Stationary Solar Collector
From Swikipedia
Introduction
A Stationary Solar Collector is the one that does not use any mechanisms to track the sun. They can produce heat at low and medium temperatures (up to 150 °C). Flat-plate collectors, evacuated tube collectors and CPC type concentrators, belong to this group of collectors.
Brief Description
The stationary solar heat collector includes a reflector having a substantially upwardly facing concave reflective surface and an absorber tube supported relative to the reflective surface for receiving reflected sun rays there from. The reflective surface is defined in cross-section by first, second and third semi-parabolic curves arranged in generally end-to-end relation. The surface may have a shape generated by moving the curves along a line perpendicular to the plane of the curve or by rotating the curves about the free end of the first curve.
The equations, lengths and orientation of the three curves relative to one another have been selected to maximize the acceptance angle of the collector for operation during a majority of the daylight hours, and further to maximize the average daily concentration factor for a maximum BTU output for a given size collector. Finally, the combined semi-parabolic curves of the reflective surface cooperate so that accepted sunrays are never reflected more than twice before striking the absorber tube.
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