SELEKTIVE ABSORPTIONSOBERFLAECHE EINES SONNENENERGIE-SAMMLERS UND VERFAHREN ZU DEREN HERSTELLUNG

摘要

The solar collector selective absorption surface comprises a substrate coated with a layer of metal oxide of thickness between 500 and 2,000 angströms. It may be prepared by soaking a sheet of stainless steel polished like a mirror in an acidic or basic bath. The absorption coefficient ( alpha ), the emission coefficient ( epsilon ) and the efficiency ( eta ) of the selective absorption surface are represented as a function of the roughness Ra.