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#1280 by dustinthewind on 05 Jan, 2016 05:56
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One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust. -
#1281 by TheTraveller on 05 Jan, 2016 12:14
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One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust.
Imagine if the Rf power started out at 80 mW and that power level was used to find the resonance sweet spot via min VSWR. Then once the resonance sweet spot is found, apply 100W Rf pulses from 20% of 1 TC (3.5 usec) to 10 TC (35 usec) to measure Thrust generated on a strain gauge and determine the best Rf pulse length to Specific Force based on real measured forward power. The frustum would not even get warm. Ok will probably need a circulator and Rf dummy load to handle the initial high level of reflected power to avoid stressing the Rf amp.
Then arrange 8 frustums and cycle the Rf pulse between them. Result is any thermal problem is basically solved as the 7 non powered frustums thermally reset to idle conditions before being powered on again.
Roger and his SPR team are clever boys. -
#1282 by Flyby on 05 Jan, 2016 12:33
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(...)
Then arrange 8 frustums and cycle the Rf pulse between them. Result is any thermal problem is basically solved as the 7 non powered frustums thermally reset to idle conditions.
Roger and his SPR team are clever boys.
Basically, a Gatlin-gun principle...1861...old wine in new bottles...
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#1283 by Rodal on 05 Jan, 2016 12:38
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Answered at length here: https://forum.nasaspaceflight.com/index.php?topic=39214.msg1470152#msg1470152One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust. -
#1284 by TheTraveller on 05 Jan, 2016 12:40
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(...)
Then arrange 8 frustums and cycle the Rf pulse between them. Result is any thermal problem is basically solved as the 7 non powered frustums thermally reset to idle conditions.
Roger and his SPR team are clever boys.
Basically, a Gatlin-gun principle...1861...old wine in new bottles...
Good engineers don't reinvent the wheel. If an existing engineering technique works, it is proven and you are comfortable using it, you use it. Then move on to the next engineering challenge.
I much prefer to enjoy the old wine with a group of good friends. -
#1285 by rfmwguy on 05 Jan, 2016 12:54
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The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
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#1286 by TheTraveller on 05 Jan, 2016 13:01
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The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
What can I say?
Magnetically suspended rotary test rigs. The ONLY way to do this!
OK fair cop, I still need to build this wonder machine. Fear not it is in progress. -
#1287 by Rodal on 05 Jan, 2016 13:07
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The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
<<Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.>>
Please explain why thermal expansion effects are not pertinent to a vertical test bed.
Thermal expansion and thermoelasticity (whether thermal expansion resulting in changes in length or in thermal forces as buckling or any thermal force arising from thermal expansion) in general takes place in any configuration in any frame of reference with materials experiencing changes in temperature.
Moreover, concerning "DIY territory" SeeShells recognized early on the importance of thermal expansion effects and that's part of the reason why she went through the trouble, time and expense of using a carbon-epoxy pultruded beam for her "vertical vector test bed".
Published papers with analysis cannot just be dismissed with a statement that they are not useful because you say so. It is not enough to state <<Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.>> . You need to back your statements with analysis so as not to appear to be dismissing of other's work.
And concerning DoItYourself experiments, one can not just dismiss SeeShells expenditure of time and money in using a pultruded carbon-epoxy beam (to address thermal expansion and stiffness) for her experiment. See following example that applies both to your experiment and Shell's experiment with a balanced beam with the EM Drive on one side:
_____________
Trivial example of the relevance of thermal expansion effects for a balanced beam in vertical configuration:
If you have a balanced beam in a vertical configuration such that
W1 * L1 = W2 * L2
where W1 and W2 are the weights and L1 and L2 are the moment arms
and differential thermal expansion occurs such that the length L2 on the right hand side stretches to L3 with L3>L2
because the EM Drive is only on one side of the balance and thus one side of the balance is primarily affected by thermal effects arising from the EM Drive induction heating and conducting as well as radiating and convecting heat primarily on one side of the balance
you will now have, as a result of differential thermal expansion
W1 * L1 < W2 * L3
and the balance will move down to the right hand side simply as a result of the fact that the moment arm on the right side is greater than on the left hand side
Thus it is trivial to show that differential thermal expansion effects affect such a configuration at its most basic level. -
#1288 by rfmwguy on 05 Jan, 2016 13:25
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Yes. Fair enough Phil...you might have a superior test bed concept for sure. All we need now are pics and data
The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
What can I say?
Magnetically suspended rotary test rigs. The ONLY way to do this!
