Is there an easy and inexpensive way to do calorimetry? Something that comes off-the-shelf ready to use, and doesn't require much skill?
Calorimetry at the high school level?
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Specially when you want to prove COPs above 1 with a claim of non chemical heat source, there’s no way to simplify it without a certainty of your results being dismissed.
You may recall the tantalizing display of Dennis Cravens at one of the NI Weeks (2013) with two brass balls kept in “bath” of aluminum pellets. The power input to the bath was the same yet there was a difference of temperature for the brass balls, and it was caused because the test ball was filled with some deuterium. This is the kind of tests that can garner public interest, but will never gain scientific interest.
http://www.infinite-energy.com/images/pdfs/NIWeekCravens.pdf
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Is there an easy and inexpensive way to do calorimetry? Something that comes off-the-shelf ready to use, and doesn't require much skill?
I built a Mizuno type mass air flow calorimeter, with about 1/2 m3 internal volume. I recommend using foam board walls for such a type and do not use acrylic except for a window if necessary. Several thermocouples and fan power etc. were recorded by arduino every two seconds that I wrote/assembled the software for. With a constant inlet and outlet air flow, and a good seal, basically the whole thing hangs on the delta temperature between inlet and outlet. It is good for 50 to 500 Watts and reasonably hot things with care. A thermo cut-out switch that opens and cuts off heat power if it gets too hot inside is a good idea for foam calorimeters in general. Aluminized polyisocyanate board on the inside and the blue or pink foam board overtop with opposite direction overlapping corners to help seal. Including arduino something like this could be under $500, depending on thermocouples etc.
It can be scaled down a bit, but there are better methods like Seebeck calorimeters for smaller power ranges. -
I built a Mizuno type mass air flow calorimeter,
Sounds like it would make a good Instructible article.
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nstructible article.
Do-it-yourself methodology for calorimeter construction based in Arduino data acquisition device for introductory chemical laboratoriesMany experimental thermochemical laboratories require monitoring temperatures during a reaction or physical procedure. Nowadays, there are many altern…www.sciencedirect.comArduino $40
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My project was more complicated than necessary at the beginning since I began by replicating something (the acrylic Mizuno type calorimeter) and then it was modified after testing it for weak points.
To do it again, knowing what it needs and what is nice but not necessary, and what is necessary would be really easy now.
I used Sylvania incandescent lamps for calibration, up to 5 at a time in a fixture with independent switches so different wattages (50 to 150W each) could be applied in a sequence that makes roughly 50 W steps along a large range. A custom wound 12.5 ohm heater coil was a second calibration device. The actual power consumption, not the rated power of the lamps was used, but the Sylvania rated power was found to be very precise at the rated voltage compared to cheaper brands.
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My project was more complicated than necessary at the beginning since I began by replicating something (the acrylic Mizuno type calorimeter) and then it was modified after testing it for weak points.
To do it again, knowing what it needs and what is nice but not necessary, and what is necessary would be really easy now.
I used Sylvania incandescent lamps for calibration, up to 5 at a time in a fixture with independent switches so different wattages (50 to 150W each) could be applied in a sequence that makes roughly 50 W steps along a large range. A custom wound 12.5 ohm heater coil was a second calibration device. The actual power consumption, not the rated power of the lamps was used, but the Sylvania rated power was found to be very precise at the rated voltage compared to cheaper brands.
I think you should clarify that you were attempting to show that Mizuno’s air flow calorimeter was flawed, specially regarding to the air flow measurements methods themselves. You can’t deny that was your focus.
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I think you should clarify that you were attempting to show that Mizuno’s air flow calorimeter was flawed, specially regarding to the air flow measurements methods themselves. You can’t deny that was your focus.
I did not presume it was flawed. I tested to see if it was reliable, and what sort of errors it could be prone to.
I improved it significantly to the point where it reports 97% of the heat, from beginning at around 80% efficient with the original design. I also determined that acrylic has almost the same specific heat as stainless steel, so it is poor for calorimeter construction because it slows the whole thing down considerably. I reduced the period to arrive at steady state from a significant internal change to a few minutes from the original 45 minutes to an hour. A 20 W change is noticeable in less than 5 seconds now.Almost everything that I did I reported here.
Very few people had constructive criticism or suggestions.
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At 80% heat recovery, a well-sealed corrugated cardboard box will easily replace the acrylic with the same efficiency but will improve the steady state settling period by almost 10 times.
I tested it. -
I think you should clarify that you were attempting to show that Mizuno’s air flow calorimeter was flawed, specially regarding to the air flow measurements methods themselves. You can’t deny that was your focus.
As a reader, I did not get that impression. There had been frequent questions about air-flow calorimeters. (ISTR).
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There had been frequent questions about air-flow calorimeters. (ISTR).
Ascolian Q's were most frequent,,,wrt Mizuno...something about the insignificant figures..
I don;t remember any Q's from Alan Fletcher
the Mizuno flow calorimetry results remained unchanged..despite the Q's and assertions,,no flaw was found in the setup..
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I don;t remember any Q's from Alan Fletcher
Not BY me, but there were questions by others. And some older q's about airflows .. as I recall.
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as I recall.
nothing specific,,,?
there was a detailed spreadsheet of one set of results from Jed which I checked..
as part of a review..
as I recall
with airflows and temperatures..
you can check it if you want,,,
