Model Based Optimization of an Insulating Panel Made from Biogenic Residues

Within the scope of this article is the development of a mathematical model of an insulating panel made from grain husks and the optimization of the panel regarding the thermal characteristics by using this self-developed thermodynamically model. The model comprises one husk as the smallest unit of the insulating panel. In order to solve the model analytically, the following relevant parameters have been determined:

  • husk geometry
  • density of the pure husk material
  • thermal conductivity of the pure husk material
  • emission coefficient of the husk's surface
  • convection coefficient inside the husks
  • density of the binder
  • thickness of the binder
  • thermal conductivity of the binder

The solved model is validated with produced insulating panels out of grain husks. The optimization of the effective thermal conductivity λeff is done regarding the following parameters:

  • the filling gas
  • the edge length of the husks

According to the results of the simulation, by using Xenon as filling gas instead of air, the effective thermal conductivity λeff can be reduced by 21.6%. The optimal value of the husk’s edge length a depends on the filling gas und therefore varies between 4 and 6 mm. The optimization of the edge length leads to a reduction of the effective thermal conductivity λeff of 7.5 %, according to the model. When implementing individual calculated optimizations in real insulation boards, the thermal conductivity could be improved by up to 32 %. The project is funded by BMWi, the German ministry of economy and energy, and supervised by AiF, the working group of industrial research associations.

Publikationsart
Zeitschriftenbeiträge (peer-reviewed)
Titel
Model Based Optimization of an Insulating Panel Made from Biogenic Residues
Medien
Construction and Building Materials
Heft
2022
Band
Volume 318
Artikelnummer
125807
ISBN
ISSN 0950-0618
Autoren
Prof. Dr. Andreas Ratka , M.Eng. Johanna Hofmann, M. Sc. Wolfgang Ernst
Veröffentlichungsdatum
01.12.2021
Zitation
Ratka, Andreas; Hofmann, Johanna; Ernst, Wolfgang (2021): Model Based Optimization of an Insulating Panel Made from Biogenic Residues. Construction and Building Materials Volume 318, 125807 (2022). DOI: 10.1016/j.conbuildmat.2021.125807