In particular, I commented on the difficulty of long-duration testing with adiabatic calorimetry, and I stand by that comment.
Alan, why would long-duration testing be difficult? Could you please elaborate? What exactly is long-duration and why would adiabatic calorimetry be problematic?
And for true adiabatic ("bomb") testing, a double-wall structure is really needed, with either vacuum or good temperature control of the inter-wall cavity.
Please see my previous post about the adaptation of adiabatic calorimetry concept we use. The walls are not temperature controlled. It's basically an insulated convection oven with an internal mixing fan and multiple TC for temperature monitoring. Calibrations are easy. Set the power input, and wait for a new equilibrium temperature to be reached. You can place anything you want into the calorimeter and the only change is the time to reach equilibrium. The final temperature doesn't change.
Please see my previous post about the adaptation of adiabatic calorimetry concept we use. The walls are not temperature controlled. It's basically an insulated convection oven with an internal mixing fan and multiple TC for temperature monitoring. Calibrations are easy. Set the power input, and wait for a new equilibrium temperature to be reached. You can place anything you want into the calorimeter and the only change is the time to reach equilibrium. The final temperature doesn't change.
All Mizuno's published tests used internal heating, and there was a suggestion at one time that heat radiated from the internal heater out to the meshes and then exiting through the walls of the reactor was an important factor.
Reading your post above, have you now given up on internal heaters and switched over to external heat from your convection oven?
Notice nobody uses IR cameras for LENR claims anymore. Not because it doesn’t work, but because as soon as someone does, they figure out the Lugano problem for themselves.
What problem is that? Can you explain briefly?
All Mizuno's published tests used internal heating, and there was a suggestion at one time that heat radiated from the internal heater out to the meshes and then exiting through the walls of the reactor was an important factor.
He used external heating in some early tests, but all of the highly successful tests were with internal heating. It may be that all the published results are with internal heating; I don't recall.
You know, I respect and admire greatly the opinion of magicsound because he invested considerable time and effort on making a replication of a Mizuno analogue system and he found no trace of excess heat.
I do not think he had the tools to examine the materials in detail. No one seems to have them. Some people said they did, but I never heard back from them, which is disappointing. The materials are the key to cold fusion. If you cannot examine them in detail, with SEM and other tools, you are flailing around in the dark.
One might conclude that crucial information has been withheld by Mizuno, among other things.
Nope. It has to be the materials. Many of Mizuno's own tests fail, even using exactly the same calorimeter and procedures.
What problem is that? Can you explain briefly?
The emissivity problem.
The Optris IR camera emissivity setting for Lugano was set to the Total Hemispherical Emissivity (for the entire IR band), not the emissivity of the In-band Spectral sensitivity range of the camera (6.5 to 13.5 um), which is about 0.95 . Worse, the Hemispherical Emissivity was modified by a silly re-iterative method which further distorts the temperatures reported by the Optris IR camera. The Total Hemispherical Emissivity used in Lugano at high temperatures was about 0.42. The error greatly inflates the reported temperature, resulting in a huge calculation error for the radiant and convective heat. The error in the Lugano report exactly accounts for the reported excess heat, within measurement uncertainties.
The Total emissivity is correct to be used for calculation of the output heat.
The In-band emissivity is correct to be used for the cameras setting.
The Total emissivity is not to be used for the camera setting.
The In-band emissivity is not to be used for the heat calculation.
The re-iterative emissivity method used in the paper is a completely fabricated nonsense.
I do not think he had the tools to examine the materials in detail. No one seems to have them. Some people said they did, but I never heard back from them, which is disappointing. The materials are the key to cold fusion. If you cannot examine them in detail, with SEM and other tools, you are flailing around in the dark.
Nope. It has to be the materials. Many of Mizuno's own tests fail, even using exactly the same calorimeter and procedures.
I think magicsound is one of the few independent replicators that did indeed look at the material with his SEM. He even found cubic calcium carbonate crystals after the process of washing the mesh. Had he been sent a working mesh by Mizuno, we would know undoubtely a lot more of what made a Mesh work,
He used external heating in some early tests, but all of the highly successful tests were with internal heating. It may be that all the published results are with internal heating; I don't recall.
Sorry Jed, I was just thinking of the current tech using Ni mesh. As you say earlier iterations did use in at least one case external heat.
This is simply wrong. There were replications that did report excess heat so this hypothesis is falsified.
