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8 Cards in this Set
- Front
- Back
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What are the four basic components to a solar hot water system
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Collector, storage tank, circulation system, booster unit.
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What are the different types of heat transfer?
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Radiation (electomagnetic radiation - photons)
Convection (eg. fluid) Conduction (electron diffusion or phonon vibrations) Reflection (dispersion) |
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What are the points of heat loss in a solar collector
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Reflection of glass (3-4%)
Reflection of copper plate (3%) Radiation off glass (3%) Radiation off copper |
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What is Newtons law of cooling?
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The rate of heat loss of a body is proportional to the difference in temperatures between the body and its surroundings, or environment.
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What is the purpose of douple glazing a collector and when is it most beneficial?
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double glazing reduced heat loss by convection, conduction and re-radiation. i.e. it reducing the effect of Newtons law of cooling.
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What are some problems with natural thermosiphon?
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The force of natural thermosiphon is not very strong therefor a bend in the pipe that drops below the line of the pipe can cause air bubbles (if in the system) to block at the bend. The tank must be above the collector and not too far away.
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What are the three different configurations of collectors relative to storage tanks?
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Close coupled, thermosiphon system
Remote storage, theremosiphon system Split system or forced circulation systems. |
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How does circulation occur in close coupled thermosihon systems?
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Hot water is less dense than cold water so it rises. The rate of flow is proportional to the rate of solar radiation on the panel.Circulation will occur when there is a temp differential between water in the tank and water in the collector.
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