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Title: Improvements to water vapor transmission and capillary absorption measurements in porous materials

Source: Journal of Testing and Evaluation. 44(6): 2396-2402

Author(s)Zelinka, Samuel L.; Glass, Samuel V.; Boardman, Charles R.

Publication Year: 2016  View PDF »

Category: Journal Articles
Associated Research Project(s):   FPL-4716-1A

Abstract: The vapor permeability (or equivalently the vapor diffusion resistance factor) and the capillary absorption coefficient are frequently used as inputs to hygrothermal or heat, air, and moisture (HAM) models. However, it has been well documented that the methods used to determine these properties are sensitive to the operator, and wide variations in the properties have been reported in round-robin testing. This paper presented an investigation into how these errors can be minimized for porous materials by different edge sealing and also looked at whether automating these techniques can reduce operator artifacts. To automate the measurements, specimens were attached to a balance or load cell and then required no further interactions, which allows massive amounts of data to be collected. The extra data is advantageous for the beginning of the capillary absorption test where the moisture uptake is rapid. Most of the potential for errors in the vapor diffusion tests resulted from uncertainties in how the sample was sealed between the chambers and determining when the steady state region was reached, neither of which can be improved by automation.

Keywords: Vapor diffusion; capillary absorption; wood-moisture relations; hygrothermal modeling

Publication Review Process: Formally Refereed

File size: 616 kb(s)

Date posted: 09/22/2017

This publication is also viewable on Treesearch:  view
RITS Product ID: 86891
Current FPL Scientists associated with this product (listed alphabetically)
Glass, Samuel V.
Research Physical Scientist
Zelinka, Samuel L.
Materials Research Engineer

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