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#1300 by SeeShells on 05 Jan, 2016 15:26
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Not a lot of time so i'll make this quick and dirty it the simple things I did to negate thermal issues and warpages of the frustum. I've not eliminated all of them but I believe I have got them into a area that I can profile them.
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.
Back in August I started with carbon fiber wound very low thermal coefficient stiff rods for the "heart".
I did a couple of simple drawings that will show how I'm accounting for thermal copper buckling deviations, thermal copper expansion and growth, log balloon heating effects from a heated cavity. I think it helps to revisit my efforts to minimize any thermal issues.
http://imgur.com/1Uu6Arg This first one is used to map the thermal heating in the frustum from a ballooning effect.
http://imgur.com/0iFoMaU This one will show any thrusts in a downward direction over coming any heated cavity rises.
http://imgur.com/sKhYR2h This one shows releasing heated air down the beam with a relief tube negating any air jets from deflecting the sealed cavity or pressure warpages.
http://imgur.com/KykIeSQ This shows how the cavity side walls can heat and expand, sliding past the top plate still keeping tune.
http://imgur.com/x9Y4CD6 Top plate ceramic plate bottom is bonded with .032 O2 Free copper. Prevents the plate from deforming and buckling. Because of the energy distribution in the cavity from the modified TE012 mode it's mainly focused on the small top plate and side walls it's a heavier plate than the bottom.
http://imgur.com/ibPWYi3 This is the large bottom plate bonded onto a ceramic alumina plate to prevent warping.
Addressing the biggest error producer was to remove the magnetron from the cavity. If the standard unmodified power supply magnetron combination will not lock to the frequency of the frustum the heat is reflected back into the magnetron increasing the to be dissipated increasing the chaotic thermal effect even more.
The other is to make sure the injected RF into the cavity will not generate "hot spots" from simply deforming the modes. This can lead to a deformed cavity around a hot spot. Tajmar saw this. I addressed this issue with a symmetrical RF waveguide injection.
Summarize.
Low thermal growth fulcrum beam of carbon fiber
Stiffen the endplates with ceramic plates backing copper sheet to prevent buckling.
Remove the magnetron from the frustum.
Allow the walls of the frustum to grow by capturing the endplates with the Tuning Quartz rod
Seal the cavity but allow controlled evacuation of heated and expanded air.
Couple other points...
Stabilize magnetron output to a narrower bandwidth, prevent AM modulation of the output causing frequency splatter.
The cavity is going to want to heat up, we're injecting with up to 2000 Watts of RF energy, it's going to thermally expand. Simply let it. If you try to keep it from growing it will still thermally expand, one way or another uncontrolled. My goal on this build was to realize this and let it expand but control the expansion and keep the tune.
My other option was to encase it in a coffin of cement, hmmm interesting idea.
Work to do...
Shell
Need to proof reaD more but it is whAt it is, hate my new keyboard. Silly chicklett style keys!
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#1301 by rfmwguy on 05 Jan, 2016 15:48
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Ok, let me relate this from general to specific on my specific tests. Center of mass can only change IF a moment arm is affected by heat, thus increasing its length, thus decreasing its vertical displacement aka lift. My end plates were horizontal to floor, so no center of mass shift per your paper. Soooo...
Thermal expansion of a moment arm should be a concern in error measurements where endplates are horizontal to the floor.
This I can understand, but is not part of your paper, VERY useful however. Thank you.
p.s. Just like your oil bath dampening suggestion, you know I'm going to add thermal insulation to the end of the moment arm this year...just in case
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#1302 by rfmwguy on 05 Jan, 2016 16:11
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Thank you shell. At 2kW I can see why the source is remote...too much weight and thermal lift for sure. I do not visualize a center of mass change of a dangling frustum (hope I never have to use that term again) from a single point beneath a moment arm...but that's just me. Your expansion mitigations are well thought out. I would think you did this for maintaining fixed resonance rather than mass shift. Correct me if I'm wrong.
Sooo...any rf power delivery along the moment arm should take into account thermal expansion, or lengthening of the moment arm.
Chicklet keyboard...lol -
#1303 by frobnicat on 05 Jan, 2016 16:12
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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?
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.
