implicit / explicit solvers

jk75 · May 27, 2010, 04:20

Hi all,

is there a rule of thumb to determine witch solver (implicit or explicit) is suited better for a given problem?

Regards,
Johannes

jk75 · May 27, 2010, 08:15

http://www.flow3d.com/cfd-101/cfd-10...t-schemes.html

ignatz · May 29, 2010, 03:35

I think the default (explicit) is preferred/recommended for reasons of accuracy.

hamidciv · March 4, 2017, 10:18

Hi Dear friends;

whether using implicit solvers for viscous stress & free surface pressure & advection could be good idea to calculate the sediment scour phonomena in order to reduce the computational time Or it's not recommended?

i appreciate for any comment that could be useful for me.

best regards
hamid

bfox48 · March 6, 2017, 11:04

In the text output in the simulation manager tab, you can get information from the stability code on what is limiting the timestep. Look up the meaning of each code in the user manual. Once you determine which model is limiting the timestep, you can then change this to implicit to try and speed up the simulation.

hamidciv · March 10, 2017, 14:32

Dear Brian, thanks for your response.

with the best wishes for you
hamid

May 27, 2010, 04:20	implicit / explicit solvers	#1
jk75 New Member Johannes Köpf Join Date: May 2009 Location: Germany Posts: 29 Rep Power: 16	Hi all, is there a rule of thumb to determine witch solver (implicit or explicit) is suited better for a given problem? Regards, Johannes

May 27, 2010, 08:15	solved	#2
jk75 New Member Johannes Köpf Join Date: May 2009 Location: Germany Posts: 29 Rep Power: 16	http://www.flow3d.com/cfd-101/cfd-10...t-schemes.html

March 6, 2017, 11:04		#5
bfox48 New Member brian Join Date: Apr 2012 Posts: 25 Blog Entries: 1 Rep Power: 14	In the text output in the simulation manager tab, you can get information from the stability code on what is limiting the timestep. Look up the meaning of each code in the user manual. Once you determine which model is limiting the timestep, you can then change this to implicit to try and speed up the simulation. hamidciv and thunde47 like this.

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May 29, 2010, 03:35		#3
ignatz Member Join Date: Jan 2010 Posts: 39 Rep Power: 16	I think the default (explicit) is preferred/recommended for reasons of accuracy.

March 4, 2017, 10:18		#4
hamidciv Senior Member Hydreaulic structures Join Date: Sep 2012 Posts: 283 Rep Power: 14	Hi Dear friends; whether using implicit solvers for viscous stress & free surface pressure & advection could be good idea to calculate the sediment scour phonomena in order to reduce the computational time Or it's not recommended? i appreciate for any comment that could be useful for me. best regards hamid

March 10, 2017, 14:32		#6
hamidciv Senior Member Hydreaulic structures Join Date: Sep 2012 Posts: 283 Rep Power: 14	Dear Brian, thanks for your response. with the best wishes for you hamid