Solar heater with glass vacuum tubes - has absorber layer between tubes and heat exchanger or inside tubes

摘要

The solar heating system employs evacuated parallel glass tubes (1) internally coated with a heat reflective layer (2) of e.g. In2O3, resting on a heat exchanger layer (3). This may be of extruded aluminium, suitably corrugated to locate the bases of the tubes, and may incorporate water channels (4). The tubes may be secured by adhesive. Triangular channels (7) between the glass tubes and above the aluminium heat exchanger surface can serve as rain channels. The whole is mounted on a layer (6) of insulation material. Between the tubes (1) and the heat exchanger (3) is an absorber layer (5). In an alternative design the absorber layer may be inside the bottom of the tubes (1), the remainder of the inside carrying the reflective layer (2).