ok @milehigh..so we have our gadolinium core at room temp wrapped with coils and send one d.c. oscillation pulse through.what happens if the core drops below its curie point from the resultant cooling end of the thermodynamic cycle..
Why do you use "spaces" in between words, but not after punctuation? ???
@point99..i,l start a thread on that issue later.meantime theres more important issues at hand.
Profits:
I read up a bit about gadolinium and the magnetocaloric effect, which I made reference to.
Quotewhat happens if the core drops below its curie point from the resultant cooling end of the thermodynamic cycle.
Your questions would be better if you could supply more details. Right now I am going to assume that the magnetocaloric effect might not even work if the core is above the curie point of 20 C. So the core will not cool down as per the magnetocaloric effect and your question itself is incorrect.
But I realize that your question is a lead in to the points that you want to make, so by all means please do so. Also, it has to be more than a few cryptic sentences, really explain your points in a clear and unambiguous fashion please.
For reference about the magnetocaloric effect:
QuoteThe magnetocaloric effect (MCE, from magnet and calorie) is a magneto-thermodynamic phenomenon in which a change in temperature of a suitable material is caused by exposing the material to a changing magnetic field. This is also known by low temperature physicists as adiabatic demagnetization, due to the application of the process specifically to create a temperature drop. In that part of the overall refrigeration process, a decrease in the strength of an externally applied magnetic field allows the magnetic domains of a chosen (magnetocaloric) material to become disoriented from the magnetic field by the agitating action of the thermal energy (phonons) present in the material. If the material is isolated so that no energy is allowed to (re)migrate into the material during this time, i.e., an adiabatic process, the temperature drops as the domains absorb the thermal energy to perform their reorientation. The randomization of the domains occurs in a similar fashion to the randomization at the curie temperature of a ferromagnetic material, except that magnetic dipoles overcome a decreasing external magnetic field while energy remains constant, instead of magnetic domains being disrupted from internal ferromagnetism as energy is added.
When they say, "agitating action of the thermal energy (phonons) present in the material," they mean that thermal energy in the material is used up to knock the magnetic domains into a random orientation and as a result that cools down the material.
When they say "energy is added" they mean that the material is above the Curie temperature and the large amount of ambient heat energy knocks the magnetic domains out of alignment.
MileHigh
@MH
Thank you for your explanation
I can see how this would lead people to believe they were seeing an overunity effect. This white mans magic is sure powerful stuff.
Kind Regards
PS Profitis, you never did answer my question why you did not assist Rosemary in her live demonstration?
@milehigh..ok i,l try put some parameters here.lets say weve designed the circuit to tailor-suit the properties of gadolinium and just got it right so that the temperature does drop below its curie point(easy to believe because the heat re-intake speed has to keep up with an almost instantaneous cessation of current in the core wires when switched off and thus necesarily much faster collapse of magnetic field than initial build-up of magnetic field)and thus goes from a paramagnetic material into a ferromagnetic material(greater order).so the order of our gadolinium atoms drasticly increase due to this extremely fast drop in temp(happens so fast we cannot perceive it).now we need a GREATER intake of heat than we exhausted to overcome this spontaneous increase of order of dipoles in our core and restore them to original random state.in other words we created a sinkhole for ambient heat with no expenditure of energy.the brief ferromagnetic state giving a stronger induction at moment of collapse than during paramagnetic buildup,what do you think so far milehigh..
@milehigh its analogous to compressing a gas in a syringe then releasing the plunger,BUT,the order of gas molecules spontaneously increase at moment of decompression requiring MORE heat intake than was exhausted out the syringe in the first place.what do you think.
Quote from: poynt99 on July 02, 2013, 08:10:08 PM
Why do you use "spaces" in between words, but not after punctuation? ???
I/THINK/IT:S/TO/ANNOY/READERS%
@markdansie..more like quantum magic here.i did tell you the reason in one of the threads,she refused to listen to my thermodynamic corrections..like so many others here.i might give her a shout soon and see how shes doing.maybe she,l listen to me now.
