Test method for the determination of the long-term stability of absorber welding seams in flat plate solar thermal collectors

摘要

Within the framework of the SpeedColl2 ("Service life estimation for solar thermal collectors and their components") project a rapid test method for the alternating thermal load of flat plate solar thermal collectors is being developed. The development of the test procedure is described based on annular solar thermal system simulations for different locations and cases of application. The test procedure consists of thermal performance tests at the beginning and end of the procedure and the appliance of alternating thermal loads on the flat plate solar thermal collector in between. The test procedure was applied using two different flat plate solar thermal collectors. The test results show very different results for both collectors, thus more collector tests have to be performed in order to gather more reliable results. The results include thermal performance tests as well as further investigation of the welding seams between the absorber and absorber pipes.