Switchable thermal insulation: results of computer simulations for optimisation in building applications
Ronny Horn, René Neusinger, Michael Meister, Jörg Hetfleisch, Roland Caps, Jochen Fricke
Computer simulations of switchable thermal insulation (STI) for solar heating of building façades have been performed. This technique uses a metal hydride to change the H2 gas pressure within an evacuable panel and thus the thermal conductivity by about a factor of 50. Calculations of heat fluxes and temperatures have been performed in order to find the most suitable system arrangement and control strategy for the utilisation of solar thermal energy. Parameters of the dynamical simulation were the distance between the glass pane cover and the absorber surface, the panel – wall distance, and the dynamics of the switching process. The simulation shows that the annual heat gain can be as high as 140 kWh m-2, with a variation of -30 kWh m-2 upon change of the above parameters.