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Re: Thermodynamics B/C Build

Posted: December 12th, 2018, 6:47 pm
by CPScienceDude
CookiePie1 wrote:
CPScienceDude wrote:
UTF-8 U+6211 U+662F wrote: The water always loses temperature when you pour it unfortunately. I would recommend pouring the water and then sticking your thermometer in. I'm not sure about this year, but last year, you were allowed to bring a thermometer to the competition and record the temperature after the water was poured. If that's still allowed, I would definitely recommend doing that.

By the way, are you pouring and then putting the beaker in your device, or are you keeping the beaker in your device and then pouring the water in?
I keep the beaker in my device the pour the water into the beaker directly. The rules don't explicitly say you should bring a thermometer, rather just saying that each team can bring tools and supplies.
See rule 4.e. regarding the thermometer. We always lost a large amount of heat in te process of measuring and pouring into the beaker. However, if you have this problem, other teams will also have this problem. Therefore I wouldn't worry about it too much.
Yeah, that's what I was thinking, but I was more worried about the predictions. Because this is my first year on this event, I was thinking that there is a different way the event supervisors dispense water so that heat was isn't so severe. Anyway, thank's for the help!

-CPScienceDude

Re: Thermodynamics B/C Build

Posted: December 13th, 2018, 10:25 am
by CPScienceDude
I've been seeing alot about the magical properties of aerogel. I've done some research, but I haven't come to a good conclusion on one thing.

A. What's the difference between Aerogel and Pyrogel?
B. Which one is better?

Thanks for any help!

-CPScienceDude

Re: Thermodynamics B/C Build

Posted: December 13th, 2018, 6:03 pm
by TheChiScientist
CPScienceDude wrote:I've been seeing alot about the magical properties of aerogel. I've done some research, but I haven't come to a good conclusion on one thing.

A. What's the difference between Aerogel and Pyrogel?
B. Which one is better?

Thanks for any help!

-CPScienceDude
Main differences here.
1. Aerogel is more readily available on the civilian market (A.K.A us) while Pyrogel is harder to acquire unless you know someone in the industry directly.
2. Pyrogel is Hydrophobic! Major plus as Aerogel is not and well... We use water in this event. ¯\_(ツ)_/¯
3. Aerogel comes in smaller quantities while Pyrogel comes in HUGE amounts.
4. ^This also means $$$$$ is through the roof. O_o (I'd say over 1k...)
5. Overall Aerogel is better due to accessibility and cost. Yet the Pyrogel has great thermal properties but is near impossible to acquire. :(

Re: Thermodynamics B/C Build

Posted: December 13th, 2018, 8:21 pm
by CPScienceDude
So my parents aren't going for it. Would this work as a cheaper alternative?

https://www.amazon.com/gp/product/B07DL ... DX2NQ79J1G

Re: Thermodynamics B/C Build

Posted: December 13th, 2018, 8:55 pm
by knightmoves
CPScienceDude wrote:Ok so I think I need a better way to test my device. I microwave 95 mL of water. I take it out at boiling. I stick my digital thermometer in and I wait until the water reaches 75C. I pour the water in, seal my device, and plug the hole. I put the thermometer back in and it looses 10 degrees C in about 30 seconds.
That sounds normal enough.

You can break it down, though - how much of the heat loss is the pouring process vs how much is the thermal mass of the beaker etc. For example, to eliminate the thermal mass of the beaker, pre-heat your beaker with boiling water and perform a test. This doesn't help you with your device, but it tells you whether the heat capacity of the beaker is a significant effect. And so on.

Re: Thermodynamics B/C Build

Posted: December 14th, 2018, 6:27 am
by TheChiScientist
CPScienceDude wrote:So my parents aren't going for it. Would this work as a cheaper alternative?

https://www.amazon.com/gp/product/B07DL ... DX2NQ79J1G
Per the Div B requirements, you would need to cut the bag to 20cmx20cm which would compromise the Aerogel bag thus rendering it non-hydrophobic...
If you can find a smaller packet this would be a great solution but finding Aerogel to purchase in the first place is pretty hard.

Re: Thermodynamics B/C Build

Posted: December 14th, 2018, 8:51 am
by CPScienceDude
TheChiScientist wrote:
CPScienceDude wrote:So my parents aren't going for it. Would this work as a cheaper alternative?

https://www.amazon.com/gp/product/B07DL ... DX2NQ79J1G
Per the Div B requirements, you would need to cut the bag to 20cmx20cm which would compromise the Aerogel bag thus rendering it non-hydrophobic...
If you can find a smaller packet this would be a great solution but finding Aerogel to purchase in the first place is pretty hard.
Well I would wrap it around the beaker and fold the excess.

< 12cm to the bottom of beaker measurement

Posted: December 17th, 2018, 8:01 am
by drcubbin
Heads up on rule 3.a. - At LISO we lost points for being > 12cm to the inside bottom beaker surface mark. When we came back, I checked and measuring vertically up and down we were < 12cm, but if you allow the thermometer to lay on an angle (as it normally does), it was indeed > 12cm. So make sure you are measuring just as the thermometer will sit in the box. At least that is why I think we lost points. Live and learn.

Re: < 12cm to the bottom of beaker measurement

Posted: December 17th, 2018, 3:05 pm
by MattChina
drcubbin wrote:Heads up on rule 3.a. - At LISO we lost points for being > 12cm to the inside bottom beaker surface mark. When we came back, I checked and measuring vertically up and down we were < 12cm, but if you allow the thermometer to lay on an angle (as it normally does), it was indeed > 12cm. So make sure you are measuring just as the thermometer will sit in the box. At least that is why I think we lost points. Live and learn.
What? I don't understand what you're saying, how does the thermometer have anything to do with the beaker position?

Re: Thermodynamics B/C Build

Posted: December 17th, 2018, 4:07 pm
by JoeyC
There is a rule stating that the bottom of the beaker must be less than 12 cm from the top of the hole in your box, in order to allow the thermometer/probe to be read. The above mentioned person is pointing out that it might have been measured inaccurately in their invitational; that the 12 cm was counted instead of vertically, at an angle, so that they would be in violation of this rule.