Concrete Block

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eordner
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Concrete Block

Post by eordner » Wed Jul 23, 2008 11:06 am -1100

What is the proper way to model CMU? Should I model the face shells and cells? Or should I use the "concrete brick" material for the 8 inch width of the unit. In other words, does the "concrete brick" material data account for the cells too?

Thomas
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Re: Concrete Block

Post by Thomas » Fri Jul 25, 2008 4:01 am -1100

Hi eordner,

it usually does not make much sense to try and model the two- or three-dimensional structure of a material in a one-dimensional simulation tool. We usually treat such materials (e.g. hollow bricks etc.) as a homogeneous material, with 'effective' material properties if needed.

Unfortunately I do not know whether the material data for the concrete brick already include the effect of the hollow spaces or not. The thermal conductivity suggests that yes, the bulk density suggests that no. I'll try to alert Dr. Karagiozis form ORNL to this question, he should be familiar with the source that was used for these data.

Regards,
Thomas

Foti
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Re: Concrete Block

Post by Foti » Wed Sep 28, 2022 3:33 pm -1100

Hello Thomas,

I know the initial post is very old, I jumped from the free version to the pro and I would need this info as well for a baseline simulation I have to perform. Has there been any updates on this?

Christian Bludau
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Re: Concrete Block

Post by Christian Bludau » Fri Oct 14, 2022 12:50 am -1100

Hi Foti,
for a one dimensional simulation best way is to use effective values for the whole brick.
Have a look on the "Concrete Blocks, pumice aggregate" from the Fraunhofer IBP database. Based on that you can try to set up a new material. For typical aggregates the density will be higher as the thermal conductivity may be changed. The vapor diffusion resistance will probably remain in this low range.
Christian

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