the element size must be greater than .....

Altair Forum User

I am new in using HM. In my research I use hm to mesh the object into finer triangular grids, even seveal millions of grids! But when I set the element size in the 2d auto mesh, the information was that the element size must be greater than ... for example 0.0023333. Note that not 'must be greater than the node tolerance'. I have already set the node tolerance smaller than the element size.

what should I do next? Thank you! 

Altair Forum User

Hi,

 

i have found the following restrictions:

 

1. the node tolerance must be > then cleanup tolerance/100

2. element size must be > then node tolerance

 

Set cleanup tolerance to e.g. 1e-7

Set node tolerance e.g. 1e-7

Set element size to e.g. 5e-5

 

Maybe there is a internal limit. At all it is better not to work with that small values, instead change the unit system

 

Regards,

Mario

Altair Forum User

For all 'aero' works (in MM), we use often cleanup = 0.02~0.05 and node tolerance = 0.02~0.05.

For CFD works, we use smaller values.