Thermodynamics B/C Build

JonB
Coach
Coach
Posts: 279
Joined: March 11th, 2014, 12:00 pm
Division: C
State: FL

Re: Thermodynamics B/C Build

Postby JonB » March 29th, 2019, 7:32 am

CookiePie1 wrote:
wec01 wrote:
JonB wrote:

I feel that would be so difficult to keep consistent due to the difficulty of making sure there actually is a vacuum created within the device walls. Did they keep the vacuum bag on it during testing??

But, if it works, great!


I didn't see it in action, but it was a rigid container rather than a bag and it had a barometer which I assume helped with consistency.


The problem with homemade vacuum devices is that they are very unpredictable. Sure, it might work really well, but if there's an issue with the vacuum, it leaks and your prediction is messed up.



This was the problem we ran into when Thermo was an event years ago and only natural products could be used as insulation. We honestly put a good amount of time and effort into the idea of a vacuum device but never got it to work as well as we were hoping. Almost impossible to keep the vacuum and very difficult to tell if the vacuum is maintained. I honestly think it is possible, but the amount of time it would take to build a predictable device could (and probably should) be used for testing and data collection of a device that is simple and gives results that are easy to replicate given the same parameters (water volume, temp, etc).

User avatar
someone1580
Member
Member
Posts: 7
Joined: September 29th, 2018, 12:15 pm
Division: C
State: CA

Re: Thermodynamics B/C Build

Postby someone1580 » March 30th, 2019, 9:28 pm

So states are coming up next week and I made a completely new box because of a rules clarification that made my old box's heat retention quite terrible. I wanted to know if a starting temperature of 70 degrees at 125 ml ending at 62.8 is going to be good for state competition

wec01
Member
Member
Posts: 184
Joined: February 22nd, 2019, 4:02 pm
Division: Grad
State: VA

Re: Thermodynamics B/C Build

Postby wec01 » March 30th, 2019, 9:46 pm

someone1580 wrote:So states are coming up next week and I made a completely new box because of a rules clarification that made my old box's heat retention quite terrible. I wanted to know if a starting temperature of 70 degrees at 125 ml ending at 62.8 is going to be good for state competition

That sounds like it'll be fine. I would be more concerned with making sure you can make a good prediction.
2019 Nationals Medals:
4th place Fossils
5th place Sounds of Music
2nd place Thermodynamics

User avatar
CookiePie1
Member
Member
Posts: 205
Joined: February 15th, 2018, 5:05 pm
Division: C
State: NJ
Location: Am I here? Or there? Or both...?

Re: Thermodynamics B/C Build

Postby CookiePie1 » March 31st, 2019, 11:39 am

wec01 wrote:
someone1580 wrote:So states are coming up next week and I made a completely new box because of a rules clarification that made my old box's heat retention quite terrible. I wanted to know if a starting temperature of 70 degrees at 125 ml ending at 62.8 is going to be good for state competition

That sounds like it'll be fine. I would be more concerned with making sure you can make a good prediction.


You should probably be cramming in a bunch of trials right now, with a new box. Just make sure the box cools in between and that you're getting consistent results.
South Brunswick High School '22
2019 Events: Thermodynamics, Protein Modeling, Mission Possible, Wright Stuff

Reality is merely an illusion, albeit a very persistent one.
-Albert Einstein

Check out my userpage!

sciencekid27
Member
Member
Posts: 16
Joined: March 23rd, 2019, 2:51 pm
State: -
Location: multisciolyverse

Re: Thermodynamics B/C Build

Postby sciencekid27 » April 3rd, 2019, 6:51 pm

Just wondering, would it be better to have a higher start temperature, maybe 67-72, than to have a lower start temperature, around 60? I know that if you have a higher start temperature, the water decreases to a lower end temperature. For example, if you start at 70, it may drop to 55 (random value btw), which is a 15 degree drop. However, if you start at 60, it would drop to maybe around 50, which is a 10 degree drop. Which one of these is better in terms of the heat score in the competition? Thanks!
1/3 inquirer, 1/3 studier, 1/6 lab-doer, and 1/6 builder

User avatar
CPScienceDude
Member
Member
Posts: 140
Joined: December 12th, 2018, 2:40 pm
Division: C
State: IN
Location: A weird limbo between div b and c

Re: Thermodynamics B/C Build

Postby CPScienceDude » April 3rd, 2019, 6:55 pm

sciencekid27 wrote:Just wondering, would it be better to have a higher start temperature, maybe 67-72, than to have a lower start temperature, around 60? I know that if you have a higher start temperature, the water decreases to a lower end temperature. For example, if you start at 70, it may drop to 55 (random value btw), which is a 15 degree drop. However, if you start at 60, it would drop to maybe around 50, which is a 10 degree drop. Which one of these is better in terms of the heat score in the competition? Thanks!

