Package porosity layers

Figure 6.36 illustrates the influence of porosity change across the package layers on dye transfer behaviour. Dotted and dashed curves represent the CDEP when the package porosity linearly decreases from 0.5 to 0.462, and increases from 0.5 to 0.538 (or the package density increases and decreases) with distance... 

To simplify the model, researchers in this field usually consider the yam to be uniformly wound throughout the package, and thus constant porosity is assumed in these mass transfer models. In practice, however, the yam may be wound tightly at the iimer layers and more loosely at the outer layers of the package, or vice versa. Current analysis assumes that the porosity is a function of the distance, i.e. ... 

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