Mizuno reports increased excess heat

  • Have you verified that the hotwire anemometer is not recommended for turbulent systems.?

    You need to show calculation of why not rather than a ROT.. based on turbulent intensity.

    What do you recommend... a pitot tube?

    Wkiipedia

    ""Hot-wire anemometers, while extremely delicate, have extremely high frequency-response and fine spatial resolution compared to other measurement methods, and as such are almost universally employed for the detailed study of turbulent flows, or any flow in which rapid velocity fluctuations are of interest.""



    RB: that is not inconsistent with AF's point. The issue being that turbulent flow can register in all directions, and the velocity magnitude is recorded. Whereas the actual velocity, averaged, is needed. Worst case you get rectification of reverse flow and therefore overestimation of average velocity.


    In addition the anenometer will not measure the velocity component in the forward direction alone, so sideways movement will be counted when this does not actually lead to greater airflow.


    No idea how large this effect will be, but AF has a point. That is why exact controls are helpful: they would deal with any issue to do with poor airflow measurement.

  • Have you verified that the hotwire anemometer is not recommended for turbulent systems.?

    You need to show calculation of why not rather than a ROT.. based on turbulent intensity.

    What do you recommend... a pitot tube?

    Wkiipedia

    ""Hot-wire anemometers, while extremely delicate, have extremely high frequency-response and fine spatial resolution compared to other measurement methods, and as such are almost universally employed for the detailed study of turbulent flows, or any flow in which rapid velocity fluctuations are of interest.""



    I raise a concern. I am not an expert. I have no recommendations, except that the Google Calorimetry team has the resources to do this and should be urged to do so.

    In my opinion : Hot Wire Anemometers (and Infrared Thermometers ... remember Lugano, etc) are excellent for showing DIFFERENCES of values in space and time. But they are not so good for measuring absolute, qualitative values.

    I defer to that detailed lab discussion, and to the warnings by several manufacturers NOT to use hot wire anemometers in turbulent flows.

  • I do not have time to review these graphs, or understand them in detail. I won't have time until after the conference. But anyway, you need to do a traverse test, and it has to come out similar to Fig. 4 in the paper. If the points from 7 or more locations are not right on top of one another, the air is not mixed enough, and the temperature is not uniform enough. That is the proof of the pudding. If the points are all on top of one anther, and you do an extra 7 measurements and they are smack on top of the first 7, you are good to go. The instrument is working.


    You mentioned something about the air flow being stronger toward the edge of the pipe. That's not good. That is not working.

  • the warnings by several manufacturers NOT to use hot wire anemometers in turbulent flows.

    This is strange.


    sources please and exact words..


    almost all traverses today are done today with hotwire anemometers rather than pitot tubes/ultrasonic meters

    much of these are in turbulent flows.. since laminar flows result with lower velocities in large pipes which are

    more costly to build than smaller pipes


    The idea of turbulence intensity is very different from that of turbulent flow..

    probably it is high in unsteady flows which are what one might get in the disturbed region near the fan blades

    Mizuno's traverses are some way away from the fan blades where the turbulent flow has a steady profile.

  • I have this uncomfortable feeling we are still splitting hairs when the claim is 250W output power with a 5:1 output/input ratio. You don't need a whole hell of a lot of accuracy to measure that. And then not to forget: calibrations with Joule heat are right on.


    SOT - sorry to say I told you so, but...


    A one-off result, not carefully tested, on new equipment, is not a claim. And R20 has now been dismantled (which I do find extraordinary) so no more such results, and no more testing.


    My consistent comment on R20: "It would be unfair to Mizuno to take what he states is a preliminary sample result as anything definite".


    I stand by it, and think events now bear this comment out.


    I don't count anecdotal comments about room heating, but if I did I would have to ask what is the efficiency of that 100V variable output PSU supplying the heater. The total dissipated heat in the room would be that from the R20, + that from the PSU! We do not know much about the PSU...

  • RB:

    almost all traverses today are done today with hotwire anemometers rather than pitot tubes/ultrasonic meters

    musch of these are in turbulent flows.. since laminar flows result in large pipes which are

    more costly ot build than smaller pipes


    Sources and details, please. How often are the (high frequency) outputs of the anenometers averaged to determine overall cross-sectional airflow when such measurements are made? What are the expected errors? I have no idea myself, and if you do, then these details would help.


    THH


  • OK, let me be clearer:


    "A one-off result - not carefully documented". Of course I can only go by what was written up in the paper.

  • I have this uncomfortable feeling we are still splitting hairs when the claim is 250W output power with a 5:1 output/input ratio.