Specifically in this case of length expansion of the beam's part from pivot to test article (length L), with a test article of constant mass m and no added/removed forces, the system will measure what would be equivalent to increase in downward force (without expansion) :
F=(ΔL/L)×mg=αL×ΔT×mg
αL the linear coefficient of expansion and ΔT the (assumed bulk) temperature change
usual metals are between 10 and 20 10-6/K (10 to 20 part per million per Kelvin, or Celsius)
Meaning that for a beam spanning 1m from pivot to suspension point of a 10kg test article (mg≈100N) a 0.1°C increase will typically record same as downward force above 100µN. Just to put things into perspective quantitatively...
Now you may argue that this is assuming bulk temperature increase and along the whole beam only from pivot to test article. Right, then we can go about heating a tenth of the beam's span by 1°C (say, a part directly above the test article), to the same result. Of course anisotropic heating, conduction and temperature gradients on thin or long pieces lead to various bendings and the rich phenomenology of buckling put forward by Rodal.
I think (intuitively, could be wrong) this kind of effect is drowned in comparison with buoyant and aerodynamic forces when testing on teeter totter balances in air. But clearly relevant for tests in vacuum with higher sensitivity.
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#1304 by rfmwguy on 05 Jan, 2016 16:21
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Cat, have to admire your ability to distill general into practical, complete with units. Regardless of small impact, thermal insulation of last foot or so of moment arm is an easy improvement just in case....
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?
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.
Specifically in this case of length expansion of the beam's part from pivot to test article (length L), with a test article of constant mass m and no added/removed forces, the system will measure what would be equivalent to increase in downward force (without expansion) :
F=(ΔL/L)×mg=αL×ΔT×mg
αL the linear coefficient of expansion and ΔT the (assumed bulk) temperature change
usual metals are between 10 and 20 10-6/K (10 to 20 part per million per Kelvin, or Celsius)
Meaning that for a beam spanning 1m from pivot to suspension point of a 10kg test article (mg≈100N) a 0.1°C increase will typically record same as downward force above 100µN. Just to put things into perspective quantitatively...
Now you may argue that this is assuming bulk temperature increase and along the whole beam only from pivot to test article. Right, then we can go about heating a tenth of the beam's span by 1°C (say, a part directly above the test article), to the same result. Of course anisotropic heating, conduction and temperature gradients on thin or long pieces lead to various bendings and the rich phenomenology of buckling put forward by Rodal.
I think (intuitively, could be wrong) this kind of effect is drowned in comparison with buoyant and aerodynamic forces when testing on teeter totter balances in air. But clearly relevant for tests in vacuum with higher sensitivity.
BTW, wood moment arms like mine have a low expansion coeffecient compared to metals. Here's a good chart
http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html -
#1305 by OnlyMe on 05 Jan, 2016 16:23
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Thank you shell. At 2kW I can see why the source is remote...too much weight and thermal lift for sure. I do not visualize a center of mass change of a dangling frustum (hope I never have to use that term again) from a single point beneath a moment arm...but that's just me. Your expansion mitigations are well thought out. I would think you did this for maintaining fixed resonance rather than mass shift. Correct me if I'm wrong.
Sooo...any rf power delivery along the moment arm should take into account thermal expansion, or lengthening of the moment arm.
Chicklet keyboard...lol
So you planning to dangle your frustum in phase II? Ah, no you mentioned just adding insulation between the frustum and beam.... -
#1306 by rfmwguy on 05 Jan, 2016 16:31
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Balance beam in my test is white oak, grain linear to length. Pivot point centered 53.5 inches from either end. Height is 1 inch, width is 0.75 inches. Light coating of enamel paint to inhibit moisture ingress/egress.
Edit - 177 micronewtons of equivalent force. -
#1307 by Rodal on 05 Jan, 2016 16:33
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Balance beam in my test is white oak, grain linear to length. Pivot point centered 53.5 inches from either end. Height is 1 inch, width is 0.75 inches. Light coating of enamel paint to inhibit moisture ingress/egress.
wasn't the anomalous force claimed to be 177 microNewtons in rfmwguy's experiment?
So with
<< for a beam spanning 1m from pivot to suspension point of a 10kg test article (mg≈100N) a 0.1°C increase will typically record same as downward force above 100>>microNewtons
how does
<<(intuitively, could be wrong) this kind of effect is drowned in comparison with buoyant and aerodynamic forces>>
follow?
Do we have a record of the temperature vs time of the weighted end of the beam to analyze ?
Can the thermal camera sensitivity be such as to measure 0.1 deg C or less with confidence?
the claimed anomalous force was of the same order as the back of the envelope calculation by Frobnicat for 0.1°C increase in a shorter length metal beam. rfmwguy's beam was 1.36 meters long from the end to the pivot instead of 1 meter.
