PREDICTION OF DEGRADATION OF POLYMER TUBES USED IN SOLAR DOMESTIC HOT WATER COMPONENTS

摘要

For polyolefin tubes exposed to chlorinated hot water, lifetime is estimated by a model of the depletion of antioxidant through diffusion and reaction with chlorine ions. A case study for typical tube geometries used in solar hot water applications at 50°C is presented. Characteristic time scales demonstrate that the dominant mechanism for antioxidant depletion is the reaction with chlorine ions that diffuse into the polymer tube.