ANOTHER SMOKING GUN: Maui Fire Breaks SCIENCE as we know it…
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Heat conduction. I have a background in combustion chemistry, related to jet propulsion and energy production. All the fancy references aside, you don't seem to get the point of Fourier's equation: that there must be a temperature difference between the environment and the object in order for heat to flow into the object. Once they reach the same temperature, no more heat flow. So it is not possible to impose a heat flow independently of the temperature difference. Once the object reaches the same temperature as the environment, the flow stops. This imposes the requirement that the environment must have a temperature HIGHER than the melting point of the material in order for the material to melt.
Space warping and UFOs. I would welcome evidence, but the notion of "warping space" implies some reference background by which the warping might be measured. What would that be, except space? So, I regard the subject as being intellectually ill-posed. I keep in mind that "space" is not a thing; it is a dimension. And it is nothing but measurement. As for UFOs, there has been evidence since the 1940s, all without conclusion. I don't deny the evidence; I only point out that we don't have any conclusion that it supports. What the Navy has released (I have seen it) looks very similar to aberration phenomena that can occur inside optical systems, so when they try to keep up with something, it is on the level of chasing a speck on your glasses. Plenty of misidentifications in the 60-year modern history of the phenomenon. The more convincing evidence, in my book, are the ground residue of observed landings. (J. Allen Hynek was hired by the Air Force to examine and debunk UFO sightings. He coined the famous "swamp gas" explanation. But his repeated exposure to case after case wore down his skepticism, and he eventually emerged as not exactly a proponent, but someone who took their existence as a serious possibility. I was very impressed with this intellectual trajectory. As for myself, I had a lasting lesson from the hoax by George Adamski.)
Time as a continuum. Neither. It seems self-evident that time consists of the present moment. The past no longer exists. The future does not yet exist. I liken time to a region of combustion proceeding along a slow-match: the fire is the present, the past is the ash, and the future is the uncombusted match.
Self-reference. I'm not a fan of the "Big Bang." It is an artifact of the assumption that the distance redshift is a Doppler shift. Even Edwin Hubble, the discoverer of the distance redshift, argued against that assumption, from reasons of astronomic compatibility with observation. The idea that there is no direction from which it proceeds is flim-flam, in my opinion. There is a quantum vacuum, sure enough, and it is demonstrated by the Casimir Force, which should give some pause to notions of special relativity. And the famous elevator thought experiment fails, once one is allowed to have multiple accelerometers within the elevator car. A gravity field can clearly be distinguished from a centripetal field, and from a linear acceleration without observation of the exterior universe. So, there is no "correspondence" between frame acceleration and gravity.
Thermal conductivity. The metric of conductivity is measured typically in terms of watts per (meter-kelvin). Here is an interesting summary of conductivities encountered in normal experience. https://material-properties.org/thermal-conductivity-of-materials/ Omitting the measurement units for the sake of simplicity, the conductivity of duralumin (an aluminum alloy) is 140. Steel is 50-54 or lower. rubber is 0.5, asphalt/concrete is 0.75, limestone & brick are 1.3, wood is from 0.13 to 0.17. So, while aluminum will tend to rapidly assume a uniform temperature. its ability to bleed off into the axle or onto the hard ground is very poor. And aluminum vapor combustion is ferociously hot. (Aluminum will evaporate below its boiling point, just as water will evaporate at room temperature.) The poor conductivity of the ground will require a high temperature for any heat input, and the temperature will penetrate only slightly into the ground. I have an iron stove insert and have spent decades being cautious about touching it. The fire is hotter, of course (literally orange-hot, based on the color of the coals). There is no need to lecture me on fire.
Considering that this was the crux of my argument against a tire melting a wheel, I am not sure why you seem to think I don't understand this principle.
This however is only true for direct heat transfer (conduction/convection). There are other ways to heat up an object, such as by causing the molecules to vibrate via microwaves. The environment can be 0 Kelvin and you can heat up an object by making the molecules vibrate, because when you get down to it, "heat" in an object made up of molecules is just molecular vibrational energy. If you appreciate that principle of "what heat really is," you can appreciate that my argument is completely consistent with what you think I am not understanding.