OK fair cop, I still need to build this wonder machine. Fear not it is in progress.
you knew I was going to say that...lol
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#1289 by rfmwguy on 05 Jan, 2016 13:34
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No offense dr rodal, sorry may have taken it that way. I did not read any useful data that directly correlated to vertical displacement measurements. If I overlooked them, please point them out....
The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
<<Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.>>
Please explain why thermal expansion effects are not pertinent to a vertical test bed.
Thermal expansion and thermoelasticity in general takes place in any configuration in any frame of reference with materials experiencing changes in temperature.
Moreover, concerning "DIY territory" SeeShells recognized early on the importance of thermal expansion effects and that's why SeeShells went through the trouble, time and expense of using a carbon-epoxy pultruded beam for her "vertical vector test bed".
Published papers with analysis cannot just be dismissed with a statement that they are not useful because you say so. It is not enough to state <<Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.>> . You need to back your statements with analysis instead of dismissing other's work.
And concerning DoItYourself experiments, you can not just dismiss SeeShells expenditure of time and money in using a pultruded carbon-epoxy beam (to address thermal expansion and stiffness) for her experiment. If you think that SeeShells did not spend her time and/or money wisely using such a pultruded carbon-epoxy beam for her experiment (because you think that thermal expansion effects are not important for these experiments), you need to show why that is so.
I can only speak for my own tests regarding thermal buckling. Since my frustum had non rigid sidewalls and copper clad pc board endplates, the copper buckling predictions of your paper were non-applicable, not generally dismissable as you stated. -
#1290 by oyzw on 05 Jan, 2016 13:47
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I think there is no need to try to convince skeptics, under the condition of with abundant capital, production of high temperature superconducting cavity will be more directly to save time.To increase the thrust to strong enough, can eliminate the little interference factors.
The thermal buckling paper of dr rodal and mr li's lorentz paper are quite useful in identifying potential error sources on torsional or horizontal test beds. A change in center of mass or magnetic deflection both could compromise torsional measurements.One of the big questions, it seems to me, about thermal effects is not so much the magnitude, but the time constant with which these effects act. What would it take to put a number on the time constant of buoyant effects?
Copper, good copper, is expensive so would an aluminium cylinder designed to resonate at 2.45 - 2.47 GHz, operated and tested for thermal effects provide time constant data that could be used in the data analysis of a given copper frustum experiment? If yes, then could a coffee can, or on oatmeal box lined with foil be used to good effect?
Just speculating on a way to determine if the thermal response is quick or slow. Use a cylinder because that should not thrust by all we currently know.
Rodal posted this back a few pages. It may or may not relate to other frustums and would probably depend on material thickness ect. It is the researchgate link. http://forum.nasaspaceflight.com/index.php?topic=39004.msg1468340#msg1468340 I think it mentioned time to buckle if I remember correctly.
Edit: I don't think much long term thrust could be had from this after thermal equilibrium is reached. The force should decrease with time as the thermal expansion decelerates. It might be helpful to know the time to thermal equilibrium.
Edit2: Also, any positive thrust signal observed due to thermal expansion should be an equal and opposite signal upon powering down. Thermal contraction would give a negative thrust.
If I might summarize (corrections encouraged) both papers claim roughly 50 micronewtons of potential tortional error force, therefore close to 100 micronewtons total. This is by coicidence the total reported torsional force by EW.
From what I've, read EW has measured single digit lorentz in their new setup but am not sure they addressed rodals buckling paper, so in summary, all we have before us is a potential torsional error force of let's say about 60 micronewtons.
Neither paper is all that useful, imho, for a vertical vector test bed, namely a balance beam which is diy territory for the most part.
I would encourage anyone to help put forth a paper or proposal that quantifies potential vertical error forces. I know shell is working on her own error analysis and I'm sure additional systemic vertical error forces would be quite useful to her and other diyers...who are growing in numbers.
Since thermal lift is the culprit in ambient air, might I suggest statistical analysis of rf power on and off conditions, possibly simplified down to an acceleration variance, such as micrometers/second. This proposal would characterize any vertical acceleration changes RF on to RF off. Statistical variances could then point to the need for more error reducing measurements such as mass or localized airflow...perhaps via schlieren photography.
Just some rambling thoughts for vertical-bound diyers. Neither dr rodal'snor mr li's papers seem to be useful for non-torsional test beds. Torsional yes, non-torsional no.
What can I say?
Magnetically suspended rotary test rigs. The ONLY way to do this!
OK fair cop, I still need to build this wonder machine. Fear not it is in progress. -
#1291 by OnlyMe on 05 Jan, 2016 14:02
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(...)
