MIZUNO REPLICATION AND MATERIALS ONLY

Regarding the earlier discussion of calorimeter sensitivity, the increase of voltage to the blower fan from 8.55 V to 10.45 V results in almost exactly a 2 W increase in fan power consumption, which is easily discernible with a 0.2 C delta T increase (at this low inlet air temperature).

Keep in mind that the air velocity has also increased, so the delta T at the old air velocity (basically impossible to test) might be higher.

The fan is currently consuming 5.8 W, which leads to a 0.45 C delta T.

So it is remarkably sensitive.

My current estimate is a delta T of about 7 C above the current (13.5 or so) delta T, about a 20 C delta T target for 100 W excess which can be simulated by first reaching the standard 210-ish W input at steady state, and then raising the input power to the 300 W level and waiting for steady state to reset.

I need to build a big ugly spreadsheet for the vane vs hot wire anemometer data and heat calculations.

Quote from RobertBryant

5.8 W, which leads to a 0.45 C delta T.

By your calculation.. at 10C input..

5.8W corresponds to 0.45C or to ~0.58C?

The fan 5.8 W at 10.45 V corresponds to delta 0.45 C, and the fan 3.76 W at 8.55 V corresponds to delta 0.25 C .

My estimate is based more on the 210 W calibration delta and preventing excess heat results from back of envelope calculations and could be a bad estimate...

Back of envelope = standard mobile phone calculator.

Quote from RobertBryant

Just a small detail... the fan 5.8 W includes perhaps 1-1.5 W of heat from the mot0r which goes out to the exterior of the airbox.

Maybe. The fan is the only uninsulated part of the assembly.

Still probably pretty easy for that high velocity air to grab most of the 5.8 W without difficulty. Probably harder to scoop all the 3.76 W, because it would take so long for that to heat the fan enough to transfer heat to the air.

I did a 210 W steady to 310 W steady and almost back to 200 W steady state. 100 W delta T looks to be about 5 C which corresponds well with the below image from Jed.

I attached and sealed the 70 mm vane anemometer directly to the outlet tube with a little wider spacer-adapter and it reports almost exactly what it did yesterday, which is almost exactly 7.0 m/s. Much higher than every single data point on the hot wire traverse group which looks to average maybe 4.5 m/s. (I haven’t averaged the 33 points yet, but there are two 6.3’s (maximum T) and about a third of the points are less than half of that.)

It smells like I cooked off some input wire insulation inside the big tube on the 310 W run. It can’t really go anywhere so it should be OK. The inner cartridge was around 700 C.

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JedRothwell ,

Is it possible to get the steady state delta T associated with each of the calibration and excess periods reported from the Saito work?

Quote from Paradigmnoia

Is it possible to get the steady state delta T associated with each of the calibration and excess periods reported from the Saito work?

You mean the temperature difference between the outlet and inlet air. That is what is shown in the 500 W calibration:

I wrote "Arbitrary units" in the left Y-axis, but those are actually degrees, volts and so on. The outlet temperature is show in the brown line, inlet on the next lower blue line. They are pretty stable from 100,000 s to the end (116,790). The values taken from the spreadsheet are:

Inlet temperature average: 20.33, standard deviation 0.08

Outlet temperature average: 40.71, standard deviation 0.09

20.38 difference

I do not have spreadsheets for the other graphs.

Check out this delta T to CFM online simulator. All in imperial measurements but seems to work.

You have to scroll down a bunch to the image with the heater element in the middle and dials around it, which have adjustable settings. The heading is Power Flow Rate Visualized.

https://farnam-custom.com/resources/calculators

Edit: Somehow a quote from a Jed ended up in the middle of the post, now removed.

Quote from JedRothwell

You mean the temperature difference between the outlet and inlet air. That is what is shown in the 500 W calibration:

I wrote "Arbitrary units" in the left Y-axis, but those are actually degrees, volts and so on. The outlet temperature is show in the brown line, inlet on the next lower blue line. They are pretty stable from 100,000 s to the end (116,790). The values taken from the spreadsheet are:

Inlet temperature average: 20.33, standard deviation 0.08

Outlet temperature average: 40.71, standard deviation 0.09

20.38 difference

I do not have spreadsheets for the other graphs.

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Yeah, I meant the delta T for each one.

If you have the spreadsheet for the 500 W, what are the average V and I values for the blower fan?

Also, why is the reactor temperature zero?

Quote from Paradigmnoia

If you have the spreadsheet for the 500 W, what are the average V and I values for the blower fan?