0.1°C increase is a small increase in temperature...
don't know the weight of the suspended article
But the back of the envelope calculation by Fronicat is in the ballpark of the anomalous force claimed in rfmwguy's experiment -
#1308 by rfmwguy on 05 Jan, 2016 16:38
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Lol...I realize now that I dangled my frustum the minute I released my observational test report.Thank you shell. At 2kW I can see why the source is remote...too much weight and thermal lift for sure. I do not visualize a center of mass change of a dangling frustum (hope I never have to use that term again) from a single point beneath a moment arm...but that's just me. Your expansion mitigations are well thought out. I would think you did this for maintaining fixed resonance rather than mass shift. Correct me if I'm wrong.
Sooo...any rf power delivery along the moment arm should take into account thermal expansion, or lengthening of the moment arm.
Chicklet keyboard...lol
So you planning to dangle your frustum in phase II? Ah, no you mentioned just adding insulation between the frustum and beam....
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#1309 by aero on 05 Jan, 2016 16:40
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Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
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#1310 by OnlyMe on 05 Jan, 2016 16:49
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Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
Terminate a 3 or 4 point sling into a single lead. That should reduce or eliminate any shift in center of mass associated with an unequal expansion of leads. The issue then could be that the frustum might swing to some extent do to any thrust or shift in center of mass.., but that should be identifiable as cyclical. -
#1311 by SeeShells on 05 Jan, 2016 16:56
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Thank you shell. At 2kW I can see why the source is remote...too much weight and thermal lift for sure. I do not visualize a center of mass change of a dangling frustum (hope I never have to use that term again) from a single point beneath a moment arm...but that's just me. Your expansion mitigations are well thought out. I would think you did this for maintaining fixed resonance rather than mass shift. Correct me if I'm wrong.
Originally I was going to use a wooden composite beam for the reasons that it wasn't costly, it could be made to be quite stiff with additional supporting wires. This was where I stopped. By adding the stainless wire it also introduced a predetermined stress onto the beam. If the wire cooled or heated it could cause the deviation in the beam up or down. I elected not to introduce that into the build and went to carbon fiber tubes. That was one reason. The other was weight and needing greater thermal stability And one more thing was since the wire was running parallel to the power to the frustum I could be seeing Lorentz or heating induction into it and wasn't sure if I could isolate the wire from it.
Sooo...any rf power delivery along the moment arm should take into account thermal expansion, or lengthening of the moment arm.
Chicklet keyboard...lol
Shell
Back at it.
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#1312 by rfmwguy on 05 Jan, 2016 16:58
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(Sigh) Approximately 3.35 kg weight per side per my test report:
http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=38577.0;attach=1072184 -
#1313 by SeeShells on 05 Jan, 2016 17:05
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Balance beam in my test is white oak, grain linear to length. Pivot point centered 53.5 inches from either end. Height is 1 inch, width is 0.75 inches. Light coating of enamel paint to inhibit moisture ingress/egress.
Edit - 177 micronewtons of equivalent force.
Because the wire that you use to stiffen the beam for your hot dangling frustum I wonder what effects of thermal heat from your hot magnetron would have on the beam support wire and measurements? Maybe it would be interesting in your next runs before powering your frustum and magnetron up to heat up the wire directly above the magnetron with a heat gun or a hair dryer to see if you can see any beam deviation.
Shell
really I've got fun work to do! LaTer. I'm going ] to chuck this chicklett keyboaRd out the windoW... grr -
#1314 by rfmwguy on 05 Jan, 2016 17:06
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(Double sigh)Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
Terminate a 3 or 4 point sling into a single lead. That should reduce or eliminate any shift in center of mass associated with an unequal expansion of leads. The issue then could be that the frustum might swing to some extent do to any thrust or shift in center of mass.., but that should be identifiable as cyclical. 4-1 sling:
Don't know why I'm sighing, its not that I really expected anyone to remember my test report or videos...aka data OK, you can tell, I get frustumated at times.
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#1315 by aero on 05 Jan, 2016 17:18
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Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
Terminate a 3 or 4 point sling into a single lead. That should reduce or eliminate any shift in center of mass associated with an unequal expansion of leads. The issue then could be that the frustum might swing to some extent do to any thrust or shift in center of mass.., but that should be identifiable as cyclical.
