SOLAR STEAM TABLESThe picnic, which happened to be with friends, will be remembered not only by the abundance of impressions, positive EMOTIONS, but also the uniqueness of what and how food fueled its organizers. After all, improvised marching steam tables this time served… cardboard box from under the computer, pre-laminated on the inside with aluminum foil. And as unconventional source of energy has made itself the southern sun.

Of course, with the examples of concentration and use of helioenergy had the opportunity to meet everyone who in childhood did not catch any winsocki Sunny Bunny and not focused to a point the rays of the midday sun, burning, say, a tree their initials! Rummaging in memory, many will probably be able to recall and more vivid facts. In particular, secondary school curriculum, the end of XVIII century the leading French chemist A. Lavoisier created the first heliopath in which he heated some of the material to a temperature of 1600° C, in 1890, Professor V. Zeratsky carried out in Moscow smelting of metals (at 3000°C and more) the solar energy focused paraboloidal mirror, etc.
But it’s in the distant past, while solving some important cases. And here — the prose of life: heating up food, moreover, in field conditions…
Solar steam tables — sample of practical use of the known from school of law of equal angles of incidence and reflection of light rays. As for the specific variant of the constructive embodiment of a steam tables, winningly simple, undoubtedly, admittedly seen by me at the picnic “hot” box (Fig.1). In fact it is an open cardboard box, reinforced liners-sides and glued from inside with aluminum foil (or a mirror polimernoi film). This coating of the working cavity has a high reflectivity.
Boxed ware, painted in Matt black or just bloated, absorbs sunlight and heats up pretty quickly, thereby increasing the temperature of its contents. This contributes to the greenhouse effect, because heliopath-Bain-Marie is equipped with a transparent cover of two (easier to put in the translation of the structure in the stowed condition) the sheets of plexiglass. Their contribution to the concentration of solar radiation on the dishes bring inclined front wall and cover of the box. Despite the simplicity of such heliostats able in bright southern sun to ensure the temperature of food heating not less than 80…90°C.
However, a more efficient design with a parabolic reflector-concentrator (Fig.2). The mirror may be stacked, is composed of, for example, fitted to each other the pieces of a broken mirror. And as the substrate for laying mosaic mirror will fit perfectly old umbrella or molded by any known methods the sheet of foam (say, from the same computer package).
Fig.1. Hot box:
1 — box (from “mirror” the inner surface), 2 — stand heat, 3 — bowl, heat food, 4 — tab-side panel (with a “mirror” of the inner surface, 2 PCs.), 5 — rock-lock, 6 — lid (plexiglass).
Fig.2. Parabolic reflector-concentrator

Fig.2. Parabolic reflector-concentrator:
1 —”mirror” on the substrate, 2 — insulator (clear container with lid), 3 – a bowl of warm food, 4 — stand heat, 5 prop (material, size, and number).

In the optical focus of the reflector on stands from scrap materials is set outside smoked a bowl of warm food. To minimize the loss of energy as thermal coats for bowls use a spacious pan is made of transparent ceramics or glass recommended for cooking in microwave ovens.
the reflector is adjustable by putting a matching edge stones or any other material at hand.
Of course, you can make a similar heliomare from strong and durable materials. For example, from light aluminum alloys. But it will inevitably entail complication and appreciation of construction. Isn’t it better to search for the optimum to stay on a compromise solution?

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