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Welford, W. T.

Publications and source records attributed to Welford, W. T..

Two-Stage Off-Axis Cylindrical Solar Concentrator

Concentrator uses off-axis geometry to achieve efficient uniform illumination of photovoltaic cells. Primary reflector is parabolic cylinder and therefore readily adaptable to rolling up for transport and unrolling for deployment. Foldable cylindrical structure has potiential for both terrestrial and space applications.

Winston, R.↗

Design of nonimaging concentrators as second stages in tandem with image-forming first-stage concentrators

The paper discusses the paraboloidal mirror as a tracking solar concentrator, fitting a nonimaging second stage to the paraboloidal mirror, other image-forming systems as first stages, and tracking systems in two-dimensional geometry. Because of inherent aberrations, the paraboloidal mirror cannot achieve the thermodynamic limit. It is shown how paraboloidal mirrors of short focal ratio and similar systems can have their flux concentration enhanced to near the thermodynamic limit by the addition of nonimaging compound elliptical concentrators.

Winston, R.↗