I disagree. Reduce yes, eliminate, no. The termination point will also experience the change in force balance and move to accommodate it. At 3.35 kg mass it need only shift a very small distance,
distance = 0.000, 177 N/(3.35kg * 9.80665 N/kg) if my math is correct = 5.38775431931622E-06 or less than 6 μ m.
That number can not be hand waved away because waving your hand will cause more displacement than that.
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#1316 by SeeShells on 05 Jan, 2016 17:19
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I remember guy, watched them several times. This is the area I was thinking of and you might not see anything but the wire is in close proximity to the power, remember we are talking about only a small rise in temps.
(Double sigh)Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
Terminate a 3 or 4 point sling into a single lead. That should reduce or eliminate any shift in center of mass associated with an unequal expansion of leads. The issue then could be that the frustum might swing to some extent do to any thrust or shift in center of mass.., but that should be identifiable as cyclical. 4-1 sling:
Don't know why I'm sighing, its not that I really expected anyone to remember my test report or videos...aka data OK, you can tell, I get frustumated at times.
Now I really got to get.
Shell
added: Don't get flumesterated, just chatting here offering thoughts.
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#1317 by rfmwguy on 05 Jan, 2016 17:20
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Beam zupport wire terminates 14 inches from end and probably 10 more away from magnetron Itself.Balance beam in my test is white oak, grain linear to length. Pivot point centered 53.5 inches from either end. Height is 1 inch, width is 0.75 inches. Light coating of enamel paint to inhibit moisture ingress/egress.
Edit - 177 micronewtons of equivalent force.
Because the wire that you use to stiffen the beam for your hot dangling frustum I wonder what effects of thermal heat from your hot magnetron would have on the beam support wire and measurements? Maybe it would be interesting in your next runs before powering your frustum and magnetron up to heat up the wire directly above the magnetron with a heat gun or a hair dryer to see if you can see any beam deviation.
Shell
really I've got fun work to do! LaTer. I'm going ] to chuck this chicklett keyboaRd out the windoW... grr -
#1318 by OnlyMe on 05 Jan, 2016 17:55
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Thermal is the Gorilla in the room. We need to either fence him out as Shell is endeavouring to do, or cage him as I proposed with the cylindrical can proposal.
Thermal expansion effects on the DUT are likely very unique to each test rig. For example testing with a balance beam having the DUT suspended in a 4 point sling permits differential thermal expansion in each of the four suspension leads of the sling. Same with a 3 point sling. Same for a 2 point sling. Maybe a single point suspension like a rigid bar attached to the top center of the DUT extending upward a short distance then slung with a single lead from the balance beam. But that introduces other possible thermal effects.
Consider a 4 point sling. If one lead is heated more that the other 3, it will expand in length reducing the tension on that lead. The other 3 leads take up the slack and their tension increases. Seems to me this would shift the center of mass in the direction of the horizontal projection of the resulting force vector. This would be a very small shift but it would be multiplied by the total mass of the suspended test article.
But my thoughts here qualify as hand waving as I nor anyone else has specific data against which to measure any model of the thought experiment. I think someone has mentioned it before, "We need data."
Terminate a 3 or 4 point sling into a single lead. That should reduce or eliminate any shift in center of mass associated with an unequal expansion of leads. The issue then could be that the frustum might swing to some extent do to any thrust or shift in center of mass.., but that should be identifiable as cyclical.
I disagree. Reduce yes, eliminate, no. The termination point will also experience the change in force balance and move to accommodate it. At 3.35 kg mass it need only shift a very small distance,
distance = 0.000, 177 N/(3.35kg * 9.80665 N/kg) if my math is correct = 5.38775431931622E-06 or less than 6 μ m.
That number can not be hand waved away because waving your hand will cause more displacement than that.
If all you do is power on/off, it would seem hard to impracticle to extract any shifting of mass from thrust. If you power on and record thrust over time, by ending the multi-point suspension into a single lead, the center of mass shift should wind up a pendulum like cyclical signal.
I was speaking generically earlier, not specifically about rfmwguy's past experiments.
Unless someone measures thrust from a cold frustum, you are always going to have thermal noise to exclude.
If rfmwguy's phase II increases his measured thrust into the mN rage as I believe he is shooting for (single or double digit). Even the limited data from his earlier experiment will be of use.., and dismissing the anomalous thrust as thermal effects, difficult. -
#1319 by Moe Grills on 05 Jan, 2016 18:18
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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.
There are always...eccentric millionaires willing to put a larger chunk of their money into ideas and projects that fit their worldview or agenda. Hope you win the next lottery.
