| Webster's Online Dictionary |
| Expressions | Domain | Definition | |
| Evacuated-Tube collector | Energy | 1: A collector in which solar thermal heat is captured by use of a collector fluid that flows through an absorber tube contained inside an evacuated glass tube. (references) | |
| 2: A collector is the mechanism in which fluid (water or diluted antifreeze, for example) is heated by the sun in a solar hot water system. Evacuated-tube collectors are made up of rows of parallel, transparent glass tubes. Each tube consists of a glass outer tube and an inner tube, or absorber. The absorber is covered with a selective coating that absorbs solar energy well but inhibits radiative heat loss. The air is withdrawn ("evacuated") from the space between the tubes to form a vacuum, which eliminates conductive and convective heat loss. Evacuated-tube collectors are used for active solar hot water systems. (references) | |||
| Evacuated-Tube collector | Geography | Black coated tubular metal absorbers (or sometimes just a strip of flat plate) are mounted in a series of evacuated glass tubes connected in parallel. Behind the tubes is placed a reflecting surface from which the light that passes between the tubes is directed back onto the tubes thus affording an aperture of 360 degrees. This type of collector attains considerably higher temperatures (190-240 F) than flat plate collectors. Source: European Union. (references) | |
Source: compiled by the editor from various references; see credits. | Top | ||
