Heat Exchanger????

[GoVertical]

Greeting, I am working on a solar tracker and I am considering a stationary heat exchanger to aid in ease of fabrication and to keep cost at a minimum.  I am planning to add a small reflector dish and a magnifying lens to relocate the focal point behind the main parabolic reflector. This would allow for the heat exchanger to be stationary. The shape of the heat exchanger would resemble the appearance of a reversed capital J, that would allow the focal point to always be focus on the heat exchanger as the tracker followed the sun through out the day. What is the best material to use for the heat exchanger fabrication that can be easily obtained.  This is my first attempt at a solar tracker.   Thanks in advance for any help received.

[GoVertical]

Try one more time

[wooferhound]

You don't need the glass lens and it will burn up
http://fieldlines.com/board/index.php/topic,143462.0.html
The second reflector is already a lens
Every reflector or lens has some percentage of loss

The reflector looks OK but the most impressive thing about this design will be the Tracker
Show me the design for the tracker.

[wooferhound]

after looking closer I recognize what you are designing is a Reflector Telescope
See this link to give you a bunch of variations of that design
http://en.wikipedia.org/wiki/Reflector_telescope

[GoVertical]

Greetings, thanks for the link to the reflector telescope. That is where the idea came from.  I would like to have the heat exchanger stationary so I do not have to deal with flexible tubing and keep fabrication cost low.  The proto-type is being constructed using a small TV dish covered with Mylar. By adding the lens I am hoping to increase the output.   I am trying to mill the circuit board using a small CNC router I have. I just finished the G-code for the board. I will post more as the project progresses. Thanks again and best regards.

[wooferhound]

Once again . . .
The reflector is already a lens, you do not need to add a glass lens with it's losses and heat !

[GoVertical]

Greetings, thanks for heads up. It is just a concept drawing.  What is a better thermal mass? Just water or water and stones? What do think about the stationary heat exchanger?

[wooferhound]

According to this heat capacity chart
http://www.diracdelta.co.uk/science/source/s/p/specific%20heat%20capacity/source.html
Water has a heat capacity of 4190, Concrete has a heat capacity of 3350
so water would be better than stones, in fact, water beats out everything else . . .
it will be an interesting design ! !