Mis Trabajos

A greenhouse (or hothouse) is intended for crop production, with a usually translucent outer shell of glass or plastic, which allows control of temperature, humidity and other environmental factorsto promote plant growth. In the old Spanish garden, the greenhouse is called cold stove.
Take the effect of solar radiation from the sun which, passing through a glass or other translucent material,heating the objects inside; these, in turn, emits infrared radiation with a wavelength greater than the solar therefore can not pass through the glass on his return being trapped and causing warming.Emissions from the sun to the earth are on shortwave land while abroad are long wave. Visible radiation can penetrate the glass while a portion of the infrared can not do.
The glass or plastic usedfor a greenhouse works as a selective medium of transmission for different spectral frequencies and their effect is to trap energy within the greenhouse, which heats the indoor environment. Also servesto prevent loss of heat by convection. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature drops considerably. This principle is the basis of automaticcooling system autoventilación.En absence of a coating, the heat absorbed is eliminated by convective currents and by the emission of infrared radiation (wavelength than the visible). The presence ofcrystals or plastics prevents the transport of heat accumulated by convection towards the outside and blocks the exit of a part of infrared radiation. The net effect is the accumulation of heat andincreasing the temperature of the enclosure. View solar greenhouse (technical) for a more detailed discussion of technique solar greenhouse works.
The glasses have very little resistance to the passageof heat transfer (in fact, for single glazing, the heat transfer coefficient is null and only takes into account the amount of surface resistance), so that, contrary to some believe, to have two...