Simulation, testing and design of a fully adhesive bonded flat plate solar collector for highly automated production

This thesis presents simulation results and experimental data for a collector type with an all-round supported absorber and a fully adhesive edge bond that is produced on a highly automated production line. A literature review discussing measures to reduce the convective heat loss in flat plate collectors as well as on the status quo of the collector production was conducted. It was determined that an adaption of an existing automated production technique from the insulated glazing industry opens new paths towards a collector design allowing a mass production and an improved thermal collector efficiency. Within the thesis, the thermal and mechanical behaviour as well as the applied production method for this collector type are discussed. By implementing and validating a finite element model of the collector, the absorber deflection was analysed, different calculation approaches compared and conclusions drawn on the pressure change in the cavity of gas-filled collectors. Unlike stated in the literature, it was found that the thermal elongation of an all-round supported absorber has a considerable effect on the overall collector performance. Based on these conclusions, an optimised sheet-pipe absorber structure is introduced allowing a predictable absorber deflection and, thus, reduced chance of contact between absorber and glazing in collectors. The findings of the thermal simulation and, in particular, on the convective heat transfer confirmed the reliability of a recently extended convection calculation approach for solar collectors. Even though the gas-filled collector is capable of a superior thermal performance, simulation and testing results could not confirm the calculated efficiency increase given in recent literature. In comprehensive testing, the strengths and weaknesses of different batches of prototypes are discussed. Based on an economic analysis considering the collector production costs and the solar yield, the new approach was compared to a conventional solar collector.

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

2017

Author dc:creator

• Riess, Hermann

Licence

• https://dora.dmu.ac.uk/bitstreams/eaa2a3ad-e5c9-45a9-b6bf-b943e31b1e5a/download