16-08-2014, 03:47 PM
Rotating solar collectors are a new type of solar collector. The boiler consists of two concentric tubes. The inner tube absorbs sunlight and boils water. Thi stube is called the absorber. The outer transparent tube is filled with air and called the cover. The cover is made from transparent plastic. The empty space created between the absorber and cover is called the air layer. The end caps are used to support the cover and insulate the absorber tube. The motor is used to rotate the boiler and the reflexors are used to maximize the sun rays incident on the absorber.
Rotating solar collectors are a new type of solar collector. The boiler consists of two concentric tubes. The inner tube absorbs sunlight and boils water. Thi stube is called the absorber. The outer transparent tube is filled with air and called the cover.
The cover is made from transparent plastic. The empty space created between the absorber and cover is called the air layer.
The end caps are used to support the cover and insulate the absorber tube. The motor is used to rotate the boiler and the reflexors are used to maximize the sun rays incident on the absorber.
The air between the cover and the absorber rotates with the same rotational speed as the cover and the absorber. This causes a centrifugal acceleration to act on the air layer. The effect prevents convection completely when the centrifugal acceleration is greater than the gravitational acceleration. The operation temperature (100 o C) could not be established without the reflectors.
Several important conclusions can be drawn from the experiments
1. Rotation prevents convection in the air layer.
2. The electrical power consumption is not prohibative.
3. Overall efficiency is around 46%.
4. The boiler has enough potential to justify further investigation.
Economical analyses were performed as well. These analyses showed that any solar boiler should be very lightweight in order to reduce material cost. The rotating solar boiler can be lighter and cheaper than convectional flat plate collectors and evacuated tue collectors