You are a joke. Mizuno was talking about COP 10 not COP 1.1 .. 1.3...
Had he been sent a working mesh by Mizuno, we would know undoubtely a lot more of what made a Mesh work,
Had he asked for one, we would have sent it. Unfortunately, even when we sent samples of meshes that worked for Mizuno, they did not work for the people we sent them to. We concluded that they may have been contaminated along the way.
Mizuno might still have some, so he should ask.
Sorry Jed, I was just thinking of the current tech using Ni mesh. As you say earlier iterations did use in at least one case external heat.
I recall that even the nickel mesh had an external heater in the gigantic first cell. It was a long strap with a resistance heater, wrapped around the outside of the cell. However, the cell produced little anomalous heat and I don't recall he even published the results. He might have referred to them in some publications.
It is not a good configuration. Moving the heater inside made a big difference.
Alan, why would long-duration testing be difficult? Could you please elaborate? What exactly is long-duration and why would adiabatic calorimetry be problematic?
In true adiabatic calorimetry, no heat is transferred to the surrounding environment. Energy is calculated from temperature rise of the enclosed volume of known mass. In laboratory practice, such measurement is usually done in a vacuum dewar chamber or similar vessel, where heat transfer by convection and radiation are reduced to insignificant levels. Therefore, with a constant source of heat the internal temperature will continually increase until changes in material and reactions cause some failure. In other embodiments, the device under test would be immersed in a large well-insulated container of water or other liquid. The heat rise of the enclosing liquid allows easy calculation of the energy added to the system by the device under test. Such a system is sometimes referred to as a "bomb calorimeter" perhaps due to the physical appearance of the enclosure. The long duration limit is determined by phase change of the liquid used.
In the case of your oven-based system, heat is allowed to escape from the oven itself. The energy calculation could be done by measuring the power needed by the oven heater to maintain a set temperature. That is not adiabatic calorimetry, but rather isothermal. However, if I understand correctly, you do not change the power input to the oven, but rather measure the difference between the calibrated oven temperature at a set power and the equilibrium temperature with the reactor operating and the oven power unchanged. If the reactor has an internal heat source, the temperatures inside and outside of it will rise, but at different rates due to the complex thermal mass and heat transport environment. In such a system, time to equilibrium would be long, possibly days rather than hours. If the reaction is temperature-related and also time-limited as has been reported, extraction of accurate data with such a calorimeter seems unlikely.
Finally, I want to point out that my own system of measurement also depends on heat transport through the wall of the reactor. The external environment (still air in the lab) is nearly isothermal, and the ambient temperature is measured and known to vary within ±2°C during the tests. The advantage of this kind of measurement is low thermal inertia, with equilibrium time typically of 1 hour or less.
In true adiabatic calorimetry, no heat is transferred to the surrounding environment. Energy is calculated from temperature rise of the enclosed volume of known mass. In laboratory practice, such measurement is usually done in a vacuum dewar chamber or similar vessel, where heat transfer by convection and radiation are reduced to insignificant levels.
Correctamudo. I was going to say that in response to Daniel_G but you said it first. And you said it better. Let's hear it from Hemminger & Hohne, p. 85
"Adiabatic Operation
Calorimeters can also be operated in an adiabatic manner. In this case, under ideal circumstances, no heat exchange whatsoever occurs between
measuring system and surroundings. There are three ways of meeting this requirement as satisfactorily as possible.
1. The sample reaction takes place so rapidly that no appreciable quantity of heat can leave or enter during the measuring interval.
2. The measuring system is separated from the surroundings by an "infinitely large" thermal resistance, i.e. thermally insulated in the best possible way.
3. The temperature of the surroundings is so controlled as to be always equal to that of the measuring system . . ."
As you see, this situation can only continue for a short time. Say you have a liter of water as the heat sink. It goes from 20 to 30 deg C without radiating much heat. Above that it starts to lose heat and pretty soon you have an isoperibolic calorimeter, not an adiabatic one. As noted, I think adiabatic calorimetry is mainly used for bomb calorimeters, where the reaction happens in flash (or kaboom!) and the heat sink temperature rises more gradually after that. I do not think the name "bomb calorimeter" was due to the physical appearance of the enclosure. I think it is because they tend to explode. They are, in fact, bombs. They used to be used to test small samples of explosives.
Finally, I want to point out that my own system of measurement also depends on heat transport through the wall of the reactor.
