Determining the energy released by a flame

  • #1
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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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  • #2
phinds
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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?
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?
 
  • #3
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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
 
  • #4
phinds
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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?
 
  • #5
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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
 
  • #7
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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.
 
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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
 
  • #9
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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
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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
phinds
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@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
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@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
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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
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@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
phinds
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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
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Nicely done.
Thank you very much for all your help
 

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