x-material, y-material?

[yang]

Hello,

I just realise there are x-material and y-material for material assignment. Is that an advanced option for material assignmet? Or I just have to keep the two materials the same.

Thank you for helping.

Yang

[veitner]

That depends on your construction and materials.
The transport coefficients for wooden materials will be different in radial/longitudinal direction e.g.
WUFI2D overtakes density/porosity/heat capacity/moisture storage function from the defined x-material.

Veit

[yang]

Thank you, Veit,

But I am still a little bit confused. Do you mean, the y-material is not important, mostly the x-material is enough?

yang

[avp081090]

Hello yang

Properties in the x-direction is not more important than in y-direction and vice versa. You can set different properties in the two directions because not all materials have same abilities in all directions.

When it has same abilities in all directions it´s called Isotropic material
When it has different abilities in different directions it´s called anisotropic material

ex. mineralwool don´t have the same thermal conduction in x and y direction due to orientations of the fibers.

best regards

[veitner]

Some materials show anisotropy for heat conduction, vapour diffusion and liquid transport at least.
More about in our WUFI2D-workshops

[yang]

Thank you, Veitner, avp081090,

I got it.

If i set mineral wool for x-deirection and EPS for y-direction, then the material would have mineral wool's property in x-direction and EPS' property in y-direction. Am I right?

However, in practice, it is not possible to have mineral wool in x-direction and EPS in y-direction. Should I just keep the two directions the same?

yang

[Christian Bludau]

Yes, that makes no sense to use mineral wool in one direction and EPS in the other, but you got it.

If you don´t have any information (measured values) about the anisotropic behavior of a material use same properties in both directions.

Christian