time step

August 30, 2005, 11:48

Hi,there

For steady state problem, it usually need to give a large time step at beginning and then gradually reduce that.

How about the time step for transient problems? Should I give a large or small number to start the solver?

Can someone share your experience?

Regards!

Rob

August 31, 2005, 18:11

Hi,

If the problem is stiff, then it is generally recommended that you start with a small time step, due to its instability issues at the start. But as the simulation progress, you could potentially increase the time step.

RK

August 31, 2005, 20:08

Thanks Robin.

August 30, 2005, 11:48	time step	#1
Rob Guest Posts: n/a	Hi,there For steady state problem, it usually need to give a large time step at beginning and then gradually reduce that. How about the time step for transient problems? Should I give a large or small number to start the solver? Can someone share your experience? Regards! Rob

August 31, 2005, 18:11	Re: time step	#2
Robin K Guest Posts: n/a	Hi, If the problem is stiff, then it is generally recommended that you start with a small time step, due to its instability issues at the start. But as the simulation progress, you could potentially increase the time step. RK

August 31, 2005, 20:08	Re: time step	#3
Rob Guest Posts: n/a	Thanks Robin.

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