Thermodynamics B/C

[emmafl18]

I had not read the ice bit very closely as I was still hung up on the large opening.
The advantage of adding ice water is you lower the temp of the water in the beaker, so it does not loose as much heat (differential temperatures). I will have to look at the points gained by adding it vs not adding it. If your beaker water is close to the same temp as the air around it, you will have a very very low heat transfer to any of the three methods.

With this in mind, and the fact that it's easier to keep something warm, warm vs keeping something hot, hot, wouldn't it be more beneficial point wise in the heat retention portion to add the ice water, assuming you could predict the final temperature fairly accurately?

[CVMSAvalacheStudent]

I think that they are putting more of an emphasis on the estimation part rather than the heat retention.

I agree with you.

[WhatScience?]

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:

What is the outer part made of (lid walls) etc. Because if you want it to last, it should be durable.

[Ashernoel]

R value is a function of thermal conductivity, right? Is it in such a way that given two insulators or equal thickness half the thermal conductivity means twice the r value? Or...?

[WhatScience?]

I had not read the ice bit very closely as I was still hung up on the large opening.
The advantage of adding ice water is you lower the temp of the water in the beaker, so it does not loose as much heat (differential temperatures). I will have to look at the points gained by adding it vs not adding it. If your beaker water is close to the same temp as the air around it, you will have a very very low heat transfer to any of the three methods.

With this in mind, and the fact that it's easier to keep something warm, warm vs keeping something hot, hot, wouldn't it be more beneficial point wise in the heat retention portion to add the ice water, assuming you could predict the final temperature fairly accurately?

See but do we know the temperature of the ice water.

And also, will the 5 points really be worth the risk?

[wzhang5460]

I don't really know if the five points you gain will cancel out the points you lose in the HRF part of the scoring section. Also, there might be an inconsistency with the exact amount of ice water you put in (it can be off by a couple of ml) so in my opinion there are too many factors with the Ice Water bonus that it isn't really worth the five points. Also, doing the bonus would result in a lot of additional hours pouring out ice water into the beaker, testing, experimenting with the amount of ice water to add, all for 5 points that can be easily gained in the test section which is what this event is mainly based on.

[WhatScience?]

@Chalker- would it be possible at this stage to get an ice water temp added in. Or was that deliberately left out to make the decision harder and have the possibility of victory with both.

[chalker]

@Chalker- would it be possible at this stage to get an ice water temp added in. Or was that deliberately left out to make the decision harder and have the possibility of victory with both.

I don't understand what you are asking.

[Person]

@Chalker- would it be possible at this stage to get an ice water temp added in. Or was that deliberately left out to make the decision harder and have the possibility of victory with both.

I don't understand what you are asking.

Doesn't ice water stay at 0 C?

[Unome]

@Chalker- would it be possible at this stage to get an ice water temp added in. Or was that deliberately left out to make the decision harder and have the possibility of victory with both.

I don't understand what you are asking.

Doesn't ice water stay at 0 C?

Yes, if water and ice coexist and are sufficiently mixed, the temperature is zero, since, theoretically, all excess heat is going toward melting the ice.