Very distorted elements

OldEngineer · March 28, 2020, 12:19

Greetings to all. I need to do a transient simulation on ocean tides involving free surface. The domain is two or three kilometers long and wide and a few meters deep, therefore, its mesh has volumetric elements of approximately 50m*50m*0.01m, that is, highly distorted elements. He made various intentions at CFX. Initially the simulation starts but there is always a numerical error after minutes or hours of calculation. Is it possible to simulate with such distorted elements? If yes, any advice?

Thanks

ghorrocks · March 29, 2020, 00:39

This will be a challenging simulation in CFX. Make sure that you are using a suitable model for the case - turn off unnecessary models (eg surface tension, viscous heating etc), and make sure the elements are as orthogonal as possible. Also double precision will be essential.

Also consider doing this model in a more appropriate software. Have you looked at gerris for this? It has some useful models for this and similar models (eg surface waves).

OldEngineer · March 29, 2020, 04:32

I wil try it again. Thank you very much.

March 28, 2020, 12:19	Very distorted elements	#1
OldEngineer New Member Pedro Dieguez Join Date: Mar 2020 Posts: 4 Rep Power: 6	Greetings to all. I need to do a transient simulation on ocean tides involving free surface. The domain is two or three kilometers long and wide and a few meters deep, therefore, its mesh has volumetric elements of approximately 50m50m0.01m, that is, highly distorted elements. He made various intentions at CFX. Initially the simulation starts but there is always a numerical error after minutes or hours of calculation. Is it possible to simulate with such distorted elements? If yes, any advice? Thanks

March 29, 2020, 00:39		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	This will be a challenging simulation in CFX. Make sure that you are using a suitable model for the case - turn off unnecessary models (eg surface tension, viscous heating etc), and make sure the elements are as orthogonal as possible. Also double precision will be essential. Also consider doing this model in a more appropriate software. Have you looked at gerris for this? It has some useful models for this and similar models (eg surface waves). __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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March 29, 2020, 04:32		#3
OldEngineer New Member Pedro Dieguez Join Date: Mar 2020 Posts: 4 Rep Power: 6	I wil try it again. Thank you very much.