mechanics lesson.
The choice of boundary condition is driven by what most closely matches your experimental...
Forum:
CFX
August 22, 2013, 20:32
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
Do a simulation of flow in a laminar pipe, at say...
Do a simulation of flow in a laminar pipe, at say Re=500 (so well laminar) and have a look at how the flow develops.
In turbulent flows it is hard to see the details as it is lost in the...
Forum:
CFX
August 21, 2013, 19:40
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
:) The diagram you show is wrong. The person who...
:) The diagram you show is wrong. The person who drew that diagram does not understand the details of how fully developed flow forms.
You haven't thought about it yet - how does the flow in the...
Forum:
CFX
August 21, 2013, 01:36
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
Have a think about it - the flow in the centre...
Have a think about it - the flow in the centre needs to go faster than the initial plug flow in the fully developed flow. So how does it "know" it needs to accelerate?
If the thought experiment...
Forum:
CFX
August 20, 2013, 20:35
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
If you start a flow with plug flow (ie constant...
If you start a flow with plug flow (ie constant velocity across the whole section) and allow it to develop into fully developed flow, have a think about how it progresses through the development. You...
Forum:
CFX
August 20, 2013, 20:07
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
1) Mass flow at inlet or outlet - put it where it...
1) Mass flow at inlet or outlet - put it where it best represents the flow you are modelling. You can correct in saying that by default it assumes a constant velocity across the section so that will...
Forum:
CFX
August 14, 2013, 18:45
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
It is the global conservation of that variable....
It is the global conservation of that variable. The residual is the accuracy the equations are being solved in that specific control volume.
No, there is not a general rule that 1% is good enough....
Forum:
CFX
August 14, 2013, 04:34
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
have a look at the imbalances under the solver...
have a look at the imbalances under the solver manager. Get the available variables up by right clicking on a graph window and select imbalances.
Forum:
CFX
August 12, 2013, 07:20
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
The criteria for mesh refinement is until the...
The criteria for mesh refinement is until the variables of interest to you have converged sufficiently to an accuracy you are happy to accept. Any convergence issues which come up you just have to...
Forum:
CFX
August 12, 2013, 03:46
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
You do not need to do a time step independance...
You do not need to do a time step independance check for a steady state simulation. The residuals, imbalances and/or the stability of variables of important to you (eg drag coefficient, pressure...
Forum:
CFX
July 31, 2013, 19:57
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
Please post images directly on the forum, don't...
Please post images directly on the forum, don't hide them in word documents. Also a graph comparing one profile directly to another would be useful.
Before going into the details of turbulence...
Forum:
CFX
July 28, 2013, 08:44
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
y+ is a variable available in the post processor....
y+ is a variable available in the post processor. No need to calculate anything.
Forum:
CFX
July 27, 2013, 08:12
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
I just tried to find the discussion on this in...
I just tried to find the discussion on this in the documentation but could not find it.
Now you have performed the analysis I would look at the y+ it produced and see what you actually got rather...
Forum:
CFX
July 26, 2013, 01:41
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
It gets very tricky for low Re and laminar flows....
It gets very tricky for low Re and laminar flows. So the easiest way is to just look at the results from an existing model and estimate from that. But if you are asking what boundary layer resolution...
Forum:
CFX
July 25, 2013, 22:10
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
This equation is for fully developed high Re...
This equation is for fully developed high Re turbulence flows. You have a low Re flow, it is only just turbulent. So you need a finer mesh as Alex says. And I have already explained twice on this...
Forum:
CFX
July 25, 2013, 09:00
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
If you plot conservative values you will find...
If you plot conservative values you will find they do not go to zero. This is because they show the velocity at the centroid of the control volume, and these centroids lie off the wall - so they are...
Forum:
CFX
July 25, 2013, 03:26
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
Have a look at hybrid and conservative variables...
Have a look at hybrid and conservative variables in the documentation and post processor.
Forum:
CFX
August 24, 2011, 19:39
Replies:
45
no-slip condition no obeyed?
Views:
5,641
Posted By
ghorrocks
http://www.cfd-online.com/Wiki/Ansys_FAQ#Why_do_I_...
http://www.cfd-online.com/Wiki/Ansys_FAQ#Why_do_I_see_a_non-zero_velocity_at_the_walls.3F
Showing results 1 to 18 of 18
Forum Jump
User Control Panel
Private Messages
Subscriptions
Who's Online
Search Forums
Forums Home
General Forums
Main CFD Forum
System Analysis
Structural Mechanics
Electromagnetics
CFD Freelancers
Hardware
Lounge
Software User Forums
ANSYS
CFX
FLUENT
Fluent Multiphase
Fluent UDF and Scheme Programming
ANSYS Meshing & Geometry
Autodesk Simulation CFD
AVL FIRE
COMSOL
CONVERGE
Fidelity CFD
FloEFD, FloWorks & FloTHERM
FLOW-3D
OpenFOAM
OpenFOAM News & Announcements
OpenFOAM Announcements from ESI-OpenCFD
OpenFOAM Announcements from OpenFOAM Foundation
OpenFOAM Announcements from Other Sources
OpenFOAM Installation
OpenFOAM Meshing & Mesh Conversion
OpenFOAM Pre-Processing
OpenFOAM Running, Solving & CFD
OpenFOAM Post-Processing
OpenFOAM Programming & Development
OpenFOAM Verification & Validation
OpenFOAM Community Contributions
OpenFOAM CC Toolkits for Fluid-Structure Interaction
OpenFOAM Journal
OpenFOAM Bugs
Phoenics
REEF3D
REEF3D News & Announcements
Siemens
STAR-CCM+
STAR-CD
SU2
SU2 News & Announcements
SU2 Installation
SU2 Shape Design
Mesh Generation & Pre-Processing Software
ANSA
enGrid
GridPro
Pointwise & Gridgen
Visualization & Post-Processing Software
EnSight
FieldView
ParaView
Tecplot
Special Topics
Mesh Generation & Pre-Processing
Visualization & Post-Processing
CFD Online Community
Site News & Announcements
Site Help, Feedback & Discussions
CFD-Wiki
All times are GMT -4. The time now is
08:37
.
Contact Us
-
CFD Online
-
Privacy Statement
-
Top
© CFD Online