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Sensitivity Analysis of Melting and Freezing of Snow on Roofs

  • Anker NielsenEmail author
Conference paper
Part of the Springer Proceedings in Energy book series (SPE)

Abstract

The paper describes a statistical analysis of a mathematical model for calculation of the melting and freezing of snow on roofs. Parameters are roof length, overhang length, heat resistance of roof and overhang, outdoor and indoor temperature, snow thickness and thermal conductivity. If the snow thickness is above a limit value, then part of the snow will melt. This gives water flow to the overhang. Part of the water will freeze on the overhang and a part will drip from the roof. If the water flow is small, then all the water will freeze on the overhang otherwise there will be dripping and icicles. The paper uses sensitivity analysis with the Morris method to find parameters that are negligible, linear or non-linear. The Sobol sensitivity indices are also calculated. By means of sensitivity analysis, it is possible to determine, which parameters are the most important e.g. the thickness of the snow or indoor and outdoor temperatures and roof thermal resistance. In practice, some parameters are difficult to change, but the analysis shows where the effect is most efficient.

Keywords

Snow Statistical analysis Roofs 

References

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Building and Process, Danish Building Research InstituteAalborg UniversityCopenhagen SVDenmark

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