I would not count on you trying to reason with her , but maybe?
Anyway if you want your imagination fired read this.
MH do not tell me off for encouraging them lol
Mark
http://revolution-green.com/2013/07/03/magnetic-breakthrough-for-experimentors/ (http://revolution-green.com/2013/07/03/magnetic-breakthrough-for-experimentors/)
Profits:
Quotelets say weve designed the circuit to tailor-suit the properties of gadolinium and just got it right so that the temperature does drop below its curie point(easy to believe because the heat re-intake speed has to keep up with an almost instantaneous cessation of current in the core wires when switched off and thus necesarily much faster collapse of magnetic field than initial build-up of magnetic field)and thus goes from a paramagnetic material into a ferromagnetic material(greater order)
I don't see the huge significance of the Curie point here. It marks the transition point where magnetic domains are stable or not in the "mosh pit" of the jostling molecules. If you ignore the magnetic properties, then there is nothing. When you factor in the temperature, then you have two states, either you can store magnetic energy in aligned domains or you can't.
I don't have any context for "instantaneous cessation of current." Are you envisioning a test setup of some sort? If yes please describe it. Also, in reading the description of the effect it looks like you might actually want to decrease the current slowly, but I don't know what rate or if that is a true statement. In the brief description of the effect it says, "a decrease in the strength of an externally applied magnetic field" which tends to suggest a slow decrease. This will give the thermal energy enough time to make good "mosh pit hits" and knock the domains out of alignment.
You are wrong about the order change when you say, "thus goes from a paramagnetic material into a ferromagnetic material(greater order)." On the materials side, lower temperature means less order which equates to increasing entropy. In parallel with that you have the magnetic entropy of the material to factor in when it is below the Curie point temperature. When you magnetize and set up magnetic domains in the same direction you increase the energy level and decrease the associated magnetic entropy.
I think where you are going wrong is you are relating temperature change to the amount of magnetic order and they are two separate things. The total entropy would be the the entropy of the material as a function of temperature and the magnetic entropy as a function of magnetic domain alignment. What we can see is that the magnetocaloric effect allows for the transfer of small amounts of entropy (or energy) between the two types of entropy. However, it takes work to accomplish this. Note that you can look at this as just being a powered heat pump, just like the refrigerator in your kitchen. The key point being that you have to supply external power for this effect to work.
Quotenow we need a GREATER intake of heat than we exhausted to overcome this spontaneous increase of order of dipoles in our core and restore them to original random state.in other words we created a sinkhole for ambient heat with no expenditure of energy.the brief ferromagnetic state giving a stronger induction at moment of collapse than during paramagnetic buildup
I am assuming that the "sinkhole" for heat that you refer to is the magnetocaloric effect reducing the temperature of the gadolinium. The problem is that it is not happening like you think.
You assume that the magnetocaloric effect is going to operate on the gadolinium in a vacuum, i.e.; an adiabatic environment, if you want to bring the temperature down very close to absolute zero. You can imagine it happening in little steps. So the power cycle is when the coil is energized to create the magnetic field and line up the domains. Then most likely the current is slowly decreased and they let the heat in the gadolinium do the work of breaking up the magnetic domains. Then they do it again and again, perhaps thousands of cycles, to bring the material very close to 0 K.
Note the process is a powered process just like your kitchen fridge has to be powered. It's just another form of heat pump. The transition from above/below the Curie point is not all that significant in the scheme of things and I think that you are reading too much into it and making incorrect assumptions.
MileHigh
@milehigh..am i? Maybe, maybe not.allow us to examine the crux of the matter milehigh,the,as you said,entropy change in gadolinium when it passes through the curie point.the important question here is,does heat flow out of gadolinium the moment it undergoes this curiepoint quantum re-ordering to ferromagnetic,or,does heat flow in,or does no heat at all flow.what do you think,do you perhaps know the answer to this crucial question. Im reffering to gadolinium in general,not necesseraly this circuit.