That's isoperibolic operation. H&H describe the three major types of calorimetry on p. 83. I quoted them here, on p. 8 and 9, with some explanations added by me:
https://www.lenr-canr.org/acrobat/RothwellJreviewofth.pdf
The text begins:
"The term 'isoperibol' operation refers to the use of a calorimeter at constant temperature surroundings with a possibly different temperature of the measuring system. The thermal resistance Rth between the measuring system and the surroundings is infinitesimally small in isothermal calorimeters, of finite magnitude in isoperibol calorimeters . . . and infinitely large in adiabatic ones . . ." etc.
I do not think the name "bomb calorimeter" was due to the physical appearance of the enclosure. I think it is because they tend to explode. They are, in fact, bombs.
Yes, you are quite right. I used to use one for testing the calorific value of powdered coal samples. That particular bomb test involved putting 25 grams of coal dust inside, clamping the lid on and then topping it up with 4 bar of pure oxygen before pressing the igniter button. The temperature rise (and the internal pressure rise) was pretty spectacular. It was linked to an old-style chart recorder so I used to hit the button and go for a smoke in the car park.
That's isoperibolic operation
Thanks for the correction Jed. As you know, the thermal conductivity of stainless steel is pretty low, so the heat flow out of my reactor is reduced, though not infinitesimal of course. Therefore, in my testing I measure both the external skin temperature and the internal temperature (in a thermowell). The result is somewhere between isothermal and isoperibolic measurement. The high thermal conductivity of hydrogen gas results in the thermowell temperature being closer to that of the Ni mesh than the reactor external temp.
Our current system of calorimetry is an adaptation of adiabatic that is simple, works very well and can work for very long periods of days, weeks and months.
Instead of being bogged down in textbook nomenclature you Can find the description of the system in this thread and comment and criticize as you feel.
I think Magicsound was very well equipped. The type of calorimeter used has no prior experience in measuring lenr reactors successfully. I don’t think it will work but that’s just my opinion. A known working reactor could tell if it’s a calorimeter issue or a reactor issue. The type of calorimeter matters.
If we are going to coin a term for our method of calorimetry perhaps pseudo adiabatic would be a more reasonable term. It works very well and is very simple with much fewer issues relative to air flow.
As for his replication attempt, I think many small details were not done exactly as the original publication. Jed has more details than myself in this regards. He is the one better equipped to comment or guide as I have moved in a different direction since becoming involved.
MTI’s current technology has moved on since this publication but IP concerns prevents me from saying any details. We feel the best compromise is sending working reactors to competent validators who then can test it their own calorimeters based on the principles outlined earlier in this thread.
If we can all agree that COP would depend on insulation of the calorimeter then it also follows that COPs are meaningless. Some people still are not serious about understanding the gravity of this statement. Absolute excess heat is the only parameter that matters.
Thanks for the correction Jed.
It is not a correction of you. I am just saying what H&H call this method.
As you know, the thermal conductivity of stainless steel is pretty low, so the heat flow out of my reactor is reduced, though not infinitesimal of course. Therefore, in my testing I measure both the external skin temperature and the internal temperature (in a thermowell).
As soon as it stops heating and it reaches a stable temperature, that's isoperibolic. During the time it is heating up and not radiating much, that's adiabatic. In other words, it is both, during different phases. First adiabatic, then isoperibolic. You should compute the heat with both methods. They should agree. It is a good cross-check.
Our current system of calorimetry is an adaptation of adiabatic that is simple, works very well and can work for very long periods of days, weeks and months.
That's not possible! The device would get hotter and hotter, until it vaporized. Adiabatic means no heat leaks out.
Instead of being bogged down in textbook nomenclature you Can find the description of the system in this thread and comment and criticize as you feel.
"Textbook nomenclature" is a strange way to put it. Would you say that confusing amperage and voltage doesn't matter? Or temperature and heat? Are those merely a matter of terminology? Adiabatic calorimetry that lasts for weeks would end up with a cell being hotter than the core of sun. It is impossible. You must be confused about the type of calorimetry you are doing. Since you don't even know what method it is, it is difficult to have confidence in your description.
Thanks Jed. The type of calorimetry used is not strictly adiabatic, isoperibolic nor is it a bomb calorimetry. It’s an adaptation optimized for measuring lenr reactor excess heat. That is why I said the more appropriate term would be pseudo adiabatic.
Anyone is welcome to take a look at the detailed methods and comment or criticize.
