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[abdulrahman86]

 
Hi

I am trying to model a solid long building inside a fluid domain, I saw in a previous post an answer from peteroznewman to improve the meshing for such geometries in 

https://forum.ansys.com/forums/topic/reduce-mesh-skewness-for-an-isolated-generic-building/

I tried to create the same concept, but it didn't work well for me as the quality measures are very low in all aspects

My model is a large one and I am trying to have smaller elements around the body and larger ones far away with the small number of mesh as possible to maintain a reasonable solution time. The meshing file is attached and it will be appreciated if someone can check it for me.

Thanks

[Keyur Kanade]

As ANSYS Staff, we can not download attachments. Please insert images using insert image functionality. 

You will have to use different sizing functions. 

Please have a look at 

Also please go through help document on sizing. 

Regards,

Keyur

 

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[abdulrahman86]

 
Thank you for your answer, but I don't think that answers my question. I will post some pictures for my mesh
Currently I am trying two approaches, 1st using surface slice and edge sizing and the other one using the global mesh and face meshing all the faces of the object 

 

The other method I am trying using 

 

Many thanks

[Keyur Kanade]

Please use patch confirming tetrahedron method. 

Please use face sizing. 

Also check body of influence. Define BOI. 

Please check 

https://forum.ansys.com/forums/topic/body-of-influence-for-sizing/

Regards,

Keyur

 

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[abdulrahman86]

Thank you that increased the quality significantly.

For such geometry with fluid domain of 1300  x 750 x 350 m and a building of 30 x 45 x 182 m

what do you suggest for sizing 

I chose Global 30 m, BOI 10 m, face meshing 1 m and got around 1.1 million cells 

is that enough or too low as in the solver I am getting the turbulent viscosity limit issue of 200K cells 

 

[Rob]

It depends, are you resolving the flow gradients?

[abdulrahman86]

I am not quite sure about the meaning of flow gradients. however, I am interested in the pressure on the surfaces due to the wind and the drag coefficient for validation