Aluminum (like all things made of molecules) will be able to absorb a total amount of energy (usually measured in Joules or BTUs) before it melts. The fact that it has a high conductivity means that it will have a relatively uniform temperature regardless of the source of input, unless that source is very concentrated (like a blow torch, in which case, see my previous explanation that I still don't think you fully appreciated). The tire will give off a certain amount of heat energy as it burns. It will almost certainly have far more heat energy stored in its hydrocarbons than is required to melt the tire (though it will have far from a complete combustion, but still, I have no doubt it is more than sufficient), but it has to get that energy into the wheel somehow. The easiest way is to heat up the local environment sufficient that the environment itself is hotter than the wheel. But except for the small part of the tire that is at the very bottom of the wheel, most of that energy is going to go somewhere else because the local environment is at about 25 C.
The heat energy (Joules e.g.) that does go into the wheel is going to leave the wheel through any contact it has (if those contacts are colder than the wheel) or through the air (if the air is colder than the wheel). WHATEVER the conductivities of the contacts are will help determine the rate of heat flow. In other words, the conductivities only set the rate of the flow, they don't change the principle of a "heat sink". With regards to the iron, it will get hotter and hotter, and because the temperature difference is important for heat transfer rate, the rate of heat flow will slow over time. Before it slows down too much though, it will likely take away quite a bit of the total Joules of energy available because there is a lot of iron, and it transfers relatively quickly in iron.. With regards to the ground however, it won't slow very much because the ground acts as a sink. Instead the heat will continue to flow into the ground at WHATEVER RATE it flows into the ground for the entire time.
Now if there is enough heat energy (lots of fuel) that isn't true, and the local ground will get hot and the transfer rate will slow or stop, but the ground is a really big environment with a reasonably fast heat transfer rate and a huge thermal capacity so the dissipation rate won't change much over the half hour or whatever it takes for a tire to burn.
Regardless, the ground will absorb a certain total amount of Joules over time and the iron will absorb a total amount of Joules over time, as will the wheel itself and the air. The fuel will transfer a certain amount of Joules to the wheel, and if the total sum of all that energy flowing in and out is ever greater than total heat capacity of the wheel, it will melt.
I've melted aluminum a few times in a kiln. I have some idea what it takes. I do not see that happening in the environment that it is in without extra help (open to air, no fire around it, only fuel is a tire and maybe gasoline that is a couple feet away burning in a completely different direction). The lack of previous melting wheels is a testament to my estimation.
You were starting out from the premise that a burning tire would be insufficient to melt an aluminum wheel. Or that it could happen even without the tire flame temperature being higher than the aluminum melting point (I have a hard time recovering this thread). I pointed out that (1) burning gasoline and/or rubber had a theoretical flame temperature adequate to melt aluminum, and (2) there was no way the aluminum could receive enough heat to melt without the higher flame temperature. So, on the whole, I don't see that we have any disagreement by now.
Microwaves would just be reflected. The same principle applies to radiative transfer. The incoming flux times the absorption coefficient would have to be high enough to be greater than the black-body radiation times the emission coefficient. But where is the evidence of any of that? The "local environment" is the flame of the burning gasoline and/or burning rubber. Made all the hotter when the combustion is occurring in a cavity where the thermal radiation is returned to the combustion. I provided the thermal conductivities. When the path is dimensionally narrow, such as an axle, the flow will be minor. When the ground has very low conductivity, the point of contact will be at the aluminum temperature, but the conductive gradient will be low and there will not be much thermal conduction to the ground in the time available to melt the aluminum. When the molten aluminum spread out thinly enough, it covered enough area for the surface conduction (and evaporation) to bring it below the melting point. I mean, I did this for a living. Your arm-waving is only that.
I've seen aluminum melt in a gas-fired forge about half the size of a suitcase. Pretty fast. No need for a kiln. All that is required is to be surrounded by the flame. It doesn't occur to you that the auto fuel tank probably lost its integrity by the initial fire, sprang a leak, lit off, and continued leaking gasoline onto the ground underneath the car, where it burns and ignites the tires. The tires surround the wheels. Burning rubber is no slight matter, as demonstrated by the "necklacing" committed by terrorists in South Africa. One tire, a bit of petrol, and a match, and the poor victim is rendered like a side of pork. Yes, the rubber can burn...and it can burn at a high enough temperature to melt the aluminum. You can hardly say that the wheel is somehow distant from the tire.
