A one-dimensional, time transient, heat transport model is developed using the heat equation to solve for the internal temperature distribution with heating from both boundaries. The model includes the effects of moisture on heat transfer within a homogeneous porous medium, in this case paper. The effects of phase change, conduction, and vapor transport are included. With the input of system properties - initial paper temperature, ambient relative humidity (RH), and temperature boundary conditions - the model computes the spatial distribution of temperature, saturation and vapor pressure, and liquid and vapor moisture content. By matching temperature curves for various conditions of relative humidity using a trial and error method, results showed that the effective thermal conductivity increased over the base dry value with increasing relative humidity. In the symmetric case the conductivity increased as much as 2.4X under initial conditions of 80% RH. Similar modeling runs with asymmetric temperature boundary conditions yielded an effective thermal conductivity increase of 3. IX for the 80% RH case.
Library of Congress Subject Headings
Porous materials--Thermal properties--Simulation methods; Heat--Transmission--Simulation methods; Thermodynamics--Experiments; Thermodynamics--Simulation methods
Department, Program, or Center
Mechanical Engineering (KGCOE)
Thomas, Kim, "Simulation of simultaneous heat and moisture transfer in a porous media with heated boundries" (1994). Thesis. Rochester Institute of Technology. Accessed from
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