Quote from: Mulletron on 11/11/2014 02:02 pmThe test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!NASA Ames Research Director’s Colloquium, August 12, 2014.discusses Infrared camera image of the Cannae test article at @36 minutesOf course, as posted previously, there is no heating of the exterior round lateral surface of the cone.White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.
The test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!
Quote from: Rodal on 11/11/2014 02:11 pmQuote from: Mulletron on 11/11/2014 02:02 pmThe test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!NASA Ames Research Director’s Colloquium, August 12, 2014.discusses Infrared camera image of the Cannae test article at @36 minutesOf course, as posted previously, there is no heating of the exterior round lateral surface of the cone.White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved...And even on this mostly copper apparatus we see not a lot of heat going out, "because it's High Q". But high Q or not, driven at resonance or not, power pumped in frustum should be dissipated from frustum. The RF amplifier heats a lot (comparatively). I don't find again the actual values of power injected for Cannae, nor the value of power injected to amplifier (as DC current of 5.6 A). I get that the RF amplifier has a limited efficiency (how much ?) and delivers less in microwave watts than it takes in DC watts, that would account for such a disparity in dissipated power from RF amplifier relative to frustum ? What when the RF power is less (like 2.6 W) : the amplifier eats less DC ( I remember someone told it was class AB...) or dissipates more (like a class A that takes as much power input, whether outputting AC or not) ?My doubt : is the microwave power (indicated as reference for all the experiments, like 16.9 W ...) really pumped in the cavity "one way" or isn't a large part of this power bouncing back at the RF amplifier and being dissipated there, making for a lower net power input to cavity ? Opinions from people knowing RF circuits and microwave generators better ?
Quote from: Rodal on 11/11/2014 02:11 pmQuote from: Mulletron on 11/11/2014 02:02 pmThe test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!NASA Ames Research Director’s Colloquium, August 12, 2014.discusses Infrared camera image of the Cannae test article at @36 minutesOf course, as posted previously, there is no heating of the exterior round lateral surface of the cone.White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved........
Quote from: frobnicat on 11/11/2014 06:28 pmQuote from: Rodal on 11/11/2014 02:11 pmQuote from: Mulletron on 11/11/2014 02:02 pmThe test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!NASA Ames Research Director’s Colloquium, August 12, 2014.discusses Infrared camera image of the Cannae test article at @36 minutesOf course, as posted previously, there is no heating of the exterior round lateral surface of the cone.White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved........Thank you for emphasizing that.The COMSOL FE analysis shows the electric field in the dielectric (Teflon PTFE) to be 20 to 50 times higher than elsewhere in the Cannae.However both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are non-polar, hence no dipole microwave heating can take place unless they contain some water molecules.PTFE ("Teflon") is also hydrophobic so not likely to contain water molecules and hence very unlikely to be microwave heated.Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper. Unfortunately the magnetic field is not shown. So no further comments on this unless we analyze the magnetic field in the Cannae.
Quote from: Rodal on 11/11/2014 07:25 pmQuote from: frobnicat on 11/11/2014 06:28 pmQuote from: Rodal on 11/11/2014 02:11 pmQuote from: Mulletron on 11/11/2014 02:02 pmThe test campaigns are discussed in the video too.@39:25 the slide says the conical frustum has a 4" dielectric resonator!?!?!NASA Ames Research Director’s Colloquium, August 12, 2014.discusses Infrared camera image of the Cannae test article at @36 minutesOf course, as posted previously, there is no heating of the exterior round lateral surface of the cone.White did not comment on interior heating of the big end or the insulation they placed on the exterior of the flat areas of the cone or the insulation they placed on the interior small end.What we see on the IR picture is the Cannae where there is no low thermal conduction PCB plate involved........Thank you for emphasizing that.The COMSOL FE analysis shows the electric field in the dielectric (Teflon PTFE) to be 20 to 50 times higher than elsewhere in the Cannae.However both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are non-polar, hence no dipole microwave heating can take place unless they contain some water molecules.PTFE ("Teflon") is also hydrophobic so not likely to contain water molecules and hence very unlikely to be microwave heated.Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper. Unfortunately the magnetic field is not shown. So no further comments on this unless we analyze the magnetic field in the Cannae.If I understand what you said. and the IR camera image from the presentation is not faked. Wouldn't that put a nail in the coffin of thermal effects artifact? At least as far as the Cannae testing is concerned.
