Here is a question for anyone who wants to answer.
For an inert reactor (one with no internal heating of cooling) shouldn't one have COP = 1?
I think the answer is yes. And that it is true all the time no matter what insulation is used. Am I wrong somehow?
And don't Daniel_G's claims indicate that he believes otherwise?
Ideally, that factor should be as small as possible,.
Why? I would have thought that as long as one has a good handle on the proportion of the overall heat being captured and used drive a temperature rise somewhere, it would be sufficient to estimate total heat generation.
The calorimeter that makes the highest temperature with the least amount of heat input will give the highest COP.
According to the definition I am using, and I think others are using too, a calorimeter equipped with a control reactor (one with no exothermic or exothermic internal processes) should always have COP = 1. Does this fit with the definition you are using?
Normally known as calibration.
Daniel_G uses "calibration" for other procedures as well. For instance here
The calorimeter that makes the highest temperature with the least amount of heat input will give the highest COP.
Aha! Maybe this is why I haven't been understanding you.
I have been defining COP as total output divided by input. You appear to be calculating it as just the part of the output divided by input.
So ...take a nicely insulated calorimeter and let's say that almost all of the heat output stays inside thereby causing a rise in temperature that you can measure. You have translated almost all of the heat output into temperature change and can therefore pretty much exactly calculate COP based just on this.
Now, use the same calorimeter but take out the insulation. A much larger fraction of the overall heat output leaks across the walls than before. Now, the temperature doesn't go up so much. Calculating heat content from this temperature change only gives you part of the actual heat output from the reactor. But what you need to calculate COP, as I have been defining it, is to estimate the total output from the part you have measured. This is done by studying the properties of the calorimeter and inserting a factor into your calculations that allows for how much heat is escaping. This is what Mizuno and Rothwell do in their air flow calorimetry.
There’s so many errors in your last post I’m not going to unpack them. I have some actual experiments to run.
OK. I thought I should tell you though. Everything I said is just a consequence of having a temperature-activated heat source in a thermal mass.
I do urge you, when developing your next calorimeter, to include inside the calibration reactor a joule heater capable of delivering heat in the same sort of way you think that your active nickel mesh does. That way you can physically test out for yourself how your reactor/calorimeter should react in different circumstances and perhaps see if withdrawing some heat via a heat transfer medium will make the system independent of the normal external heaters you are using.
We use electrical power for physics experiments due to the fact that it's easy to measure. Do you follow the power of the battery/starter motor when you consider a 300HP Diesel engine?
No input power is required if your control system removes only the excess heat. Envision a system that reaches operating temperature of 600C and continues heating to 650C. A heat transfer medium leaving the reactor at 650C and returning at 600C would require input power? (hint: the answer is no) Just like we don't leave the starter motor running on a Diesel engine...
This is another area where I think you may be mistaken. Fuels, like diesel fuel, or gas, or wood, can be warmed, and might even begin to produce some "excess" heat in response. But once a threshold is passed they also go into a self-sustaining mode of combustion. Theoretically, it is the same with the sort of temperature-dependent LENR energy release you describe. There should be a low-temperature state of excess heat, but then there will be a threshold beyond which the system goes into a high-temperature state which needs radically less input energy (and in some cases maybe none at all) to sustain it. I have been calling that runaway. So far, all the data I have seen says to me that you do not have that high-temperature runaway state and instead are seeing a state of stable excess heat production. It is not in a state comparable to a Diesel engine.
This is all relevant to the system you ask me to envision. If you picture the 650C state as one of these stable, pre-runaway states that you have been displaying so far then I disagree with you. Think about the heat transfer you mention being really tiny in scale. The medium leaves at 650C and returns at 600C having given up only a tiny amount of heat energy. Do you still think that you could take away all of the input power and still have the system sustain itself at 650C? How does removing a tiny amount of heat make the system independent of outputs?
On the other hand, if you are in one of these high-temperature runaway states, then the system is already much less dependent on (or possibly free of) input energy. In that case I definitely think you could harvest some of the developed heat and the whole thing would be sustainable.
@Bruce_H, please consider dependent and independent variables in your analysis. That is what I mean about confusing math and physics.
OK. It is true that I don't understand what you are saying.
If this is new thinking arising from your work with these systems, then I suggest that when you write things up you should spend some time clearly explaining this idea because I think that others might also fail to understand.
Bruce_H, you increase COP by increasing insulation. You increase excess heat by increasing temperature or reactor size. Those two phenomenon are unrelated although the variables in the mathematical formulas are the same the formulas themselves are not the same. The two phenomena are unrelated and independent.
I begin to understand your thinking although I don't think I agree with your "unrelated and independent" assessment.
By definition, if input power and output power change in proportion, COP will be unaffected. So, for instance, if the input and output powers both double, COP remains the same.
I think that you have identified changing the amount of reactive paladium-rubbed mesh as a design criteria that capable of changing inputs and outputs in proportion. Doubling the amount of reactive mesh, for instance, would double the output power in response to twice the input power. The AXH would change (it would double) but the COP would not.
