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Post by Andrew on Feb 24, 2012 19:26:14 GMT
1. The air gap is too small by an extreme amount. There is a reason why double glazing units have those one cm spacings. They must be optimised for reduced convection for very small spacing versus increasing conduction for smaller air gaps.
2. Having a block of metal that size at room temperature is a heat sink that means it will take a while for that block of metal to reach an equilibrium temperature with the surroundings when heated by the preheated block
i. The block has to be able to emit radiation to the hotter surface, which it can do
ii. The block must not be causing an effect where a greater heat loss is created for the hot block other than that caused by radiation.
iii Obviously if the blocks are in contact that hot block plunges in temperature that side. Having the blocks at an extremely close distance is different to having them significantly further apart.
3. You are not performing the experiment as i am expecting it to be done. I have mentioned this now about 4 times at least.
4. Spencer had a heated block. You must have blocks in equilibrium or close to it before they cool. It would be better to preheat both blocks so that you have a hot block a warm block and room temperature.
5. The unheated block acts as an insulator. No insulator is very effective until the mass of insulation has established a temperature gradient thru it. The insulator has to become warm.
The significant part of this is the same as said before though. The block must not remove more heat than radiation does alone to the point it means no radiation results are observeable.
I am at a total loss to understand why you have placed them so close together.
And please stop the stuff about me back tracking. I am not.
Spencers proposed set up used a vacuum and a heater. I arranged my tests so that conduction/convection would not in my opinion have a big influence.
Also a radiation thermometer measures the relative heat content of the absolute top part of the surface and is more sensitive to the set up i used where there was a moveable mid range plate, and the thermometer and the surface measured were fixed in place.
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Post by Andrew on Feb 24, 2012 20:08:17 GMT
1. I think though, you have fundamentally misunderstood the experiment you have to construct or what you are looking for? 2. You said: Iceskater said the warmer part would be warmed further by the colder part during the cooling processWhat I said or at least was doing my best to convey when it is not so easy to put into words was: When the warm object 1, is cooling, 1 will be warmer on the surface where it is near a cooler object 2 , where otherwise/elsewhere, 1 will be exposed to the fewer emissions coming from a very much colder surface 3. So three surfaces were involved of 1 = Warm, 2 = cooler and 3 = very cold. Your arrangement does satisfy that condition [size=2]once[/size][/color] the room temperature block has warmed up. So no problem apart from what you might expect to see from this experiment. 3. However, you have a tiny air gap of 0.25mm Why did you chose such a tiny air gap? Also since you are not doing this in a vacuum and convection/conduction of air are present it might be better to reduce the temperatures rather than have them so relatively higher than the environment, otherwise between the two blocks you will have a greater convective current. [/quote] Only two matter in this discussion; the two Fluke bead probes at the gap and outer edge. It is at the gap you have insisted would get warmer than the exposed face. Are you changing your story now? So, rather than introducing all sorts of new added caveats, let's stick with what you originally argued. This doesn't need to be any more complicated than what I've already done. [/quote] Magellan This is an experiment. It has to be as complicated as necessary in order to test what you are testing for. There are no new caveats being introduced by meFor the experiment to work it has to be done correctly. With your set up that begins without equilibrium of the hot and cold block and the surroundings, until you can demonstrate that equilibrium has been achieved ,you are doing something very different to what Spencer proposed, where he would just wait for the other block to be in equilibrium no matter how long it takes. I am going to ask you again, do you understand what you are supposed to be demonstrating? Why did you say this? Iceskater said the warmer part would be warmed further by the colder part during the cooling processAnd why when i have objected to your interpretation are you saying
Only two [temperatures] matter in this discussion; the two Fluke bead probes at the gap and outer edge. It is at the gap you have insisted would get warmer than the exposed face. Are you changing your story now?
So, rather than introducing all sorts of new added caveats, let's stick with what you originally argued.
This doesn't need to be any more complicated than what I've already done. I am not changing anything at all. Either do this properly or dont bother at all. I have clear objections to your method If you are right you will be famous. If I am right my life is not going to change.
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Post by icefisher on Feb 24, 2012 22:09:39 GMT
Magellan says:
Only two [temperatures] matter in this discussion; the two Fluke bead probes at the gap and outer edge. It is at the gap you have insisted would get warmer than the exposed face. Are you changing your story now?
Iceskater: Either do this properly or dont bother at all.
