Determining the energy released by a flame

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Discussion Overview

The discussion revolves around determining the energy released by a compost pile, specifically focusing on how to measure or calculate the heat energy produced without conducting a lengthy experiment. Participants explore various methods and considerations related to thermal conductivity, heat transfer, and the specifics of the experimental setup.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • One participant suggests using water to measure heat released but finds it impractical due to time constraints.
  • Another participant questions the ambiguity of the problem statement, particularly regarding the size of the space into which heat is radiating.
  • A participant proposes treating the heat source as a half sphere and applying Fourier's law to analyze heat conduction.
  • Concerns are raised about the clarity of the problem statement and the importance of providing complete information for effective assistance.
  • There is a discussion about the etiquette of editing posts in the forum, with some participants expressing frustration over changes made to the original post after responses were given.
  • A participant acknowledges the need for a clearer problem description and suggests starting a new thread for better organization.

Areas of Agreement / Disagreement

Participants express disagreement regarding the clarity and completeness of the problem statement. There is no consensus on how to approach the calculation of energy released, and various methods are proposed without agreement on their effectiveness.

Contextual Notes

The discussion highlights limitations related to the ambiguity of the problem, the dependence on specific definitions (e.g., size of the space), and the unresolved nature of the proposed methods for calculating heat energy.

Who May Find This Useful

This discussion may be useful for individuals interested in thermodynamics, heat transfer, or experimental physics, particularly those exploring practical methods for measuring energy release in biological or composting processes.

AamsterC2
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I've found a lot about using water to find the amount of heat released by something but the experiment I want to run would take about two weeks to complete so that's probably not a viable solution for me. I know what the temperature will be and that it will remain mostly constant, is there anyway to find the amount of heat energy released if I know the temperature of the heat source and surrounding air? The heat source for this experiment is a compost pile (1 cubic meter), I know that the inside of the pile will reach approximately 50C for 2 weeks or so. Right now it's winter so the temperature will stay around 0C (average). The thermal conductivity of compost can vary greatly but in this case an average that would apply is 0.3 W/m
 
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AamsterC2 said:
I've found a lot about using water to find the amount of heat released by something but the experiment I want to run would take about two weeks to complete so that's probably not a viable solution for me. I know what the temperature will be and that it will remain mostly constant, is there anyway to find the amount of heat energy released if I know the temperature of the heat source and surrounding air?
This seems to me to be an utterly ambiguous problem statement. For example, is the heat source radiating into a space the size of a breadbox or a space the size of Yankee Stadium? Do you think it matters?
 
phinds said:
This seems to me to be an utterly ambiguous problem statement. For example, is the heat source radiating into a space the size of a breadbox or a space the size of Yankee Stadium? Do you think it matters?
For this no, it will be in an open area so there won't be any build up of heat around it
 
AamsterC2 said:
For this no, it will be in an open area so there won't be any build up of heat around it
And do you think that fact now makes the problem statement fully explicated?
 
phinds said:
And do you think that fact now makes the problem statement fully explicated?
Well as I said I am unaware of anyway to solve this problem other than using the heat source to raise the temperature of water which I don't see as being viable in this situation, I do not know what kind of information would be needed to solve a problem like this but I could more than likely provide it if you know of some sort of equation for it or some other way to test how much energy is produced
 
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I'm assuming that considering the shape to be a half sphere for simplicities sake you could then solve it by treating it as a conduction problem and solving with Fourier's law where the outer section at a cooler temperature would be considered the wall blocking heat flow
 
AamsterC2 said:
you could then solve it

You seem to think solving it is our responsibility. It isn't.

And even if it were, it's so vague that it's unanswerable. If you want help, I'd take Phinds' advice and write a complete description of the problem.
 
Vanadium 50 said:
You seem to think solving it is our responsibility. It isn't.

And even if it were, it's so vague that it's unanswerable. If you want help, I'd take Phinds' advice and write a complete description of the problem.
I apologize if it sound as if I wanted you to solve it for me, I'm not that incapable and was using not trying to imply somebody should solve it for me simply that you, I, or anyone else could then possibly solve a problem like this by applying Fourier's Law. I do not know if that is the correct way to go about this though which is why I'm asking how it should be done
 
AamsterC2 said:
The heat source for this experiment is a compost pile (1 cubic meter), I know that the inside of the pile will reach approximately 50C for 2 weeks or so. Right now it's winter so the temperature will stay around 0C (average). The thermal conductivity of compost can vary greatly but in this case an average that would apply is 0.3 W/m
What else do you need to know?
 
  • #10
Bystander said:
What else do you need to know?

The OP has edited his post. Originally none of this information was there. Now we all look stupid for asking. Well done, AamsterC2! You made all the people capable of helping you look like jerks! I guess we will see if it is an effective strategy.
 
  • #11
@AamsterC2, it's very bad form to go back and edit a post that people have responded to. You should instead just add the information in a NEW post to avoid confusion. You can even, if you wish, quote your own post into a new post but edit it, prefacing it with a note that you have amended it for clarity.
 
  • #12
phinds said:
@AamsterC2, it's very bad form to go back and edit a post that people have responded to. You should instead just add the information in a NEW post to avoid confusion. You can even, if you wish, quote your own post into a new post but edit it, prefacing it with a note that you have amended it for clarity.
OK, I was unaware of that, I'll change my original post to what it was and post any relavent information I think of in a new post
 
  • #13
Vanadium 50 said:
The OP has edited his post. Originally none of this information was there. Now we all look stupid for asking. Well done, AamsterC2! You made all the people capable of helping you look like jerks! I guess we will see if it is an effective strategy.
You do realize it's possible that this is the 3rd question I've ever asked on here and may have simply been trying to put relevant information where anyone could find it, not trying to make anyone seem like a jerk. Please calm down, I apologize
 
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  • #14
phinds said:
@AamsterC2, it's very bad form to go back and edit a post that people have responded to. You should instead just add the information in a NEW post to avoid confusion. You can even, if you wish, quote your own post into a new post but edit it, prefacing it with a note that you have amended it for clarity.
It seems I am now unable to edit my first post, should I delete this entire topic and create it again with the needed information? Also I apologize for my ignorance when it comes to the etiquette for this forum
 
  • #15
AamsterC2 said:
It seems I am now unable to edit my first post, should I delete this entire topic and create it again with the needed information? Also I apologize for my ignorance when it comes to the etiquette for this forum
No problem. We're all new when we're new :smile:

You can only edit posts for a limited amount of time. I'd suggest that you carefully formulate EXACTLY the problem you are trying to solve, with all relevant factors, and start a new post with that since this one has become a bit muddled. Once that is done, you should put a post in this thread linking to the new thread and "report" that new post, asking a moderator to close this thread since you've started a new one. Sounds more complicated than it is.
 
  • #18
phinds said:
Nicely done.
Thank you very much for all your help
 

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