    Well, splitting hairs is what geeks do. It is okay as long as you acknowledge that's what you are doing. Anyway, the R20 with the new mesh is nowhere near as good as 250 W. Maybe it will improve. The 5:1 ratio is meaningless and should be ignored.


    And then not to forget: calibrations with Joule heat are right on.

    That they are. Calibrations are the only way to be sure the calorimetry is working. What I find odd is how so-called skeptics are not satisfied with calibrations, no matter how many we do. They do not come back and say, "why don't you try calibration method A or B?" They just say this isn't enough, or they say nothing.

  • Sources and details, please

    First we clarify what sources ALAN Fletcher has which say


    "the warnings by several manufacturers NOT to use hot wire anemometers in turbulent flows.""


    because this is where most anemometers are being used for traverses... in commercial pipes in turbulent flows

    There is a difference between a steady and an unsteady turbulent flow.

    This is my experience


    If THHhuxley can find and clarify.. definitely what AF means by this... that would be great

  • Of course I can only go by what was written up in the paper


    No THHhuxley always adds in just a whole lot bit more..of unknowledge


    such as 64% error in the anemometer readings...

    then it comes down to educating him about

    about basic physics.. such as the correct numbers... formulas.. laws.

    which results in" 64 pages or so of weird"" as he says

  • [The 5:1 ratio is meaningless and should be ignored]


    With that attitude, we will still be here when the cows come home.

    You do not seem to understand that the ratio is entirely arbitrary. We can set it to any number we like, just by changing the insulation. It is convenient to have input be a fairly large ratio of output because that makes it easy to cool the reactor and quench the reaction. We could make the ratio 1:100 today, but there would be no simple way to turn the reaction off. Plus it would take hours for calorimeter to settle, so we would only see the power level as it was hours ago.


    With a practical heat engine you would use heavy insulation and make the input ~100 times smaller than output. The heat would only leave by phase change (steam), or conversion to mechanical energy, or with a radiator. You don't want those things in a calorimeter.

  • The COP is only one of a number of factors which Mizuno is working on 24/7 right now... I guess.

    He is not working on it all as far as I know. It is, as I said, arbitrary, and it can be set to any number you like by insulating the cell. But making it high would make the experiment difficult, with gigantic latency, and possibly even dangerous.


    Insulating the cell might clobber the reaction, if heat flux is needed.


    It is also possible the heater IR is promoting the reaction. If that turns out to be the case, the IR can be increased without increasing the rest of the input power.


    He is trying to increase the absolute level of output. The input power to the resister has nothing to do with that. You need enough power to bring the temperature up to operating temperature of the reaction. That's why it is taking 100 W to produce 30 W excess now, but only 50 W were needed to produce 250 W excess. That was self-heating.

  • My consistent comment on R20: "It would be unfair to Mizuno to take what he states is a preliminary sample result as anything definite".


    I can't let this one pass unchallenged. Mizuno/Rothwell didn't call it preliminary. And you are twisting the meaning of "sample." Mizuno/Rothwell/paper clearly states: "This section describes a typical result with the latest and most effective reactor, version R20." They are not using the word sample to mean a "one-off result." To the contrary, they are using the word sample to mean a "typical result."


    Quote

    I stand by it, and think events now bear this comment out.


    Go ahead and stand by it, but it is a misconstruction of what was said in the paper. And the events are just getting underway. You have the "quick-to-dismiss" disorder that has so engulfed the scientific establishment since P&F.

  • Quote

    You do not seem to understand that the ratio is entirely arbitrary. We can set it to any number we like, just by changing the insulation. It is convenient to have input be a fairly large ratio of output because that makes it easy to cool the reactor and quench the reaction. We could make the ratio 1:100 today, but there would be no simple way to turn the reaction off. Plus it would take hours for calorimeter to settle, so we would only see the power level as it was hours ago.

    I do see that. In fact, I've often noted here in the past that any reactor that makes substantially more heat than it requires can be made self running with enough insulation and by sending the output heat back to the reactor. And yes, it could be dangerous (but don't tell that to robert bryant .


    But the point is, you are not trying to measure an output of 101 Watts while putting in 100 Watts which is how too many experiments have been reported and judged to be positive. You need an impressive output/input ratio to be reasonably sure that your signal is substantially over any possible noise, ground loops, induced EMF, and other errors and problems. Of course, good calibration also helps.


    ETA: Of course, if you used a liquid cooled, temperature-controlled, forced flow calorimeter like SGVIT demonstrated, you would have better control of the experiment's temperature and better safety. But I do understand that such a system is much more complicated to build and control and if the air calorimeter works, you wouldn't want it.