He answers that the Alcubierre drive doesn't violate causality and that it cannot be used for time travel to the past because the spacecraft never travels faster than the speed of light in its local spacetime.
Quote from: Rodal on 11/11/2014 07:25 pm.../...Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper. Unfortunately the magnetic field is not shown. So no further comments on this unless we analyze the magnetic field in the Cannae.If I understand what you said. and the IR camera image from the presentation is not faked. Wouldn't that put a nail in the coffin of thermal effects artifact? At least as far as the Cannae testing is concerned.
.../...Both PTFE ("Teflon") in the Cannae and PE (polyethylene) in the truncated cone are also transparent to RF frequencies so negligible dielectric heating in them as well.So if there is any internal heating in the Cannae it must be the result of the electromagnetic field on the copper. Unfortunately the magnetic field is not shown. So no further comments on this unless we analyze the magnetic field in the Cannae.
Quote from: Rodal on 11/11/2014 02:11 pmHe answers that the Alcubierre drive doesn't violate causality and that it cannot be used for time travel to the past because the spacecraft never travels faster than the speed of light in its local spacetime.I remember an astrophysicist friend of mine and other people at physics forums saying that no matter if the local spacetime didn't change (warp) or you got instantaneously from one point to another (warp), it was still time travel to the past, because of the light cone or something like that. Any opinion Dr Rodal?
I have seen this stuff debated by others. What most physicists (including Alcubierre himself) agree with (except apparently Dr. White and a few others including a Portuguese scientist), is that the Alcubierre drive is not practically feasible and that wormholes remain as the only way to possibly ever travel superluminally. I haven't watched the movie "Interstellar" yet
Quote from: Notsosureofit on 11/11/2014 12:48 amQuote from: Rodal on 11/11/2014 12:00 amQuote from: Mulletron on 11/10/2014 11:50 pmFun to play around with:http://amrita.vlab.co.in/?sub=1&brch=280&sim=1518&cnt=4Nothing is suspended from a wire:Quote from: Brady, March, White, et.al.The pendulum arm pivots about two linear flexure bearings in a plane normal to gravitational acceleration. The flexure bearings provide an essentially-frictionless and hysteresis-free interface between the static test stand fixed structure and the dynamic pendulum arm. Test article force is measured by measuring the pendulum arm displacement and calculating the force via the flexure bearing spring constants that were determined during test facility setup NASA Eagleworks has an inverted pendulum.According to Paul March, NASA Eagleworks uses as a torsional spring two Riverhawk C-flex bearing blocks with torsional spring constant (http://flexpivots.com/cantilevered-single-ended-pivot-bearings/) centered 2.38" above and below the centerline of the 24.00" long by 1.50" Faztek aluminum pendulum arm. The long end of the pendulum arm is 15.5" from the torque pendulum's center of rotation, which makes the other short-end of the pendulum arm 8.5" from the center of rotation. However, the NASA report shows a linear flexure bearing http://flexpivots.com/linear-flexure-bearing/Well, the pic shows the bearing block anyway, not necc the c-flecs (always used c-flex me self back then)So, who are we to believe you think based on your experience and looking at the picture? (Honest question, not a trick question)The report that states linear bearing or Paul March that stated C-Flex bearing?
