DG method, very small time step

Wenjun · April 17, 2013, 06:34

When I apply the Discontinous Galerkin method on the KdV equation, the time step can only take very small number, like 0.0001. Can anyone tell me it is normal or not. Thanks !

cfdnewbie · April 17, 2013, 06:38

Quote:

Originally Posted by Wenjun

When I apply the Discontinous Galerkin method on the KdV equation, the time step can only take very small number, like 0.0001. Can anyone tell me it is normal or not. Thanks !

yeah, DG has a timestep of 1/(2n+1), where n is the ansatz degree. Which order is your ansatz?

Wenjun · April 17, 2013, 06:43

Quote:

Originally Posted by cfdnewbie

yeah, DG has a timestep of 1/(2n+1), where n is the ansatz degree. Which order is your ansatz?

I am a new guy of DG. I use the second-order element and the third-order TVD Runge-Kutta method. I set dx = 0.1, how should I choose the time step?

April 17, 2013, 06:34	DG method, very small time step	#1
Wenjun New Member Join Date: Mar 2013 Posts: 14 Rep Power: 14	When I apply the Discontinous Galerkin method on the KdV equation, the time step can only take very small number, like 0.0001. Can anyone tell me it is normal or not. Thanks !

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Multiple floating objects	CKH	OpenFOAM Running, Solving & CFD	14	February 20, 2019 10:08
InterFoam negative alpha	karasa03	OpenFOAM	7	December 12, 2013 04:41
mixerVesselAMI2D's mass is not balancing	sharonyue	OpenFOAM Running, Solving & CFD	6	June 10, 2013 10:34
pisoFoam with k-epsilon turb blows up - Some questions	Heroic	OpenFOAM Running, Solving & CFD	26	December 17, 2012 04:34
Upgraded from Karmic Koala 9.10 to Lucid Lynx10.04.3	bookie56	OpenFOAM Installation	8	August 13, 2011 05:03