I think there is no need to try to convince skeptics, under the condition of with abundant capital, production of high temperature superconducting cavity will be more directly to save time.To increase the thrust to strong enough, can eliminate the little interference factors.
The problem with this reasoning, is that it appears that until someone does convince skeptics, unlimited funding is an unrealized dream.
There is also an issue that involves just what is patentable! An example is that while you can patent a specific gasoline engine, you cannot patent all gasoline engines.
You can't patent the physics. The component parts are almost all available for sale, as existing technologies, produced by multiple manufactures.
A patent that covers all of the variations in the patentable components would be larger than the US tax code.
Unless someone like NASA, decides to develope the tecology, for their own purposes... -
#1292 by glennfish on 05 Jan, 2016 14:10
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(...)
I think there is no need to try to convince skeptics, under the condition of with abundant capital, production of high temperature superconducting cavity will be more directly to save time.To increase the thrust to strong enough, can eliminate the little interference factors.
The problem with this reasoning, is that it appears that until someone does convince skeptics, unlimited funding is an unrealized dream.
I've done a few startups in my time and worked due diligence for a few VCs.
The issue is simple, whether it's an EMDrive or a straw that provides chocolate flavor when you drink milk through it.
You walk into a conference room for an hour, and during that hour, you get a demonstration. If the demonstration appears to work, then you send in your due diligence team that looks at the guts, the theories, the physics, whatever it is they can think of to prove it's a bad investment. If they find anything that says it might not be real, the audience is over.
To this point, no one has gotten to the point where they could waltz into the conference room and survive for an hour. Until that happens, there will be no bucks. -
#1293 by rfmwguy on 05 Jan, 2016 14:21
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Funding is to some extent crowdfunding or self-funding by diyers. Minimal public funding or corporate funding exists best I can determine, thus a stalemate until a breakthrough is achieved.(...)
I think there is no need to try to convince skeptics, under the condition of with abundant capital, production of high temperature superconducting cavity will be more directly to save time.To increase the thrust to strong enough, can eliminate the little interference factors.
The problem with this reasoning, is that it appears that until someone does convince skeptics, unlimited funding is an unrealized dream.
There is also an issue that involves just what is patentable! An example is that while you can patent a specific gasoline engine, you cannot patent all gasoline engines.
You can't patent the physics. The component parts are almost all available for sale, as existing technologies, produced by multiple manufactures.
A patent that covers all of the variations in the patentable components would be larger than the US tax code.
Unless someone like NASA, decides to develope the tecology, for their own purposes...
Considering the ramifications if emdrive is finally validated, surprised how little money has been allocated.
Of course I will make no analogy to searching for treasure on Oak Island...emdrive is way behind in speculative monies spent by comparison
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#1294 by rfmwguy on 05 Jan, 2016 14:47
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Ok dr rodal, you've added some more info. To keep posts shorter, will not quote it.
If I understand correctly, you are stating the thermal expansion of a moment arm itself, not the DUT?
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#1295 by rfmwguy on 05 Jan, 2016 14:53
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Sorry, device under test. I thought your paper refered to buckling of a device under test and not that of a test stand.Ok dr rodal, you've added some more info. To keep posts shorter, will not quote it.
What does the DUT acronym mean ?
If I understand correctly, you are stating the thermal expansion of a moment arm itself, not the DUT? -
#1296 by Rodal on 05 Jan, 2016 14:59
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My post was in response to someone asserting that thermal effects cannot occur fast enough to justify the anomalous force vs. time measured. I quoted the analysis in my paper to show by just one example that the assertion is false.
Sorry, device under test. I thought your paper refered to buckling of a device under test and not that of a test stand.Ok dr rodal, you've added some more info. To keep posts shorter, will not quote it.
What does the DUT acronym mean ?
If I understand correctly, you are stating the thermal expansion of a moment arm itself, not the DUT?
Basically, thermal expansion occurs at the speed of sound in the material experiencing the thermal expansion. This speed is much faster than the slow effects others are assuming.
Thermal expansion will result in changes in length for a material that is unrestrained and it will result in thermal forces for a material that is restrained.
In general all real structures are made of deformable materials, there are no perfectly rigid materials in nature.
The effects of thermal expansion can be shown to be present in both the horizontal torsional experiments as well as what you refer to as vertical balance beam experiments.
My first post at NSF was on the thermal expansion shifting of the center of mass effect. Paul March has accepted that the shifting of the center of mass effect by thermal expansion is present in their experimental measurements (both in air and in partial vacuum) and that it is so pervasive that they were trying to model it to be able to account whether there is really an anomalous force (and if so how large, after accounting for the effect of thermal expansion).
