Timeline for max speed <--> time discretization
Current License: CC BY-SA 3.0
14 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 4, 2013 at 15:52 | history | tweeted | twitter.com/#!/StackSciComp/status/397390829847060480 | ||
| Oct 24, 2013 at 15:11 | comment | added | Jan | Then you maybe should rephrase your question and ask 'What is a suitable analogon to wave speed for heat diffusion in comparison with hydro eqns?' | |
| Oct 24, 2013 at 15:01 | comment | added | Kyle Kanos | @Jan: That's what I'm asking | |
| Oct 24, 2013 at 14:23 | comment | added | Jan | Then you have to define, what is the wavespeed of your PDE. | |
| Oct 24, 2013 at 14:21 | comment | added | Kyle Kanos | @Jan: I am adding this to a hydro code based on another hydro code. Their version uses explicit method and computes $dt$ based on the $dt$ I gave in the Q. My code computes $dt$ based on hydro wavespeeds, I need to compare the wavespeed of the PDE to the hydro wavespeeds. | |
| Oct 24, 2013 at 14:09 | comment | added | Jan | What do you want to have? There is no wave speed of a heat diffusion, see @WolfgangBangerth's answer. Or are you simply about stability of your numerical scheme?? | |
| Oct 24, 2013 at 13:30 | comment | added | Kyle Kanos | @Jan: That makes sense. Now the question is how do I calculate the characteristic speed of this PDE? | |
| Oct 24, 2013 at 13:21 | comment | added | Jan | Since $dt$ and $dx$ is your personal choice, I doubt that you can use them to get a characteristic of the actual continuous equation. | |
| Oct 24, 2013 at 13:09 | comment | added | Kyle Kanos | @Jan: This time step was computed in Reale 1995. I admit I removed a factor of order unity, but that's the essence of $dt$ for this problem. All I am asking is if it's valid to use $dx/dt$ to get the wavespeed, or do I have to do something different. | |
| Oct 24, 2013 at 11:55 | answer | added | Wolfgang Bangerth | timeline score: 2 | |
| Oct 24, 2013 at 8:08 | comment | added | Jan | What do you mean by 'the time step becomes'? I suspect you interprete the CFL condition in the wrong way... | |
| Oct 24, 2013 at 2:14 | comment | added | Kyle Kanos | Density. This is being attached to a hydro code | |
| Oct 23, 2013 at 23:00 | comment | added | Geoff Oxberry | What is $\rho$ here? | |
| Oct 23, 2013 at 13:29 | history | asked | Kyle Kanos | CC BY-SA 3.0 |