Ultimately it depends on your box, but personally my box preformed exceptionally better with lower starting temps. In terms of competition, it really doesn’t matter because most other teams’ boxes will also follow this pattern.
CPHS 23'
Projected 2020 events: Ornithology, Boomilever, and Forensics
Member of the Builder Cult
About me! https://scioly.org/wiki/index.php/User:CPScienceDude

sciencekid27
Member
Member
Posts: 16
Joined: March 23rd, 2019, 2:51 pm
State: -
Location: multisciolyverse

Re: Thermodynamics B/C Build

Postby sciencekid27 » April 3rd, 2019, 6:58 pm

Also, the k value that is closest to zero is best, right?
1/3 inquirer, 1/3 studier, 1/6 lab-doer, and 1/6 builder

User avatar
CPScienceDude
Member
Member
Posts: 140
Joined: December 12th, 2018, 2:40 pm
Division: C
State: IN
Location: A weird limbo between div b and c

Re: Thermodynamics B/C Build

Postby CPScienceDude » April 3rd, 2019, 6:59 pm

sciencekid27 wrote:Also, the k value that is closest to zero is best, right?

Yup
CPHS 23'
Projected 2020 events: Ornithology, Boomilever, and Forensics
Member of the Builder Cult
About me! https://scioly.org/wiki/index.php/User:CPScienceDude

sciencekid27
Member
Member
Posts: 16
Joined: March 23rd, 2019, 2:51 pm
State: -
Location: multisciolyverse

Re: Thermodynamics B/C Build

Postby sciencekid27 » April 8th, 2019, 12:17 pm

What do y'all think is a good prediction for nats? We are getting about 0.5 off in practice.
1/3 inquirer, 1/3 studier, 1/6 lab-doer, and 1/6 builder

User avatar
CookiePie1
Member
Member
Posts: 205
Joined: February 15th, 2018, 5:05 pm
Division: C
State: NJ
Location: Am I here? Or there? Or both...?

Re: Thermodynamics B/C Build

Postby CookiePie1 » April 8th, 2019, 12:25 pm

sciencekid27 wrote:What do y'all think is a good prediction for nats? We are getting about 0.5 off in practice.


That's really good! I mean, at nats, you'd probably want to get within 1.5 degrees. Otherwise, you should be pretty much fine if you can repeat those results.
South Brunswick High School '22
2019 Events: Thermodynamics, Protein Modeling, Mission Possible, Wright Stuff

Reality is merely an illusion, albeit a very persistent one.
-Albert Einstein

Check out my userpage!

wec01
Member
Member
Posts: 184
Joined: February 22nd, 2019, 4:02 pm
Division: Grad
State: VA

Re: Thermodynamics B/C Build

Postby wec01 » April 8th, 2019, 2:28 pm

CookiePie1 wrote:
sciencekid27 wrote:What do y'all think is a good prediction for nats? We are getting about 0.5 off in practice.


That's really good! I mean, at nats, you'd probably want to get within 1.5 degrees. Otherwise, you should be pretty much fine if you can repeat those results.


Yeah, with 0.5 degrees you're only losing a bit over a point, and it's also going to be very difficult to do much better consistently, so I'd say you're in a good spot.
2019 Nationals Medals:
4th place Fossils
5th place Sounds of Music
2nd place Thermodynamics

sciencekid27
Member
Member
Posts: 16
Joined: March 23rd, 2019, 2:51 pm
State: -
Location: multisciolyverse

Re: Thermodynamics B/C Build

Postby sciencekid27 » April 19th, 2019, 1:25 pm

How are you guys making predictions for 5 mL increments? We don't really have time to test every 5 mL increment from 75 to 125 (there are 11 increments)! Is there any way to use to 25 mL increments and maybe perform a weighted arithmetic or geometric average?
1/3 inquirer, 1/3 studier, 1/6 lab-doer, and 1/6 builder

wec01
Member
Member
Posts: 184
Joined: February 22nd, 2019, 4:02 pm
Division: Grad
State: VA

Re: Thermodynamics B/C Build

Postby wec01 » April 19th, 2019, 1:37 pm

sciencekid27 wrote:How are you guys making predictions for 5 mL increments? We don't really have time to test every 5 mL increment from 75 to 125 (there are 11 increments)! Is there any way to use to 25 mL increments and maybe perform a weighted arithmetic or geometric average?

Yeah, you can definitely interpolate the data, but whether you use some sort of regression, average, or something else is up to you since many different methods will get reasonably close. I would still suggest testing a few more volumes even if you don't have time for all of them; the more data you have the better the prediction will be.
2019 Nationals Medals:
4th place Fossils
5th place Sounds of Music
2nd place Thermodynamics

satvik03
Member
Member
Posts: 32
Joined: January 7th, 2019, 2:25 pm
Division: B
State: NJ

Re: Thermodynamics B/C Build

Postby satvik03 » April 20th, 2019, 8:20 am

You can also try to connect two independent variables.
Community 2018-2019
2018-2019 Events:
LISO/Rustin/Regs/Garnet/Cornell/States/Nats!
Thermo: 1/1/x/x/2/5/12
Circuit: 2/3/x/4/10/1/11
Experimental Design: 2/1/1/10/5/1/13
2018-2019 Medal Count: 15
National "What Are You Trying To Tell Me" Champion! (lol)

UTF-8 U+6211 U+662F
Exalted Member
Exalted Member
Posts: 1465
Joined: January 18th, 2015, 7:42 am
Division: C
State: PA

Re: Thermodynamics B/C Build

Postby UTF-8 U+6211 U+662F » April 21st, 2019, 6:32 pm

satvik03 wrote:You can also try to connect two independent variables.

Can you explain what you mean by this


Return to “Thermodynamics B/C”

Who is online

Users browsing this forum: No registered users and 1 guest