Solar Collector Research Paper

CHAPTER 2 HISTORICAL BACKGROUND

2.1. Solar Energy absorption (solar energy collectors): A solar collector is a device which absorbs solar radiation and converts it into heat. This heat is then used to heat collector fluids like air, water and oil. Solar collectors are designed in such a way that they have high absorption and low emission. Example: The earth is “Solar Collectors”. So the other planets and asteroids in star system. Everything under the sun is a “solar collector” approaching the concept of “solar energy” for this perspective has a liberating effect on the design process Basic Components in solar collectors: Generally, there are two basic elements

More than two-third of the earth’s surface is covered with water. Most of the available water is either present as seawater or icebergs in the Polar Regions. More than 97% of the earth’s water is salty; rest around 2.6% is fresh water, available in rivers, lakes and underground water reservoirs. It has been polluted due to industrial, agriculture and population growth during the current years and now a day’s nearly 1% of earth’s fresh water resources can be used for drinking and agriculture. Nature itself provides most of the required fresh water, through hydrological cycle. Based on the literature surveys, in many parts of the world the 2/3rd humanity will face a shortage of water by 2025. Due to lack of infrastructure and poor quality (brackish/ saline) of available fresh water resources, the Solar distillation of brackish water is a one of the good options to obtain fresh for domestic, hospitals, battery charging and other applications. Solar distillation is an attractive alternative because of its simple technology, non-requirement of highly skilled manpower for maintenance and low energy intensive. It can also be used at any place located at remote area without many

Thus evaporating water which gets condensed on the cooler under side of the glass and gets collected as distillate attached to the glass. Heat and Mass Transfer in Solar Still:

Heat is a form of energy that may be transferred from one body to another if a temperature difference exists. In solar distillation the heat transfer is due to both internal and external losses. Thermal Conduction:

• Conduction is the transfer of thermal energy between particles within a system.

• For conduction, the particles must be in direct contact with one another.

• A temperature gradient must exist.

• The rate at which energy is transferred is dependent on parameters of the system which include its geometry, thickness and the material from which it is made.

Thermal Convection:

• Convection is heat transfer that occurs within a fluid.

• Heat is transferred from one part of the fluid of higher temperature to another part of the fluid at a lower temperature.

• Convection can be both free and