Science Buddies: "Ask an Expert"

i need help to fird some heat absorbing matirials........

Hi solar power898,
We are here to help you with your science fair project. Would you please give us some more detail about your science fair project? What are you going to use heat absorbing materials for? It is easier to let us know about your project information. Thank you.

im going to use it for solar oven to compair it to Aluminum for absorbing heat and cookin better.

also raizin the tempiture

solar power898 wrote:also raizin the tempiture

I think you need to re-read your materials on solar ovens. Aluminum doesn't absorb the heat, it reflects it on to the cooking surface. If you put in a lot of materials that absorb heat, then you are not using that energy to cook with.

See for example,
http://www.exoticblades.com/tamara/sol_ ... truct.html

You can use insulating materials to keep any heat in the box, perhaps this is what you want to test?

Louise

yes i would like to use isalating matirals for example glass or Foam (Need stuff found localy at home depote or lows)

solar power898 wrote:yes i would like to use isalating matirals for example glass or Foam (Need stuff found localy at home depote or lows)

Do you intend to eat anything you cook? I would think you could go to Lowes and buy a variety of insulating materials (they come in different "r-values" which measures how good an insulator they are- they are like big sheets of cotton) but I wouldn't recommend eating anything that is cooked with them near by, as they may release chemicals when they get hot. This type of material is sold to make your house more energy efficient- and not to be used in cooking- so they make not be safe. If you are just measuring the temperature of water in the oven, this should be fine. But, if you want to eat something, then it is more difficult.

Note: in one of your posts you said you wanted these materials to absorb heat- they do not absorb heat well, which is why they are good insulators. I'm not sure you really understand your experiment well here...

Louise

Louise

i didnt under stand it at first but im startin to get the idea im trying to make the tempture as high as i can by changing certant thing on the oven this is the project im trying to do http://www.sciencebuddies.com/mentoring ... l?from=TSW

solar power898 wrote:i didnt under stand it at first but im startin to get the idea im trying to make the tempture as high as i can by changing certant thing on the oven this is the project im trying to do http://www.sciencebuddies.com/mentoring ... l?from=TSW

Okay. In a little bit I will write a longer post explaining some of the ideas in more detail so you understand more clearly.

For the variation: "Try different types of insulation between the inner and outer boxes"

You could do this very safely and with easily obtainable materials. {Some designs use foam in this part, which is why I said before you need to be careful about what you used. Some insulators and foams will be hurt somewhat by 200 degree heat, and could produce chemicals when heating.}

Insulation is material which does not absorb heat quickly. This is important, because if it did, it would transfer all the heat from the inside of the box to the outside of the box and your oven would never get hot. Generally, metals transfer heat well, this is why you don't use a metal box.

So, in this set of instructions, your insulating material is 1 layer cardboard, one layer of crushed paper, and a second layer of cardboard.

Basically, you can put anything in that middle part. You could leave it empty (air), use dirt, sand, rocks, etc. Or you could pick one material, and try 3 different sizes of boxes (so you have different thickness of insulator) I would not recommend any sort of plastic, unless it (like the cooking bag) is designed for high heat.

Does this make sense?

Louise

I looked at the links in the science buddies list, and I thought this one explained things quite well.

http://solarcooking.org/intuit1.htm


This link also had some good information:
http://solarcooking.org/solarcooking-faq.htm

Lastly, there is a link from the solar cooking site to a series of questions that need to be answered. While this is just a science fair project to you, many people do use this type of oven to cook. If you want ideas of other experiments and variations you can try, look here:

http://solarcooking.org/research/default.htm

Note: These are actual questions that need answering- no one has done this before... this is science in action.

If you don't understand something in these materials, please do ask us here!

Louise

thank you my research plan is due tomarrow 12/4/o6 then i will start getting to gether my experament[color=darkblue][/color]