For the same range of rows:

Blower V: 10.57, standard deviation 0.02

Blower A: 0.48, standard deviation 0.00 (0.0042)

Quote from Paradigmnoia

Also, why is the reactor temperature zero?

The column is blank. I guess it was used in other spreadsheets.

Quote from JedRothwell

For the same range of rows:

Blower V: 10.57, standard deviation 0.02

Blower A: 0.48, standard deviation 0.00 (0.0042)

The column is blank. I guess it was used in other spreadsheets.

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Thanks

I had hoped that reactor column had a bad formula or something because it plotted something instead of a blank. Oh well.

Quote from Paradigmnoia

I did a 210 W steady to 310 W steady and almost back to 200 W steady state. 100 W delta T looks to be about 5 C which corresponds well with the below image from Jed.

I attached and sealed the 70 mm vane anemometer directly to the outlet tube with a little wider spacer-adapter and it reports almost exactly what it did yesterday, which is almost exactly 7.0 m/s. Much higher than every single data point on the hot wire traverse group which looks to average maybe 4.5 m/s. (I haven’t averaged the 33 points yet, but there are two 6.3’s (maximum T) and about a third of the points are less than half of that.)

It smells like I cooked off some input wire insulation inside the big tube on the 310 W run. It can’t really go anywhere so it should be OK. The inner cartridge was around 700 C.

.

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Paradig,

1) This shows R-19 which is the name of a Mizuno reactor. But I thought you had built your own, or did Mizuno give you R-19?

2) Did you calibrate with the same reactor as the above experimental run? Or do you (like Mizuno) have a different reactor?

3) What is different in the test reactor run compared to the calibration run? Same reactor body with an inert gas or vacuum on the inside? Same reactor body with active gas but no mesh or a non-Palladium rubbed mesh? Or different reactor body of similar external characteristics?

4) Is the reactor's H2 or D2 supply valved off from the supply system?

Assuming the control is adequate, I think this is excellent results.

P.S.

Is Paradig a good abbreviation of your Pseudo-name -- it's easier to spell for me. I hope you don't mind.

Quote from anonymous

Paradig,

1) This shows R-19 which is the name of a Mizuno reactor. But I thought you had built your own, or did Mizuno give you R-19?

2) Did you calibrate with the same reactor as the above experimental run? Or do you (like Mizuno) have a different reactor?

3) What is different in the test reactor run compared to the calibration run? Same reactor body with an inert gas or vacuum on the inside? Same reactor body with active gas but no mesh or a non-Palladium rubbed mesh? Or different reactor body of similar external characteristics?

4) Is the reactor's H2 or D2 supply valved off from the supply system?

Assuming the control is adequate, I think this is excellent results.

P.S.

Is Paradig a good abbreviation of your Pseudo-name -- it's easier to spell for me. I hope you don't mind.

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1) The R19 image was from Jed a few months ago. See the second sentence in my post. I have no active reactors. I have almost no idea how “heat converted into temperature” was performed on this plot, but presumably by a method equivalent to the Farnam interactive calculator I posted above, but solving for temperature.

2) I have a stainless steel cylinder made of stove pipe and caps that is 20 cm in diameter and 50 cm long. Inside is a ceramic and Kanthal heater cartridge that I built originally several years ago, then refit recently to install into the cylinder. The cartridge has been tested to be capable of handling 1068 W in open air. There are some cut slabs of fire bricks inside the cylinder as spacers and to increase the mass to close to that of a thick steel cylinder (and prevent it from wanting to roll off the stand).

3) I have no active reactors, the cylinder is at atmospheric pressure, and contains normal Earth atmosphere, although the high heat inside may reduce the internal gas content a bit.

4) This is Mizuno’s reactor data in the image. I have no idea.

5) call me what you want, but just don’t call me late for supper.

Here is the last test data plot. 100 W boost makes for a total delta T of 19.45 C, which is 6.7 C higher than the 200 W delta T.

The 6.7 C Delta T of the 210 to 310 W Delta T's is pretty close to my pre-test estimate, above, which was 7 C.

.

Quote from Paradigmnoia

I have almost no idea how “heat converted into temperature” was performed on this plot

Nothing to it. It is based on the calibration. That level of input should produce a 10 deg C temperature difference. It is 15 deg C instead. In other words, the blue line is actually measured; the green line is extrapolated from the input power measurement.

Quote from JedRothwell

Nothing to it. It is based on the calibration. That level of input should produce a 10 deg C temperature difference. It is 15 deg C instead. In other words, the blue line is actually measured; the green line is extrapolated from the input power measurement.

If I might be so bold, why not show a calibration Delta T instead of a calculated one?