In the trivial example above, I have shown how differential thermal expansion of the vertical balance beam will move the beam down to the right if the EM Drive is located at the right of the balance. -
#1297 by rfmwguy on 05 Jan, 2016 15:05
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This is a valid point, but for expansion to have an error produced on vertical displacenent or balance beam measurements, wouldn't the only error be caused by thermal expansion of the moment arm itself?
My post was in response to someone asserting that thermal effects cannot occur fast enough to justify the anomalous force vs. time measured. I quoted the analysis in my paper to show by just one example that the assertion is false.
Sorry, device under test. I thought your paper refered to buckling of a device under test and not that of a test stand.Ok dr rodal, you've added some more info. To keep posts shorter, will not quote it.
What does the DUT acronym mean ?
If I understand correctly, you are stating the thermal expansion of a moment arm itself, not the DUT?
Basically, thermal expansion occurs at the speed of sound in the material experiencing the thermal expansion. This speed is much faster than the slow effects others are assuming.
Thermal expansion will result in changes in length for a material that is unrestrained and it will result in thermal forces for a material that is restrained.
In general all real structures are made of deformable materials, there are no perfectly rigid materials in nature.
The effects of thermal expansion can be shown to be present in both the horizontal torsional experiments as well as what you refer to as vertical balance beam experiments. -
#1298 by Rodal on 05 Jan, 2016 15:14
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This is a valid point, but for expansion to have an error produced on vertical displacenent or balance beam measurements, wouldn't the only error be caused by thermal expansion of the moment arm itself?
My post was in response to someone asserting that thermal effects cannot occur fast enough to justify the anomalous force vs. time measured. I quoted the analysis in my paper to show by just one example that the assertion is false.
Sorry, device under test. I thought your paper refered to buckling of a device under test and not that of a test stand.Ok dr rodal, you've added some more info. To keep posts shorter, will not quote it.
What does the DUT acronym mean ?
If I understand correctly, you are stating the thermal expansion of a moment arm itself, not the DUT?
Basically, thermal expansion occurs at the speed of sound in the material experiencing the thermal expansion. This speed is much faster than the slow effects others are assuming.
Thermal expansion will result in changes in length for a material that is unrestrained and it will result in thermal forces for a material that is restrained.
In general all real structures are made of deformable materials, there are no perfectly rigid materials in nature.
The effects of thermal expansion can be shown to be present in both the horizontal torsional experiments as well as what you refer to as vertical balance beam experiments.
Anything in the balanced beam that increases the moment will result in shifting the equilibrium point of the balance. Anything that shifts the location of the center of mass will affect the balance. Thermal expansion occurs at the speed of sound, the question is how fast does the temperature increase at a given point in the structure. Induction heating by the RF electromagnetic fields occurs at the speed of light. Diffussion speed is governed by thermal diffusivity and the length path (the Fourier time). Thermal radiation occurs at the speed of light. Only thermal convection speed is constrained by the speed of thermal convection of the atmospheric fluid flow.
Concerning thermal forces like thermal buckling, they have to be balanced by inertia (mass times acceleration) if there is dynamic buckling as well as the restraining structure and therefore depends on the particular measuring system and how is material thermal expansion constrained.
The relatively long length of the vertical balance arrangement makes the differential thermal expansion of the balance beam something that should be analyzed and hence SeeShells may be justified in using a pultruded carbon-epoxy beam to ameliorate the differential thermal expansion.
Due to the extremely small forces that are being claimed in experimental reports, all these measurement systems are plagued by thermal effects and I agree with oyzw (as recommended by Prof Yang) that it would be more convincing to produce greater forces that clearly rise above thermal effects, as analysis of thermal effects is not trivial and it has not always been the focus in many experimental reports
Thermal effects cannot be simply and generally dismissed on account that "they are too slow" or that "they are too small" or that "they are not present in my measuring system" without analysis showing that to be the case. -
#1299 by TheTraveller on 05 Jan, 2016 15:17
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Considering the ramifications if emdrive is finally validated, surprised how little money has been allocated.
Of course I will make no analogy to searching for treasure on Oak Island...emdrive is way behind in speculative monies spent by comparison
2016 is really going to be an interesting year.
And yes Dave there will be pictures, videos and data streams to address accelerative CofE. As far as I'm concerned CofM is a not issue.
Just a mid set jump to the left and a step to the right.
you knew I was going to say that...lol