Profits:
You are still not specifying the setup enough but I will answer anyways.
Without the presence of a magnetic field then when the gadolinium goes from above the Curie point to below the curie point nothing special happens at all. There is heat flow out of the metal but it is the normal heat flow. There is no "quantum reordering to ferromagnetic" like you are suggesting.
MileHigh
@milehigh nothing special happens? Are you sure.we take a rod of gadolinium and slowly,steadily reduce its temperature and the moment it passes below 19degree celcius theres no sudden puff of heat flow out of the rod to the environment at the moment of transition?are you certain milehigh.remember certain elements/compounds do give off a puff of heat when they crystallize as an analogy.
@milehigh.thers no sudden entropy change the moment we go below 19degree celcius,are you sure about this
@markdansie..ive got a secret to tell those pmm enthusiasts: the 'sticky point' of all these magnets on all these forums has nothing whatsoever to do with the possibility of obtaining a 2nd law breach and a self-propelled motion.the secret lies instead in the exchange of heat with the environment that happens when a magnet goes past a 'sticky point'.thus a sticky point is actually necessary for a yildits dream come true.
Profits:
Quote@milehigh nothing special happens? Are you sure.we take a rod of gadolinium and slowly,steadily reduce its temperature and the moment it passes below 19degree celcius theres no sudden puff of heat flow out of the rod to the environment at the moment of transition?are you certain milehigh.remember certain elements/compounds do give off a puff of heat when they crystallize as an analogy.
Please take the floor and say what you want to say.
MileHigh
@milehigh..so we have just confirmed that an exchange of heat occurs with the environment that did not originate in our battery.that 'puff' of heat that was expelled at the curie point did not originate in our refrigerator coils powered by the battery.instead,it originated from the core itself,thus we have 1 thermodynamic cycle within another thermodynamic cycle.heat flows out battery via core,lowers the temperature of core until passes curie point and at that instant a puff of heat flows out the core which didnt originate from the bat.If these cycles are performed at continuous oscillation,we have a fluctuating exchange of heat to and from the environment that is not originating from the battery.this fluctuation just by luck happens in fact AFTER the battery is switched off(cooling half of cycle).this fluctuation is registered by our coils and manifests as a increased total power on our kickback electrical pulses.where am i wrong milehigh.. 2 concurrent thermodynamic cycles which are additive,one triggering the other,but not feeding the other.where am i wrong
@milehigh,you must now infact prove to the jury that a heat exchange is going on with the environment that entirely originates from the battery.how are you going to do this now?
Quote from: profitis on July 04, 2013, 08:44:31 AM
so we have just confirmed that an exchange of heat occurs with the environment that did not originate in our battery.
Where and how was this "confirmed"?
PW
@pw..twas confirmed by multiple tests and measurments over the years by multiple physicists,engineers and library textbooks.its a thermodynamic 'peak' that happens when a substance undergoes phase change.in this case it is exothermic.
@milehigh quote 'on the materials side lower temperature means less order and greater entropy'.this statement of yours is incorrect.the truth is the opposite.
Quote from: profitis on July 04, 2013, 10:57:44 AM
@pw..twas confirmed by multiple tests and measurments over the years by multiple physicists,engineers and library textbooks.its a thermodynamic 'peak' that happens when a substance undergoes phase change.in this case it is exothermic.
Althouh the use of magnetocaloric materials in a system that causes transition of the Curie temperature increases the magnetocaloric effect and hence the pumping efficieny in refrigeration applications, I have never seen any research that indicates this process is more than 100% efficient.
Even iron exhibits the magnetocaloric effect, but some materials like Gd and Pr alloys and salts exhibit the effect to a much greater degree. But even with regard to materials that exhibit the giant magnetocaloric effect, I have never seen any research that indicates even these materials are somehow more than 100% efficient.
There has been a great deal of research over the past 100 years regarding use of the magnetocaloric effect for cooling, cryocooling, and more recently, as a replacement for the mechanical heat pumps in home refrigeration.
