Thermodynamics B/C

[kendreaditya]

What is the Thermal Conductivity of Aerogel!

[kendreaditya]

I think the aerogel itself is enough for insulation, I don't really think the vacuum on the outside will have any difference since the aerogel should be able to keep in most of the heat.

A vacuum helps the keep the radiation from the heat inside the device, thus the contains more heat.

[what a beauty]

What are the results for your devices so far? What are good some good results?

[LittyWap2]

Does anyone have places to get Aerogel? Please send a link.

[what a beauty]

What is the thermal conductivity of mylar bags and how is it better than normal mylar?

[Person]

Does anyone have places to get Aerogel? Please send a link.

This was previously addressed in the thread.

Could any of you share some reputable links for buying aerogel?

You can get 250cc of granular aerogel from this website: http://unitednuclear.com/index.php?main ... ucts_id=89 for only $13.00 (Have made successful purchases from that site in the past).

250cc might be enough, with a custom shell, to create a 1-2cm thick gel barrier around the beaker, plenty considering how well aerogels insulate. Then again, if you wanted to fill up the entire 3,375 cm3 space it would cost you about $160.

[JonB]

Has anyone tried a vacuum? Would you suggest using that rather than using the mylar bags mentioned earlier? Our plan was to use a vacuum on the outer layer of the device, and on the inner layer, use aerogel which surrounds the beaker. Also, would 3-D printing any parts be more efficient?

We attempted to create a device that kept a vacuum when Thermo was around last event cycle. It was EXTREMELY difficult and we could not keep the vacuum for a prolonged period of time. It may be an implementable idea but we never had success with it and focused our attention to simpler ideas. There are some extremely good insulators out there that can be used for this event.

[kendreaditya]

Has anyone tried a vacuum? Would you suggest using that rather than using the mylar bags mentioned earlier? Our plan was to use a vacuum on the outer layer of the device, and on the inner layer, use aerogel which surrounds the beaker. Also, would 3-D printing any parts be more efficient?

We attempted to create a device that kept a vacuum when Thermo was around last event cycle. It was EXTREMELY difficult and we could not keep the vacuum for a prolonged period of time. It may be an implementable idea but we never had success with it and focused our attention to simpler ideas. There are some extremely good insulators out there that can be used for this event.

What design did you try?

Here is a digram of our device:

[Ashernoel]

Vacuum sealing with Mylar also has the space (quarter inch or so) where it is sealed andciuld waste space. On top of that, a small perforation would ruin the consistency of the device. Even over the course of the year, air will bleed in over time and hurt perfomance.

Because of all these negatives, wouldn’t it be better to create a consistently insulated container with low risk of insulatory degradation and instead focus on prediction score? Best retention between vacuum and fully aerogel or the like will be within s few degrees and that would only gain tenths? Of a point when a faulty prediction could cost 10 times as much.

Idk tho i haven’t tested and these are just my thoughts about vips...

[JonB]

@kendreaditya - This design was similar to what we tried (minus the aerogel). We took inspiration from a vacuum sealed thermos. A couple of practical problems we encountered and that you will encounter if you try this design:

1. It will eventually loose the vacuum pretty much no matter what, as Ashernoel also indicated.
2. How are you going to remove the air from the device to make the vacuum? We used a strong vacuum pump but remember you have to take the vacuum pump off which is a problem. Incorporating a hose connection to the vacuum that will prevent back flow is very difficult due to size limitations. Without a connection, there is no way to connect the vacuum hose well. As SOON as you remove the vacuum pump to try and close that opening, you will lose the vacuum.
3. Also as Ashernoel said, consistency with the device is vital to your success. How will you know that your device even kept the vacuum without some sort of gauge built into the device?

All of that said, I encourage you to try the vacuum design but think about these three items carefully. I hope you have more success then we did with a vacuum design. As stated, we settled on a more classical design last event cycle which worked very well and was very consistent.