Is that right. Is that why you see them as independent?
The main point that dumbfounds me is that people think we MUST use a joule heater powered by electricity.
I dumbfounds me too. Who thinks this?
COP and excess energy are not intimately related. Period. Full stop. They are independent factors.
Maybe this is where we are having trouble. I had thought, from what you said, that COP = Output / Input and absolute excess heat (which I will call AXH) = Output - Input. For a given input power, doesn't this mean that COP = 1 + (AXH / Input)? Have I got this wrong?
I agree Para tends to be passionate about some things that I can't agree upon but Brucisms at least superficially shows some troll-like features such as lack of logic and internal inconsistencies.
From my perspective I have been logical and internally consistent. These are things I care about so if you can point out where you think I am being illogical or inconsistent then I am willing to answer.
Irregardless, I still enjoyed the exchange about the sigmoids and think his concerns were addressed sufficiently (although he may not feel the same).
Well yes and no. When you asked me to put numbers around why I expected an inflection point in the your heating curve I supplied a spreadsheet containing a simple model that embodied some of the characteristics that people claim for LENR heating. That spreadsheet was created by me in Fall 2018 for thinking about Russ George's LENR reactor. When you asked me why I proposed a sigmoidal dependence of heating on temperature I replied that, first, it seemed to be how George's reactor worked based on what I knew at the time and, second, that I thought that an ever-increasing rate of heating with increasing temperature was unphysical. I then invited you to play around with the parameters of the model to see that, indeed, the existence of inflection points in the heating or cooling curves are a feature of such systems.
I don't see anything wrong with any of this and I still stand by it. You will still get inflection points with a purely exponential dependence of heating rate on temperature. I'm not demanding a sigmoidal activation curve. That is just what I used in 2018 and what is implicit in the Arrhenius relation that Mizuno used.
I cannot follow your flip flops either. You seem to move the goal posts with every post.
No. I have been consistent but I think you are misreading what I say. I think that COP is meaningful and useful. I also think that absolute excess energy is meaningful and useful. They are intimately related because they are both calculated from the same observations.
You commented that you think that COP is meaningless because it can be altered by adding insulation to the calorimeter. But I am pointing out that that absolute excess heat would also be altered by the same thing. So I didn't understand why you wouldn't also regard it meaningless. I now understand that you want to use absolute excess power in calculations to design a scaled-up reactor and that you think that COP is not useful for this purpose. So this appears to be the reason why you think that COP is meaningless.
You can see why I was confused can't you? You said the reason COP is useless is because it can be altered by reactor configuration,. But I think you regard it as useless for a different reason.
If I want to produce a combined heat and power genset, what engineering parameter do I need to know? I need to know the absolute excess heat per cm2 (or cm3 if you like), and the efficiency of going from thermal to mechanical energy. The efficiency is related mostly to the output temperature of the reactor. So to make a 10kWe generator I will need to size my reactor to give 30-40kW of excess heat and then I need the equipment to convert that into electricity, assuming my efficiency is a conservative 25-30%. So if Mizuno's small lab reactor gives 0.3kW/cm2 at 600C, then I have all the information I need to design the CHP unit.
40,000/0.3 is 13.3m2 of catalyst surface area. Since the specific surface area is about 25cm2/cc, we would need only about 5320cm3 to get this done. This would be something smaller than a desktop computer. That's pretty cool in my mind.
When you make these design calculations for a power reactor, is it not relevant to also keep track of the input power needed to reach the operating temperature? What input power per cm2 is needed to achieve 600C ?
So can you explain in more detail why you think absolute excess heat is meaningless?
I don't think it is meaningless. I think it is meaningful. But I think that COP is meaningful too.
Thank you Bruce for finally getting my point I have been screaming out for quite some time. ERGO, COP is a meaningless number.
No. I'm afraid that I don't understand at all.
You seem to be saying that since COP can be increased by improving the insulation of the calorimeter, it is a meaningless number. But I am pointing out that absolute excess heat should increase too. So why isn't it also meaningless?
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.
If absolute excess heat is output-input, then wouldn't it depend on the insulation of the calorimeter too?
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.
In the phrase "absolute excess heat", doesn't defining some heat as being "excess" require COP to be meaningful?
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. But then they seem to say nothing about it.
A bit off-topic here, but I think it would be useful for LENR Forum to establish a thread or find a way for people to report their negative results. I suspect that a lot of sincere attempts at replication fail and then disappear. It is the file drawer problem. This creates a distorted view of a field.
... this is what you have been doing all along, casting doubt on the validity of the data because it doesn’t fit what you think it should do.
Well yes. Daniel_G (and Mizuno and Rothwell and others) portray the LENR process as one characterized by temperature-sensitive heat production. All I am saying is that if this is so then by the normal laws of heat capacitance and cooling we expect the reactor to behave in certain ways. Now I am asking if that is so.
This style of engagement is absolutely typical of scientific discourse worldwide in the academic community. I am doing nothing unusual in that regard although it seems to be greeted as weird behaviour by some here.
