Zett Vampyre Posted March 24, 2009 Share Posted March 24, 2009 Hi guys, this is my first post here, I hope to have fun here. So, I need help with my grade 7 heat project, I need to make a thermos with a water bottle and other house hold items. The teacher will put hot water in each person's project, and after a certain period of time, will measure the temperature of the water, and the group with the warmest water wins. I'm thinking of wrapping the whole bottle with thick yarn first, put a layer of Styrofoam under the bottle, and cut a hole into two Styrofoam bowls and put packing peanuts/ newspaper balls in the bowls and taper the two bowls together and slide it over the bottle where the circle is. Then wrap the whole thing in foil and cling wrap. Is this a good idea? All replies appreciated. 1 Link to comment Share on other sites More sharing options...
Kaeroll Posted March 24, 2009 Share Posted March 24, 2009 Seems decent... I'd also recommend a nice thick layer of tinfoil around it. -1 Link to comment Share on other sites More sharing options...
Zett Vampyre Posted March 24, 2009 Author Share Posted March 24, 2009 Thanks, I was planning on doing that. Link to comment Share on other sites More sharing options...
samtheflash82 Posted March 25, 2009 Share Posted March 25, 2009 making a real "thermos" is going to be extremely difficult, if not impossible using household items. This is because a true thermos has 2 layers, the outer is a shiny, reflective layer to prevent radiant heat loss, the inner is an insulated layer to prevent conductive heat loss. Between the two is the tricky part; there is a vacuum to prevent convective heat loss. Creating a vacuum using household items is not feasible. Tell that to your teacher. 1 Link to comment Share on other sites More sharing options...
Zett Vampyre Posted March 25, 2009 Author Share Posted March 25, 2009 I know. We just have to keep the liquid warmest for 5 min. Link to comment Share on other sites More sharing options...
insane_alien Posted March 25, 2009 Share Posted March 25, 2009 it doesn't NEED a vacuum, yes it would be good but its not going to happen. the killer is going to be convection, do what you can to prevent air circulating inside the insulation. the second biggest factor is conduction. you'll want to have as little direct contact area with the inside chamber as possible(but without letting convection happen) and any contact should be done with low conductivity materials. radiative heat transfer will be negligible so you don't have to make any shiny parts. if you were dealing with liquid nitrogen or molten metal then yes, radiative heat transfer would be important. 1 Link to comment Share on other sites More sharing options...
Zett Vampyre Posted March 26, 2009 Author Share Posted March 26, 2009 Will paper mache over the whole thing help? Link to comment Share on other sites More sharing options...
insane_alien Posted March 26, 2009 Share Posted March 26, 2009 perhaps as an outer casing Link to comment Share on other sites More sharing options...
Zett Vampyre Posted March 26, 2009 Author Share Posted March 26, 2009 Ya, I was thinking of that. Link to comment Share on other sites More sharing options...
Lovecraft Posted March 28, 2009 Share Posted March 28, 2009 If it's a test to keep the water hottest for 5 minutes, could you use a meterial that heats the water bottle via chemical reaction like a hand warmer? That's what I'd do. I mean it's for 5 mins, not 24 hours. Is that cheating? It is a valid way of keeping the water hot, you are just putting energy into the system rather than trying to keep it from escaping in my scenario. Link to comment Share on other sites More sharing options...
insane_alien Posted March 28, 2009 Share Posted March 28, 2009 i think that would break the purpose of the challenge which is to provide the best insulation rather than who can stick a heater on it. Link to comment Share on other sites More sharing options...
Lovecraft Posted March 28, 2009 Share Posted March 28, 2009 Yeah, you are right, my other option of sticking the water bottle in a thermos probably defeats the purpose too. Link to comment Share on other sites More sharing options...
Zett Vampyre Posted March 28, 2009 Author Share Posted March 28, 2009 Yeah, you are right, my other option of sticking the water bottle in a thermos probably defeats the purpose too. I thought of that too, and wrapping it in foil, but I was bored, so I decided I'll just build it to keep me busy. Link to comment Share on other sites More sharing options...
insane_alien Posted March 28, 2009 Share Posted March 28, 2009 foil won't do much. it can do stuff against thermal radiation but that is nowhere near your biggest heat loss vector. foil doesn't really help slowdown conduction and convection. Link to comment Share on other sites More sharing options...
cameron marical Posted March 29, 2009 Share Posted March 29, 2009 try to make where the water is airtight, and try to make it so there isnt much air in it. i think thatd help.along with several compacted layers. Link to comment Share on other sites More sharing options...
TheSchoolHelper Posted November 3, 2009 Share Posted November 3, 2009 Well I'm doing the same project right now and our group has started the base of it.So we got a glass jar and first wrapped it around with tin foil.After that wrap that layer with black duct tape because it will absorb the heat. After that get duct tape and put cotton balls on it and put the thermos. You can put tin foil in side but that is a option. You can also put styrofoam inside.I would also recommend to put dead air inside so the heat can't escape. That is what I'm doing and I will message you my mark when I'm done with the thermos. I hope I helped a lot of people and Thanks. Link to comment Share on other sites More sharing options...
hermanntrude Posted November 3, 2009 Share Posted November 3, 2009 i'm concerned about the black duct tape. It will absorb the heat, you're right, but why do you want it to be absorbed? surely you want it to be NOT absorbed. You want the heat to stay in the water. As was stated previously the most important thing is to prevent covection. Perhaps that can be done by ensuring there's no air inside? Link to comment Share on other sites More sharing options...
DrP Posted November 3, 2009 Share Posted November 3, 2009 The polystyene foam you mentioned sounds best to me. And as people have said above - stop air flowing in and out of the stytem. Link to comment Share on other sites More sharing options...
Phi for All Posted November 3, 2009 Share Posted November 3, 2009 I used to sell a radiant barrier for home attic insulation, and it was nothing more than reflective foil sandwiching a mylar center (the plastic kept the two sheets of foil from touching and conducting heat). We were told that (back then) this was how spacesuits were designed (but with several more layers). I wonder how the results of the experiment would be if you simply wrapped a plastic bottle with aluminum foil (try not to wrinkle it too much), then did a layer of clear plastic wrap (Glad wrap), then another of tinfoil, more clear wrap and so on, until you have 7-10 layers? This would probably be the easiest and cheapest method if it worked well. You'd need to pay close attention to the mouth and lid, making sure they had just as much insulation. Link to comment Share on other sites More sharing options...
deadshot Posted December 4, 2012 Share Posted December 4, 2012 ok how do you make a thermos and what supplies do you need HHHHHHHHHHHHEEEEEEEEEEEEEEEELLLLLLLLLLLLLLLLLLLLLPPPPPPPPPPPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! MMMMMMMMMMMMMMMMMEEEEEEEEEEEEEEEEEE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Link to comment Share on other sites More sharing options...
Abhay.K Posted December 4, 2012 Share Posted December 4, 2012 do try wrapping the bottle with wool, it helps in trapping heat Link to comment Share on other sites More sharing options...
EmCat334 Posted April 5 Share Posted April 5 I have a grade 7 science project that requires this too. It's based on performance, appearance, and practicality. This is what I have so far: Any advice? Link to comment Share on other sites More sharing options...
Sensei Posted April 5 Share Posted April 5 (edited) 42 minutes ago, EmCat334 said: Any advice? Use styrofoam.. https://en.wikipedia.org/wiki/Polystyrene Edited April 5 by Sensei Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now