CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

time step!!!

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

LinkBack Thread Tools Display Modes
Old   February 2, 2010, 12:09
Default time step!!!
New Member
Vijesh Joshi
Join Date: Mar 2009
Posts: 10
Rep Power: 8
vijeshjoshi23 is on a distinguished road
Hello friends,

I am solving 1-d transient heat conduction equation by FVM. I am trying to analyze "heat flow through a very thin sheet of steel". Sheet thickness is 0.5mm. q on one side is given AND IS VERYING WITH TIME. Becoz of higher K (43 W/m-K) value of steel, I am in need to use very small time step. I used dy=0.5mm/3=0.167mm=1.67e-4 m.. dt=0.01sec ... But results are not converged.. I am using fully implicit scheme to solve the transient cond eq... Do I need to worry abt Courant number?? Is there any other way that I can solve this problem with higher time step???
vijeshjoshi23 is offline   Reply With Quote

Old   February 2, 2010, 23:22
Senior Member
Julien de Charentenay
Join Date: Jun 2009
Location: Australia
Posts: 229
Rep Power: 9
julien.decharentenay is on a distinguished road
Send a message via Skype™ to julien.decharentenay

Can you clarify what do you mean by q (which I take as a heat flux at one end) is "VERYING WITH TIME"?

I understand the need for very small time-step as the plate is both thin and has a high thermal diffusivity. But considering that you are using an implicit integration scheme (and we are talking about diffusion only), I would think that the time-step should relate to the time variation of "q". The courant number is a limitation related to the convection term (Co = Dt * U/ Delta) and is not relevant to a diffusion only problem.

julien.decharentenay is offline   Reply With Quote


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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 18 March 3, 2015 06:36
DPM particle time step amos FLUENT 0 December 1, 2009 04:31
HELP! time step too small? meangreen Main CFD Forum 5 August 27, 2009 12:32
Overflow problem in steady simulation ReeKo CFX 11 October 8, 2008 17:57
A Problem with setting the time step in VOF model Le FLUENT 2 July 20, 2006 22:00

All times are GMT -4. The time now is 16:18.