Over the weekend (06/15 – 06/17 2018) it was time again for the members of SoWaDi to meet for further tests regarding the renewed construction of the plant. In order to accomplish this, our team built up the whole device within two days. The main focus was on bending the aluminium sheets, copper pipe and the glass front of the absorber. In all three cases, extensive changes in implementation and quality have been made in recently which were finally audited for their efficacy.
For the bending of the sheets, the new and oversimplified deep-drawing device was used. This allowed the sheets to be processed faster and much quieter (without hammering).
Also, the newly introduced sand filled copper pipe was used in during the construction to prevent constrictions during bending. The first hurdle was to completely fill the 10-meter pipe with sand and, if possible, without entrapping air inside, unfolding the coil and putting too much strain on the material itself. This was achieved by using a ladder and gently shaking the entire tube. All the effort proved to be worthwhile as the pipe remained completely intact without any constrictions by the time of its implementation. The removal of the sand could also be solved elegantly by rotating the construct like a stirring wheel after connecting the tube to the aluminium sheers.
The innovation of the glass front was to divide the bottom of the glass panes horizontally into several sections. This approach is intended to better distribute the thermal load and to mitigate the risk of the glass cracking via thermal expansion.
In the coming weeks, the system will be tested for its performance. In order to accomplish this the temperature of the water output and the solar radiation will be measured.