What do you want him to do, heat the gap for you? Fake the experiment? The gap is not warmer and you can't claim the object was too distant. Conduction does not matter its just electromagnetic energy also. It doesn't run backwards either.
All you are doing here is slicing the salami ever thinner to avoid admitting you are wrong.
Magellan told you the IR thermometer is the problem with your kitchen experiment.
A medical IR thermometer is adjusted to take skin temperatures only. IR thermometers work terrible on anything they are not explicitly built for. Further, metals are a big problem because emissivity is so adjustable on metals by polishing, by alloy, and by oxidation.
Upgraded IR thermometers let you adjust for emissivity and provide look up tables for common materials; but these look up tables cannot tell you how much polish or oxidation, or even usually even what the alloy you might have in your hand.
Thus what you want to try to do with an IR instrument has to be done in a lab where all the variables can be strictly controlled. Further what you block the hole in the freezer with, if using a IR measuring device, needs to have the same emissivity as the hole. The hole may not be blackbody equivalent but its going to need a product to block the hole that is darned near blackbody.
IR thermometers are low resolution compared to visible light sensor because of the low energy of IR. So they have far poorer accuracy to begin with before you get into the reflectivity issues. Further you cannot use an IR thermometer to measure a surface looking at a black hole then put a piece of metal up that will reflect light. The IR will pick up the change in reflections and give you a spurious warming signal.
If you are going to use black boxes or models to convince yourself of global warming, you better be sure you understand what goes on inside as advised by Lord Kelvin.
I was a luke warmer until the G&T paper. And it wasn't the G&T paper that convinced me otherwise to a completely neutral position on backradiation. What convinced me was how an RC climate scientist set up a blog to refute G&T. Then a few dozen invited scientists participated. They ended up arguing about how backradiation "nets" between themselves.
Thats when I knew no experiment had been done.
Here we have an alleged visible death ray more than half the world scientists seem to believe is likely going to destroy the world if we don't take drastic steps. And not one of them can complete an experiment using the best laboratories and best equipment in the world.
And they know that needs to be done as they demanded it from Svensmark. Svensmark delivered and climate science is still milling around trying to figure out how to prove their magic death ray.
The fact they have not done that undoubtedly means they can't do that and its not being done here either. . . .or in your kitchen Iceskater! Magellan already knew that he is just being nice to humor you and try to teach you something.
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Post by magellan on Feb 24, 2012 22:37:07 GMT
Increasing the distance between the parts would have slowed the rate of cooling of the hotter object. Darn, my trick has been exposed.
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Post by Andrew on Feb 24, 2012 22:43:28 GMT
Conduction does not matter its just electromagnetic energy also. Conduction is the transmission of the energy consisting of atomic kinetic vibrational movement, where such movement is called heat, thru a material. Electromagnetic energy is a different energy. double glazing units have a greater than 12mm spacing for a good reason In air spaces smaller than 12 mm, heat conduction increases rapidlyMagellan and you, can either learn or not learn.
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Post by magellan on Feb 24, 2012 22:45:23 GMT
Conduction does not matter its just electromagnetic energy also. Conduction is the transmission of the energy consisting of atomic kinetic vibrational movement, where such movement is called heat, thru a material. Electromagnetic energy is a different energy. double glazing units have a greater than 12mm spacing for a good reason In air spaces smaller than 12 mm, heat conduction increases rapidlyMagellan and you, can either learn or not learn. 12mm it is then Iceskater!
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Post by Andrew on Feb 24, 2012 23:11:41 GMT
Increasing the distance between the parts would have slowed the rate of cooling of the hotter object. Darn, my trick has been exposed. Magellan You were supposed to be doing a radiation experiment. There are advantages to doing this experiment in a vacuum but the set up may yet work with some changes. i, it was unreasonable to put the metal so close together because of conductivity in air issues. ii, the two blocks should be so heated that when cooling they are already close to their equilibrium temperatures. The warmer colder block then sends more radiation to the hotter block than is received from the room temperature surroundings. iii, the unheated room temperature block cannot send more radiation to the heated block unless the cold block begins warming. But it is metal and removes heat from the heated surface very quickly. 1. Please repeat this experiment with the faces 10cm apart. 2. Heat the two pieces in the oven as before to 150. Or better have two ovens. one at 150 and the other at 130 3. If you only have one oven, remove one piece only, insert a thermocouple and wrap it in insulation foil and rock wool. Leave it till it is 130 on the outside surface. 4. Place the metal 10 cm apart and measure the outer faces and inner faces of both. I am going to do something similar here in Finland. If you can prove me wrong then you have demolished a significant amount of heating claimed to be due to the green house theory. So it is worth the effort to demonstrate it in a manner that other people will be convinced by. Currently your method has at least two major issues. And for sure unless you prove failure in a vacuum you will not get credibility. However if should work with changes so if it does not you could be famous.
