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understanding dual-time stepping
Hi
I have just started reading about dual time stepping. I want to implement the Weiss and smith preconditioner, with dual time-stepping to maintain temporal accuracy. I have 1 fundamental doubt When the multistage algorithm for the dual time stepping is implemented, how do we know that d/d(tau)(..)=0? I understand how backward difference is used for the physical time term and how the residual is calculated etc. How many stages should there be to ensure convergence of the dual-time stepping? Thanks Srinath |

Re: understanding dual-time stepping
Hi,
you can decide wether d/d(tau)(..)=0 is achieved or not by either 1) monitering residual for each inner loop (that is each intermediate steady state problem) and this residual computation is same as you do for a normal implicit procedure to solve a steady state problem. 2) Or you can say d/d(tau)(..)=0 is achieved just by some experince that it may achieve after N no of iterations (this method helps you to get rid of additional residual computation). Thanks, vinayender. |

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