PW
@pw there has also been claimed over the years of discrepencies in those thermodynamics regarding magnetocaloric effect,why hasnt those discrepencies been put under the magnifying glass and thouroughly dealt with?in public at least?
Quote from: profitis on July 04, 2013, 12:16:50 PM
@pw there has also been claimed over the years of discrepencies in those thermodynamics regarding magnetocaloric effect,why hasnt those discrepencies been put under the magnifying glass and thouroughly dealt with?in public at least?
I have never seen such claims. But in using the magnetocaloric effect as it has been to approach zero degree Kelvin, one would think all manner of operation would have been placed "under the magnifying glass".
PW
@pw we cant realy capture,or utilize this fluctuation of heat with greater than 100% efficiency unless we use a circuit which is tailor-suited to the purpose.otherwise we burn too much fuel in our battery,or lose to much heat in our circuit,etc etc.its going to take trial and error to get it right in order to make sure that we cross the 100percent bridge.when it comes to ferrite cores the same rule applies,in a ferrite core the order of domains also increase for a split second just prior to collapse.
Quote from: profitis on July 04, 2013, 12:57:05 PM
@pw we cant realy capture,or utilize this fluctuation of heat with greater than 100% efficiency unless we use a circuit which is tailor-suited to the purpose.otherwise we burn too much fuel in our battery,or lose to much heat in our circuit,etc etc.its going to take trial and error to get it right in order to make sure that we cross the 100percent bridge.when it comes to ferrite cores the same rule applies,in a ferrite core the order of domains also increase for a split second just prior to collapse.
Sounds more like "speculation" than "confirmation"...
@pw..well isnt it funny that gadolinium and its alloys and salts are the choice material for refrigeration at greatest efficiency..mm..must be something to do with the curie point transition.the efficiency of our energy source will play a big role in getting over the 100percent mark.if we use our hand to move a magnet over gadolinium we wont cross the mark or register the mark as our body burns way too much fuel to do such work.we need a battery giving one pulse at a time in a coil around the gadolinium.we need to capture kickback one pulse at a time.
@pw..the only thing i can confirm is that gadolinium will without doubt liberate its own heat if the coils around it drop it to below its curie point.thus give a theoretical basis for building an overunity circuit around it.i can also confirm that the order of ferrite domains will undoubtedy increase if the coils around them drop their temperature,thus giving a theoretical basis for overunity circuits built around them.
Quote from: profitis on July 04, 2013, 01:29:43 PM
@pw..the only thing i can confirm is that gadolinium will without doubt liberate its own heat if the coils around it drop it to below its curie point.thus give a theoretical basis for building an overunity circuit around it.i can also confirm that the order of ferrite domains will undoubtedy increase if the coils around them drop their temperature,thus giving a theoretical basis for overunity circuits built around them.
Place a pece of Gd in a perfect thermal insuator.
Apply a magnetic field. Heat is released, but as the heat can't escape, the temperature of the Gd increases.
Remove the magnetic field. Heat is absorbed, but as none can come from outside, the temperature of the Gd decreases.
If the process were 100% efficient, the temperature of the Gd at the end of each cycle would be the same, regardless of whether the temperature swings transition the Curie temp or not. However, as the process is not 100%, the temperature of the Gd will rise with each cycle (i.e., some of the magnetization energy produces unwanted heating from other effects).
PW
Profits:
To me it looks like you are mixing up or mashing up the concepts of molecular phase change and the Curie point. When you transition past the Curie point temperature, no phase change takes place. There is no puff of energy released.
Also, heat is sucked from hot matter into another form for the magnetocaloric effect. There is never a release of heat like you are suggesting for the Curie point as far as I am aware of. And again, you have to supply power up front for the heat sucking to take place. In a way it's similar to expanding gas having a heat sucking effect.
The Curie point is just a threshold temperature that gauges the activity level of the molecular mosh pit. If the mosh pit is too active, then you can't get magnetic domains to line up. Drop the temperature a bit and the mosh pit settles down enough for magnetic domains to line up if there is an external influence. There is no thermal change per se that takes place at the Curie point.
