Thermal Plate question (turbulence)

sqwib

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• Jan 28, 2010

• #1

Has anyone tried using anything on the underside of the thermal plates to increase efficiency?
And if so, what did you do?

 

Dutch

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• Jan 28, 2010

• #2

??

?? You have me confused on this one SQWIB. Not much you can do with that big ol' plate in the bottom of a Reverse Flow. Tuning plates can be played with on conventional off-sets to adjust where you want it hotter and such but r/f don't have them.

 

sqwib

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To increase heat transfer you would need turbulence, so my thinking was to add a few pieces of angle iron underneath the plate.

 

pineywoods

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• Jan 28, 2010

• #4

If you use 1/4" steel for the plate thats a pretty good thermal mass.

 

sqwib

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• Jan 28, 2010

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Yeah I figured the plate alone was good enough but just wanted to double check before I weld the plate in place.
I know when you make a window box you add baffles to increase air turbulence, this gives you better heat transfer because the air is tumbling through and not just taking the quickest way out.

 

jirodriguez

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• Jan 28, 2010

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I would think with a smoker you might not want turbulence - I am guessing here, but wouldn't that decrease the draw of air you get from your exhaust vent? I was under the impression you want the air to flow smoothly from your intake to your exhaust, as much as possible.

 

sqwib

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I COULD be wrong but from what I understand is that it wont restrict or hinder flow but the turbulence causes better heat transfer.

 

slareau

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• Feb 3, 2010

• #8

I don't have tables or charts in front of me but I doubt that you going to be really dealing with a high enough flow of gas (smoke) to make a turbulent/laminar difference. If anything, adding some angle iron down there will have much more of an impact as a thermal mass than anything else. Granted it has been a few years since I've taken fluid dynamics and heat transfer but I'm pretty sure about this. Sure, baffles will slow down the flow of the hot gas and also act as a heat sink in reverse but I'm not sure a few pieces of angle iron would noticeably improve efficiency. That is assuming you are defining efficiency as the amount of fuel burned for a given period of time.

Best way to know for sure is to try though, worst case scenario is that you have more thermal mass to help with recovery.

Hope this helps