The purpose of this work was to design a new PCM-shading system and the investigation of its thermal performance. The employed PCMs were tested for their thermal (enthalpy, thermal conductivity, heat capacity) and mechanical properties (volume change, density). Also three system designs and means of encapsulation were investigated. The thermal performance of the PCM shading system was tested with a newly built apparatus in which the sample is irradiated with a metal halide lamp used as solar simulation unit. Measurements on small units (i.e. one slat) of the PCM-shading system have been carried out, to determine the temperature distribution for the different designs and to validate the numerical model. Measurements with the solar simulator and numerical simulations were found to be in good agreement. First measurements of a complete PCM-shading system under real conditions were carried out in a south facing office of the ZAE Bayern in Wuerzburg, Germany. The PCM used in this case was paraffin with a melting point of 24°C. The temperature rise of the shading system upon full solar irradiation could be delayed for 3.2 hours.
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