So I disagree with your premise.
MileHigh
Quote from: MileHigh on July 04, 2013, 01:54:06 PM
Profits:
To me it looks like you are mixing up or mashing up the concepts of molecular phase change and the Curie point. When you transition past the Curie point temperature, no phase change takes place. There is no puff of energy released.
Also, heat is sucked from hot matter into another form for the magnetocaloric effect. There is never a release of heat like you are suggesting for the Curie point as far as I am aware of. And again, you have to supply power up front for the heat sucking to take place. In a way it's similar to expanding gas having a heat sucking effect.
The Curie point is just a threshold temperature that gauges the activity level of the molecular mosh pit. If the mosh pit is too active, then you can't get magnetic domains to line up. Drop the temperature a bit and the mosh pit settles down enough for magnetic domains to line up if there is an external influence. There is no thermal change per se that takes place at the Curie point.
So I disagree with your premise.
MileHigh
MH,
I believe the amount of heat released and absorbed by magnetocaloric materials is greater when those materials transition their Curie temps. However, even if the process were 100% efficient, the heat released and absorbed during each mag/demag cycle would be identical. Straddling the Curie temp is used in refrigeration cycles to increase pumping efficiency, but the process is still not 100%.
Some researchers have acheived COP=5 using magnetocaloric heat pumps to replace the mechanical heat pumps in consumer refrigerator prototypes.
However, just as with mechanical heat pumps, magnetocaloric heat pumps are not 100% efficient, regardless of the COP acheived.
PW
PW:
Thanks for the information. Something is telling me that magnetocaloric heat pumps are used in recreational vehicles but not for home refrigerators. Perhaps cost and energy efficiency are the determining factors?
MileHigh
Quote from: MileHigh on July 04, 2013, 02:33:57 PM
PW:
Thanks for the information. Something is telling me that magnetocaloric heat pumps are used in recreational vehicles but not for home refrigerators. Perhaps cost and energy efficiency are the determining factors?
MileHigh
MH,
I know of no currently available refrigeration systems for consumer use that rely on magnetocalorics (RV's or otherwise).
There is much research in this field however, as it would eliminate the use of fluid refrigerants and the moving parts associated with the mechanical heat pump. In theory, magnetocaloric heat pumps could be more efficient than their mechanical counterparts. However, materials costs have been one of several issues preventing their implementation.
As I understand, a recent breakthrough in alloying methods allows the use of less pure Gd to make suitable Gd(SiGe) alloys, for example, that reduces material costs while maintaining adequate pumping efficiencies. However, Gd remains a fairly expensive material. A breakthrough that eliminates the need for very expensive alloys and salts would go a long way toward bringing the technology to the consumer market.
I think it will be a bit longer before we see magnetocaloric refrigerators at Lowe's. However, a substantial amount of research and money is being applied toward that end.
PW
@milehigh,true.let me give another analogy.evrybody knows that if you take a permanent magnet and heat it,it loses magnetic strength.the opposite is also true thus if you cool a permanent magnet the domains fall into more orderly alignment and magnetic strength increases.thus in our inductor the aligned domains order suddenly increase at moment of cooling,thus magnetic field strength increases,thus back-inductance is stronger than forward-inductance.additional heat intake is now required to re-randomize those domains to original state due to this increased shifting alignment of domains.its a sinkhole for ambient heat.ambient heat ontop of heat exhausted by our battery.
Quote from: profitis on July 04, 2013, 04:05:46 PM
@milehigh,true.let me give another analogy.evrybody knows that if you take a permanent magnet and heat it,it loses magnetic strength.the opposite is also true thus if you cool a permanent magnet the domains fall into more orderly alignment and magnetic strength increases.thus in our inductor the aligned domains order suddenly increase at moment of cooling,thus magnetic field strength increases,thus back-inductance is stronger than forward-inductance.additional heat intake is now required to re-randomize those domains to original state due to this increased shifting alignment of domains.its a sinkhole for ambient heat.
