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last time step did not converge when deleting the outlet or outflow in physical fields

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I am simulating the process of ice melting. I used the physical fields of laminar two-phase flow(phase field) and heat transfer in fluids. First time the computation gave a reasonable result with the outlet boundary added. But then I thought no ice or water came out in the process. So I deleted the outlet boundary and then an error appeared: last time step did not converge. Has anyone ever seen this problem?ps: after I adjusted the model and added the gravity, the results seemed very irrational——the ice decreased at first and then increased greatly.



1 Reply Last Post Sep 21, 2017, 1:32 p.m. EDT

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Posted: 7 years ago Sep 21, 2017, 1:32 p.m. EDT

Hello ,

I think this problm occurs if your time step is too large. Try decreasing the time step by an order of magnitude and it should work. Also, try constant step size (instead of logarithmic).

Hope that helps.

Vaidehi

Hello , I think this problm occurs if your time step is too large. Try decreasing the time step by an order of magnitude and it should work. Also, try constant step size (instead of logarithmic). Hope that helps. Vaidehi

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