You are missing what I keep saying. The melting of aluminum by microwaves is not a function of the cross section of the microwaves with the aluminum lattice, but with the free electrons on the boundaries. The reflections, if directed towards other boundaries, increase this interaction, thus the more boundaries in a close area the more interaction between photon and free electron -> stronger electric field -> plasma -> melting metal (or heating metal). This happens with any material with free electrons. I couldn't find the original tech that I was thinking of that shows this, but I did find one. It's not a good explanation, since it's a popular science release, not a technical one, but it gives an idea of how this can be accomplished in a 3D printing technology.
If there is a discontinuous surface (a rough spot, or dent with pits e.g.) then there will be a lot of reflections in a localized area, and a lot of free electron movement. This will lead to a plasma that will melt the metal which will cause even more discontinuity in the surface (of say an aluminum wheel), which will lead to more reflections, etc. This is a runaway thermal effect, which can lead to the complete destruction of some metal object in a microwave field.
Having said that, the incoming radiation would have to be high enough and last for long enough to make it happen. So is that feasible? I don't know. It would have to be modelled, and I'm not doing that. The point is, technically it is possible. Admitting it is possible is an important step in any investigation, and usually the biggest hurdle.
This is the best argument you have made. Don't get me wrong, your objections are reasonable. You have made good arguments, though in some cases, like above, you keep sidestepping the statements I am making. But when it comes down to it, if I don't put my math where my mouth is, it's just that; arm-waving.
My purpose was not to make you believe it to be true. I don't believe it to be true. I do however believe that it is possible, and you do not. My point was only to get you to admit that it was possible. You keep sidestepping the first and most important point I made by arguing completely different topics.
If you look at all of the evidence from all of the "really big uncontrollable urban fires" from the past 6 or 7 years or so, you find one thing that keeps coming up. The things that have metal in them are burning completely, and the things that do not are fine. For example, grass, trees, fences sometimes, etc. are still standing and green and/or not even singed, but buildings, cars, lamp posts, etc. are completely destroyed. Fire is spreading across hundreds of yards of fire breaks without apparent reason. It is plausible that it is spread by "high winds," but it is also possible that is not the reason it is making it across those gaps at all. There are numerous reports of Firemen who are flabbergasted by the behavior and results of the fires. They insist "they don't make any sense". Cars are completely melted next to trees that are green. Houses are burnt to dust while still sitting under the green branches of their trees. Not just once or twice, but everywhere. This is not the behavior seen in fires prior to a few years ago.
Something has changed.
All you have to do to figure this out is look. You refuse to do that, because it's "impossible." Thus my desire to convince you it's not impossible. It is impossible to convince you if you don't address the actual argument I am presenting.
You are an example of someone who seems experience-free. I worked on DEWs for decades, with the objective of melting through aluminum fuselages. It does not require recondite theories of how metal is heated. The fact of the matter is that even shiny aluminum is not perfectly reflective, so you simply have to provide enough intensity on target that you manage to get about 4 watts/cm2 absorbed by the target. The rest is ineluctable. But aluminum is a lot more shiny when incided by microwaves, so the overall power requirement is higher.
As for fire, you have no appreciation of wild fires, which are notorious for freaks of combustion resulting from the fact that the "fire" is a 3-dimensional volume of space that is being twisted and convected by its own physics. This is not only "plausible," it is a fact of life. We have forest fires in the Pacific Northwest, and big ones at that, though we don't get on the national news all the time. Do you have any idea what it means when a forest has been soaking in hot summer days, exuding isoprene? It makes the very air semi-flammable. I took a drive into the mountains one summer day and stopped at a stream crossing to stretch my legs. Trees all around (conifers). When I stepped out of the car, it was like I had stuck my head in a bucket of turpentine. Absolutely no mystery why there are red flag fire warning days.
No, I don't think anything has changed. It is more a matter of the uneducated looking at something for the first time and being amazed.