How are you performing this "cooling"?
PW
@pw..the battery energy performs the cooling.the ambient energy plus the expelled battery energy performs the return to equilibrium.
Quote from: profitis on July 04, 2013, 04:21:00 PM
@pw..the battery energy performs the cooling.the ambient energy plus the expelled battery energy performs the return to equilibrium.
The battery energy produces heating.
In modern prototypes, electromagnets have been replaced with permanent magnets and the MC material is just moved into or out of the permanent magnetic field (or the magnets themselves moved).
In either case, application of a magnetic field to a magnetocaloric material liberates heat, i.e., increases its temperature.
PW
no picowatt,picture the magnetic domains in our inductor core as a type of elastic band.the battery heats up our elastic during stretching,heat dissipates to environment,then when we cut battery power off the rubber band snaps,instantly cooling the entire band,and the energy collected on our kickback load.im saying that the moment it cools we collect extra potential energy from sudden strengthening of rubber molecules.some ambient heat being added to stored battery energy(in the stretchd band)on collision with our fingers(ouch)
Quote from: profitis on July 04, 2013, 04:53:00 PM
no picowatt,picture the magnetic domains in our inductor core as a type of elastic band.the battery heats up our elastic during stretching,heat dissipates to environment,then when we cut battery power off the rubber band snaps,instantly cooling the entire band,and the energy collected on our kickback load.im saying that the moment it cools we collect extra potential energy from sudden strengthening of rubber molecules.some ambient heat being added to stored battery energy(in the stretchd band)on collision with our fingers(ouch)
This is exactly what I said, application of a magnetic field to a magnetocaloric material liberates heat, i.e., increases the material's temperature.
To produce cooling, the heat generated during the application of the magnetic field must be removed while the magnetic field remains in place (using liquid or air cooling for example).
When the magnetic field is then removed, the equivalent amount of heat removed while the material remained magnetized is absorbed by the material (assuming 100% efficiency).
The process is very analogous to most every other refrigeration cycle such as compressing a gas, which raises its temperature, extracting heat using air or liquid cooling, and then releasing the pressure on the gas so that it absorbs the heat that was extracted from it while pressurized.
Basic heat pump action, but not 100% efficient.
PW
@pw..aha,but why didnt you bring into question the temporary splitsecond increase of magnetic domain alignment in the cooling gadolinium when you suddenly removed your magnet.this happens extremely fast in a inductor,all at once when current cuts off.cooling happens so dramaticaly fast that if you took a snapshot of that moment you would see the domains even more aligned just prior to collapse than when they were created.
Quote from: profitis on July 04, 2013, 05:57:50 PM
@pw..aha,but why didnt you bring into question the temporary splitsecond increase of magnetic domain alignment in the cooling gadolinium when you suddenly removed your magnet.this happens extremely fast in a inductor,all at once when current cuts off.cooling happens so dramaticaly fast that if you took a snapshot of that moment you would see the domains even more aligned just prior to collapse than when they were created.
And with this post you lost me.
Just as the rate of heating would be during the magnetization phase, I would think that the rate of cooling during demagnetizaton would be dependent upon the material's thermal mass, thermal conductivity, and the thermal resistance to the environment.
Good luck with your experiments...
PW
@pw let me put this to you another way.the domains in the inductor core that have cooled down in front of the incoming devastating heat wave align to more order prior to their disruption.its as simple as that.magnetic field strength increases with decreasing temperature,this is pure fact.the degree to which this happens will depend on choice of core material.collapse happens much faster than buildup.buildup happens against a resistance,collapse happens with the resistance(rubber band,gas-piston).
@pw..picture a shockwave of heat moving from one end of core to the other end,each and every domain undergoes drastic cooling and increased order just before it is destroyed by the incoming heat wave. All this happens on our kickback stroke of the thermodynamic cycle.
@pw..try compress a gas,then release it,you will see what i mean.the decompression happens at a explosive pace,and so does the cooling.