09. Heat and Mass Transfer

Thermally activated wall panels containing a micro-encapsulated phase change material (MPCM) were constructed and tested in the heating mode in the lab environment. Each panel contained 17 U-shaped plastic tubes for liquid heat transfer fluid embedded in the 15 mm thick plaster layer containing MPCM. The phase change temperature of the MPCM was 21 °C. A thermal storage tank was used as a source of constant-temperature heat transfer fluid (water was used as the HTF in the experiments). A PC-based data acquisition system was employed to monitor the experiments. The monitored parameters included the heat flux rate from the panel, panel surface temperatures, surrounding air temperatures, water flow rate, water temperatures, and several other parameters. A thermal imaging system was employed to assess the uniformity of the surface temperature of the wall panel. The present study builds on the previous work of the authors focusing on thermally activated panels with MPCMs. An earlier developed 1D model was created as a type in the TRNSYS simulation tool. A combined heat transfer coefficient was considered in those studies, since the main focus was on the overall heat transfer rates from the panels. The present study addresses radiative and convective heat transfer rates separately as to better address thermal comfort with the model of the wall panels. The experiments were conducted for several temperature differences between the panel surface temperature and the ambient temperature (differences from 6 K to 25 K).

Prof.

Milan Ostrý