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fluid solid interaction for blood flow

Posted 15 gen 2014, 16:28 GMT-5 Version 4.2a 3 Replies

Kamil Kahveci
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Hi, I am trying to model blood flow in a cylindrical elastic blood vessel. I am using velocity inlet and pressure outlet boundary conditions. The program does not converge. According to my search, i need to use special solver settings. I have tried many things in the last two weeks without success. Program finds solution for the rigid case. But for the elastic case, I cannot succeed convergence.
3 Replies Last Post 16 gen 2014, 10:29 GMT-5
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago 15 gen 2014, 16:55 GMT-5
Hi Kamil,

Try using the Fully Coupled Solver instead of the Segregated Solver. It sometimes works better when the structure is soft. Also, try ramping up the inlet velocity from zero to its desired value. That should help with convergence.

Nagi Elabbasi
Veryst Engineering
Hi Kamil, Try using the Fully Coupled Solver instead of the Segregated Solver. It sometimes works better when the structure is soft. Also, try ramping up the inlet velocity from zero to its desired value. That should help with convergence. Nagi Elabbasi Veryst Engineering
Kamil Kahveci
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Posted: 1 decade ago 15 gen 2014, 17:52 GMT-5
Thank you very much Mr. Nagi for fast reply. Bu t I do not know how to ramp up the velocity. Could you inform me about that. Thanks in advance.
Thank you very much Mr. Nagi for fast reply. Bu t I do not know how to ramp up the velocity. Could you inform me about that. Thanks in advance.
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago 16 gen 2014, 10:29 GMT-5
If it’s a stationary analysis you can do that by multiplying the inlet velocity with a new parameter that increases gradually from zero to one using Parametric Sweep (see documentation for details). If it’s a transient analysis you can multiply the inlet velocity with a step function that increases gradually from zero to one.

Nagi Elabbasi
Veryst Engineering
If it’s a stationary analysis you can do that by multiplying the inlet velocity with a new parameter that increases gradually from zero to one using Parametric Sweep (see documentation for details). If it’s a transient analysis you can multiply the inlet velocity with a step function that increases gradually from zero to one. Nagi Elabbasi Veryst Engineering

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