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HAMT: how does it split surfaces into cells?

asked 2018-08-21 21:21:38 -0500

rtsuchiya's avatar

updated 2018-08-22 00:02:02 -0500


I am now trying to apply HAMT in my project. In that, there is a thing I cannot understand.

When checking Engineering Reference, it says

"“Surfaces” are made of a number of layers of potentially any combination of materials. Each surface is split into its constituent materials and is then split up further into cells through its depth."

Here, how does the program split a surface into cells?

Automatically, or are there any ways to define coordinates of cells by users?

In addition, my target has an earth floor.

In this case, what kind of the outside boundary of RH is used if I apply HAMT to the floor; always 0 ? (I understand this method is not suitable for vertical water movement underground which is driven by gravity. But I want to know this.)

I would appreciate for any kinds of information from you...

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2 Answers

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answered 2022-04-19 12:28:15 -0500

The elements subdivision is reported in the ".eio" file

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Thank you for the information.

rtsuchiya's avatar rtsuchiya  ( 2022-04-19 18:47:21 -0500 )edit

answered 2018-08-22 10:06:05 -0500

updated 2018-08-22 10:07:03 -0500

In the Internal Cell Outputs documentation it states:

HAMT automatically assigns cells to construction objects so that there are more cells closer to boundaries between materials and also at the “surfaces” of the surface. It is not possible for users to define their own cells.

Digging into the source code, it appears that after the number of cells are determined (based on material thickness and conductivity) the cell thicknesses are determined by the equation here.

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Thank you for your information. I didn't check the output part.

How about the second question? If HAMT is applied to floor, in that case, still external RH is used for outside boundary?

rtsuchiya's avatar rtsuchiya  ( 2018-08-22 21:14:46 -0500 )edit

From the Engineering Reference:

Surfaces with Ground exterior boundary condition assumes saturated air (100% relative humidity) condition to calculate the exterior mass transfer coefficient, which is used to model mass transport through a ground contact surfaces.

ericringold's avatar ericringold  ( 2018-08-23 08:44:11 -0500 )edit

I see. Thank you very much for the information.

rtsuchiya's avatar rtsuchiya  ( 2018-08-23 20:01:27 -0500 )edit

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Asked: 2018-08-21 21:21:38 -0500

Seen: 251 times

Last updated: Apr 19 '22