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Post by magellan on Feb 24, 2012 23:31:31 GMT
Increasing the distance between the parts would have slowed the rate of cooling of the hotter object. Darn, my trick has been exposed. Magellan You were supposed to be doing a radiation experiment. There are advantages to doing this experiment in a vacuum but the set up may yet work with some changes. i, it was unreasonable to put the metal so close together because of conductivity in air issues. ii, the two blocks should be so heated that when cooling they are already close to their equilibrium temperatures. The warmer colder block then sends more radiation to the hotter block than is received from the room temperature surroundings. iii, the unheated room temperature block cannot send more radiation to the heated block unless the cold block begins warming. But it is metal and removes heat from the heated surface very quickly. 1. Please repeat this experiment with the faces 10cm apart. 2. Heat the two pieces in the oven as before to 150. Or better have two ovens. one at 150 and the other at 130 3. If you only have one oven, remove one piece only, insert a thermocouple and wrap it in insulation foil and rock wool. Leave it till it is 130 on the outside surface. 4. Place the metal 10cm apart and measure the outer faces and inner faces of both. I am going to do something similar here in Finland. If you can prove me wrong then you have demolished the green house theory. So it is worth the effort to demonstrate it in a manner that other people will be convinced by. Currently your method has at least two major issues. And for sure unless you prove failure in a vacuum you will not get credibility. However if should work with changes so if it does not you could be famous. Of course there was nothing wrong with your mickey mouse setup I don't see the need to measure the temperature of the colder object. It will warm, QED. I am only interested in observing a slower rate of cooling of the hotter object as you have stated will occur due to back radiation. No skin off my back if I'm wrong. In fact, I asked for radiative transfer equations in hopes of discovering why my observations did not follow what you predicted. BTW, have you bothered to check what the specific heat content and thermal conductivity of air is? There will come a point if you want to discriminate temperature differentials too low where only a climate controlled lab environment using very, very expensive thermometers can be reliable. At that point I'm done with this thread completely.
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Post by Andrew on Feb 24, 2012 23:32:37 GMT
Another issue is that your blocks are not identically coloured and are mainly silver coloured.
Which means conduction in air tends to be emphasised.
Painting them matt black is the way to do it.
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Post by Andrew on Feb 24, 2012 23:39:53 GMT
Magellan You were supposed to be doing a radiation experiment. There are advantages to doing this experiment in a vacuum but the set up may yet work with some changes. i, it was unreasonable to put the metal so close together because of conductivity in air issues. ii, the two blocks should be so heated that when cooling they are already close to their equilibrium temperatures. The warmer colder block then sends more radiation to the hotter block than is received from the room temperature surroundings. iii, the unheated room temperature block cannot send more radiation to the heated block unless the cold block begins warming. But it is metal and removes heat from the heated surface very quickly. 1. Please repeat this experiment with the faces 10cm apart. 2. Heat the two pieces in the oven as before to 150. Or better have two ovens. one at 150 and the other at 130 3. If you only have one oven, remove one piece only, insert a thermocouple and wrap it in insulation foil and rock wool. Leave it till it is 130 on the outside surface. 4. Place the metal 10cm apart and measure the outer faces and inner faces of both. I am going to do something similar here in Finland. If you can prove me wrong then you have demolished the green house theory. So it is worth the effort to demonstrate it in a manner that other people will be convinced by. Currently your method has at least two major issues. And for sure unless you prove failure in a vacuum you will not get credibility. However if should work with changes so if it does not you could be famous. Of course there was nothing wrong with your mickey mouse setup I don't see the need to measure the temperature of the colder object. It will warm, QED. I am only interested in observing a difference in rate of cooling of the hotter object as you have stated will occur due to back radiation. No skin off my back if I'm wrong. In fact, I asked for radiative transfer equations in hopes of discovering why my observations did not follow what you predicted. BTW, have you bothered to check what the specific heat content and thermal conductivity of air is? Ridiculing me does not make you a good scientist. My arrangement demonstrated an effect. If another person does a better arrangement and they get no results then that is science in action - if they are able to do the necessary work and realise what they are testing for. If your cold face only warms a tiny amount then with surface irregularities and uneven colouring - as you have, then these other differences could overwhelm the small difference you expect to see to the point of reversing it. You also seem to be refusing to acknowledge that you need an approximately uniform colder environment without heat souces around the blocks. The more things you decide are irrelevant the more mickey mouse your super expensive arrangment ends up becoming I did check the conductivity of air and checked on a large number of specific heat contents of things like granite bricks wood lead and so forth. I am going to arrange a set up with matt black concrete blocks with 4 identical thermocouples. I am already running such an experiment without the matt black and i can see warmer facing temperatures using the radiation thermometer, but using a hand held radiation thermometer is far from ideal
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Post by magellan on Feb 24, 2012 23:44:18 GMT
Another issue is that your blocks are not identically coloured and are mainly silver coloured. Which means conduction in air tends to be emphasised. Painting them matt black is the way to do it. If they are equal in finish, why would it matter? You are intent on continuously moving the goal posts, but ok, I'll play despite having never read in any heat transfer examples it "is the way to do it".
