Dimension-Dependent Long-Term Aging of Cellular Plastic Insulations

Abstract

The commercially available closed-cell cellular plastic insulations are typically faced by gaseous impermeable metal foil to prevent transfer of gases from inside and from outside of the foam. Thus, the long-term aging properties of the foams will be different from the unfaced situation. In this research, it has been found by experiments and simulations that the long-term thermal conductivity of the faced foam will follow a simple logarithm correlation.

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Where AX is the thermal conductivity increase of the foam after some years later (say 25 years); P is the perimeter of the unfaced surfaces of the foam; A is the unfaced surface areas of the foam; α_o and α₁, are determined constants. In addition, this research will give this correlation with respect to the CFC-11 and n-pentane based cellular plastic insulations (CPI) under different facing conditions.

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References

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