Formula for relating time and heat gained for closed system

AI Thread Summary
The discussion focuses on creating a table to illustrate the relationship between outside temperature and the time it takes for the temperature inside two different closed systems to reach a specific temperature. The systems contained frozen goods and were tested under identical conditions, with temperature readings taken every minute after being removed from a cooled environment. A suggestion was made to use Newton's law of cooling to derive a formula for the table, while excluding variables like wind and humidity to simplify the data for consumer understanding. Concerns were raised about the potential variability introduced by ignoring factors such as forced convection, but the consensus is that the controlled conditions justify the approach. Ultimately, the aim is to visually demonstrate that one product warms up slower than the other, providing a clear comparison for consumers.
Allen Dowe
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This is for work. I need to make a table for a client.
What we did: had two different closed systems, only difference is material. We had frozen goods in both containers, the containers were both removed from the cooled surroundings they were in and placed outside. The temperatures were taken for both containers every minute.
What I need is a formula or something to help me create a table that will show a relationship between the outside temperature and the time it takes the temperature inside the system to get to a certain temperature (not yet chosen). I will be making 2 Tables one for each container.
Please help if you can!
NOTE: exclude variables like wind, humidity, pressure, being that this table is meant for consumers to see. they do not need exacts.
 
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The data you collected has the information you need. Have you plotted the data in excel or sim.? Add a trendline, the formula for that trendline should follow Newtons law of cooling:
http://formulas.tutorvista.com/physics/Newton-s-law-of-cooling-formula.html
http://en.wikipedia.org/wiki/Convective_heat_transferIgnoring wind may be a poor assumption, forced convection heat transfer can be orders of magnitude greater than natural convection heat transfer (that's why we blow on hot food and cars have radiator fans etc)
 
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Thank you sir, I appreciate it! And yes i agree, but it would leave me with too much variability to make a chart I think. What do you say?
 
Explain 'too much variability'.
If your data is poor then anything you glean from it will also be poor.
 
The goal is for consumers to see the comparison of our product to their current product. Since the conditions were exact for the two systems (held at same time/place) i feel it should be alright to assume fair conditions.

By too much variability I mean is there would be sooo much extra data that would almost be considered irrelevant from a consumer perspective. Your thoughts?
 
I don't understand what you're saying.
It's up to you to decide what data to give the consumer. Give them as much as you see fit.
I think simply graphing what you have will be fine. The consumer will see your new product warms up slower than the current.
Like this:
CoolingFull.png


(obviously, your products are increasing temp rather than cooling)
 
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