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Post by Andrew on Feb 24, 2012 23:48:14 GMT
Another issue is that your blocks are not identically coloured and are mainly silver coloured. Which means conduction in air tends to be emphasised. Painting them matt black is the way to do it. If they are equal in finish, why would it matter? You are intent on continuously moving the goal posts, but ok, I'll play despite having never read in any heat transfer examples it "is the way to do it". I am not moving the goal posts at all. I am just asking you to do it properly. My mickey mouse arrangement demonstrated a strong effect so did not need to be more sophisticated. Your objections to it seem mainly driven by your faith that no effect could be demonstrated so me saying a strong effect was shown is proof of how mickey mouse it was. Science does not work that way.
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Post by magellan on Feb 24, 2012 23:53:53 GMT
Of course there was nothing wrong with your mickey mouse setup I don't see the need to measure the temperature of the colder object. It will warm, QED. I am only interested in observing a difference in rate of cooling of the hotter object as you have stated will occur due to back radiation. No skin off my back if I'm wrong. In fact, I asked for radiative transfer equations in hopes of discovering why my observations did not follow what you predicted. BTW, have you bothered to check what the specific heat content and thermal conductivity of air is? Ridiculing me does not make you a good scientist. My arrangement demonstrated an effect. If another person does a better arrangement and they get no results then that is science in action - if they are able to do the necessary work and realise what they are testing for. If your cold face only warms a tiny amount then with surface irregularities and uneven colouring - as you have, then these other differences could overwhelm the small difference you expect to see to the point of reversing it. You also seem to be refusing to acknowledge that you need an approximately uniform colder environment without heat souces around the blocks. The more things you decide are irrelevant the more mickey mouse your super expensive arrangment ends up becoming I did check the conductivity of air and checked on a large number of specific heat contents of things like granite bricks wood lead and so forth. I am going to arrange a set up with matt black concrete blocks with 4 identical thermocouples. I am already running such an experiment without the matt black and i can see warmer facing temperatures using the radiation thermometer, but using a hand held radiation thermometer is far from ideal Like they say, what comes around goes around. Now that you've dumped your posts down the rabbit hole, nobody will ever know. Of course the thermocouples will be calibrated with stated accuracies and use the appropriate ones, i.e. contact probes and not immersion probes. How many times can I say this; an IR thermometer is a WASTE OF TIME for such experiments. Ten people will get ten different readings. If you can't use the proper equipment in the proper conditions and do not have the capability of validating the measurements, there is no sense in continuing this discussion. And yes I will be the judge of whether your setup and procedure is legitimate; if you don't like that, tough.
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Post by Andrew on Feb 24, 2012 23:54:18 GMT
If they are equal in finish, why would it matter? 1. They do not appear equal in finish 2. you want to maximise the radiation effect over the other ways of cooling where between two hot faces in air you will get convection 3. The only way to know if they are equal is to reverse the set up and so forth, otherwise all you have is your faith it does not matter. There are 4 different ways of arranging the blocks to find out if they are equal. Either way silver is not a good idea
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Post by sigurdur on Feb 25, 2012 0:21:06 GMT
Ok.............let's make this simple. 1. Does everyone agree that all objects above absolute zero emit radiation? ? Let's start with a very simple premiss and see if we can build on that.....ok?
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