Wood boards ¼ inch thick have a moisture content of 60% by mass. If the diffusivity of water in wood is taken as 3 x 10^-10ft^2/s, estimate the time for the wood to have a moisture content of 5% at its center if the air surrounding the boards was originally dry and hD (the convective mass transfer coefficient) is 1 x 10^-8ft/s.
What will be an ideal response?
If the boards are very large, the use an infinite plate can be used to model this problem.
The use of Equation 3-29, modified for mass transfer, may be used.
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