Quote from: Rodal on 11/11/2014 12:00 amQuote from: Mulletron on 11/10/2014 11:50 pmFun to play around with:http://amrita.vlab.co.in/?sub=1&brch=280&sim=1518&cnt=4Nothing is suspended from a wire:Quote from: Brady, March, White, et.al.The pendulum arm pivots about two linear flexure bearings in a plane normal to gravitational acceleration. The flexure bearings provide an essentially-frictionless and hysteresis-free interface between the static test stand fixed structure and the dynamic pendulum arm. Test article force is measured by measuring the pendulum arm displacement and calculating the force via the flexure bearing spring constants that were determined during test facility setup NASA Eagleworks has an inverted pendulum.According to Paul March, NASA Eagleworks uses as a torsional spring two Riverhawk C-flex bearing blocks with torsional spring constant (http://flexpivots.com/cantilevered-single-ended-pivot-bearings/) centered 2.38" above and below the centerline of the 24.00" long by 1.50" Faztek aluminum pendulum arm. The long end of the pendulum arm is 15.5" from the torque pendulum's center of rotation, which makes the other short-end of the pendulum arm 8.5" from the center of rotation. However, the NASA report shows a linear flexure bearing http://flexpivots.com/linear-flexure-bearing/Well, the pic shows the bearing block anyway, not necc the c-flecs (always used c-flex me self back then)
Quote from: Mulletron on 11/10/2014 11:50 pmFun to play around with:http://amrita.vlab.co.in/?sub=1&brch=280&sim=1518&cnt=4Nothing is suspended from a wire:Quote from: Brady, March, White, et.al.The pendulum arm pivots about two linear flexure bearings in a plane normal to gravitational acceleration. The flexure bearings provide an essentially-frictionless and hysteresis-free interface between the static test stand fixed structure and the dynamic pendulum arm. Test article force is measured by measuring the pendulum arm displacement and calculating the force via the flexure bearing spring constants that were determined during test facility setup NASA Eagleworks has an inverted pendulum.According to Paul March, NASA Eagleworks uses as a torsional spring two Riverhawk C-flex bearing blocks with torsional spring constant (http://flexpivots.com/cantilevered-single-ended-pivot-bearings/) centered 2.38" above and below the centerline of the 24.00" long by 1.50" Faztek aluminum pendulum arm. The long end of the pendulum arm is 15.5" from the torque pendulum's center of rotation, which makes the other short-end of the pendulum arm 8.5" from the center of rotation. However, the NASA report shows a linear flexure bearing http://flexpivots.com/linear-flexure-bearing/
Fun to play around with:http://amrita.vlab.co.in/?sub=1&brch=280&sim=1518&cnt=4
The pendulum arm pivots about two linear flexure bearings in a plane normal to gravitational acceleration. The flexure bearings provide an essentially-frictionless and hysteresis-free interface between the static test stand fixed structure and the dynamic pendulum arm. Test article force is measured by measuring the pendulum arm displacement and calculating the force via the flexure bearing spring constants that were determined during test facility setup
@Rodal - Did you write that the side walls of the cone are not subject to heating? Because if the side walls did warm the outside boundary layer of air then the warmer boundary layer would rise causing a reduced pressure over the outside of the cone walls. The result would be a net force toward the small end.
Quote from: aero on 11/11/2014 06:20 am@Rodal - Did you write that the side walls of the cone are not subject to heating? Because if the side walls did warm the outside boundary layer of air then the warmer boundary layer would rise causing a reduced pressure over the outside of the cone walls. The result would be a net force toward the small end. The balance design unfortunately does suffer some small amount of vertical to horizontal coupling as changes in vertical force can show up as small horizontal thrusts. This is one reason why Woodward's balance (and one supposes the one at Eagleworks) includes the ability to physically reorient the thruster to point left and right, so that sort of coupling can be subtracted out as common noise. Precise explanations of this out ought to appear in any peer review lit that eventually comes from Eagle.
This shows me that there is nothing anomalous about the response of the truncated cone: it is most probably due to thermal effects. Even a chemical thruster exhibits complex response. This is not the case here.
. . .all experimental work should be accompanied by analytical models of the testing equipment.. . .As frobnicat pointed out there is a huge amount of effort in trying to see the effects of the Quantum Vacuum and not enough effort to try to see the effect of classical physics.
....I see no reason for him to publish in peer review when he can get 3 other NASA centers to go after validation without risking anything. He's very shrewd that way.
Lost time is never found again.
When you write " to go after validation without risking anything. He's very shrewd that way" I don't understand what is not being risked and why is this being "shrewd".A scientist wants as much peer review as he can get. You want to publish in peer review journals. It is to your own benefit. If you are correct you get the recognition. If you are incorrect the sooner you find out the better. If others point out that you are missing something it is to your benefit. If one doesn't get peer review and discussion with other scientists, then one really may end up wasting precious years of your life in the wrong path and not really learn anything.
...And about the shrewdness thing. . .it is good to note that without publishing in peer review and putting out all the work this entails, Sonny has managed not only to redirect substantial NASA resources and DARPA funding onto his project, but now several NASA centers will be pursuing it. That is at the least, highly efficient, and he still hasn't stuck his neck out for his QVF model. That's more than shrewd. It's clever even. I'm not suggesting this is how science should be done, but he is getting what he wants. The trouble is, that eventually everyone will figure out the truth of the issue and the consequences of that will be interesting to say the least.