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Tuesday, March 3, 2015

NASA Emdrive experiments have force measurements while the device is in a hard vacuum

February 07, 2015


The Eagleworks team obtained EMDrive experimental force measurements in the torsional pendulum in a hard vacuum (~5.0x10^-6 Torr).

Paul March included their last null-thrust test that ran the RF amp at 10.0Adc while its RF power was being dissipated in a 100W, 50 ohm dummy load positioned in place of the test article on the torque pendulum (TP), a picture of the new heat shields for our torque pendulum's upper and lower torsion springs, (more belts and suspenders to mitigate thermal drifts in the TP baseline), the reversed test setup drawing and the best reversed thrust plot obtained just before or during when our second and last 120W max RF amplifier was dying from internal corona discharges around its RF output circulator.





Question "Is it possible to run the Frustum in a null configuration? If so, is that in the plans before the next report is published?"

Paul March Answer Yes and yes. In fact it was one of the requests made by the blue ribbon panel of PhDs that NASA/EP hired to review the Eagleworks Lab's theoretical and experimental work last summer. Even if will take a new mounting arrangement to get it accomplished.

Overall though the blue ribbon panel's experimentalists appeared to be pleased with our previous and upcoming lab work. However they ripped into Sonny's QVF/MHD conjecture because it relies on the quantum vacuum being mutable and engineer-able whereas the current physics mainstream thinks that the quantum vacuum is an immutable ground energy state of the universe that can-NOT be used to convey energy or momentum as proposed by Dr. White. However they brushed aside Sonny's QVF based derivation of the Bohr hydrogen atom electron radius as a "mathematical coincidence" and didn't have a word to say what the Casimir effect and other quantum vacuum phenomenon were caused by, that can only occur only if the QV is mutable and can convey energy and momentum. So Sonny and Jerry Vera took it upon themselves last fall to increase this mathematical coincidence from one to more than 47 times as they explored the QV created atomic electron shell radii for atoms up to atomic number 7 all based on the QV being the root cause for all of it including the origins of the electron and all other subatomic particles.

[In Paul March's Opinion] Jim Woodward's Mach-Effect (M-E) conjecture that is based primarily on SRT (Standard Relativity Theory] and GRT [General Relativity Theory], is still in the running for a way to explain his and our test results to date. However the M-E also has its detractors since it requires that instantaneous Wheeler/Feynman radiation reaction forces being required between a local time varying mass and all the other mass/energy in the casually connected universe, since this mechanism is used to balance the M-E's energy and momentum conservation books. In the end analysis though I think that the ME will rest on the quantum nature of space-time, since in Woodward's eyes the gravitational field IS space-time, and in our eyes GRT's space-time is in reality the quantum vacuum that probably has at least 4 spatial dimensions and one time dimension.




Paul provided a seven page thermal analysis of the EMDrive by Jerry Vera of NASA Eagleworks.

EMDrive thermal Analsis Conclusions of Jerry Vera – Eagleworks Lab January 4, 2015
• Heating occurs mostly on large OD end (27 °F temp rise) and very little heating shown on small OD end (less than 0.5°F temp rise)
• COMSOL Predictions of thermal heating shows very good qualitative agreement with Thermal IR data
• Agreement with IR data is best on copper surface but not as good for HDPE disks
• Need better HDPE disks thermal property data and dielectric loss factor to obtain a better match

From the Full EMDrive paper from six months ago

Talk Polywell had an interesting comment on the full paper

Eagleworks tested one tapered (frustum) cavity, aka Shawyer's EmDrive; and two Cannae drives which are also asymmetric but different resonant cavities. The Cannae drive is said to work on a purported different principle than the EmDrive, according to its inventor Guido Fetta (a net Lorentz force imbalance of electrons upon top vs bottom wall of the cavity). According to this purported working principle, one Cannae drive had radial slots on its rim as required by Fetta in order to produce net thrust, and the second Cannae drive didn't have those slits and was intended to be a "null test device". But the Cannae null test article… also produced net thrust (20 to 40 µN of net thrust depending of the forward or backward direction).

The null device having thrust means that the Cannae drive theory that the slits mattered was not true. However, this is irrelevant as to whether the Cannae drive produces thrust. Another theoretical explanation is needed but the anomalous thrust remains

We're talking of net thrust because of course the setup was also tested with a null 50 ohm load connected, in order to cancel the effect from the drives and detect any detect any spurious force due to EM coupling with the whole apparatus (which exists, at 9.6 µN) and this "null" spurious force was evidently subtracted from any thrust signal due to the drives then tested on the pendulum.

All tests articles (the EmDrive version, the Cannae drive version, and even the Cannae "null test" version) had a dielectric embedded within. This is a hint for a different theoretical explanation involving EM fields, proper acceleration, mass fluctuation and dielectrics. Maybe Mach effects (due to Mach's principle), as supposed by Woodward and Fearn within the GR theory, or within a scalar-tensor theory of gravity according to Minotti.



The Cannae drive website from 2011 is still available on the web archive. Guido Fetta's Q drive work and his expectation to revolutionize space travel are on the site.

Fetta's experimental results are detailed. Also, numerical work and what he believes are the Principles.


EMDrive thrust does not seem to scale with higher Q with these tests


What space missions are possible with early versions if this is true?

Based on test data and theoretical model development, the expected thrust to power for initial flight applications is expected to be in the 0.4 newton per kilowatt electric (N/kWe) range, which is about seven times higher than the current state of the art Hall thruster in use on orbit today. The following figures show the value proposition for this class of electric propulsion. A conservative 300 kilowatt solar electric propulsion roundtrip human exploration class mission to Mars/Deimos. A 90 metric ton 2 megawatt (MW) nuclear electric propulsion mission to Mars that has considerable reduction in transit times due to having a thrust to mass ratio greater than the gravitational acceleration of the Sun (0.6 milli-g’s at 1 AU). The same spacecraft mass performing a roundtrip mission to the Saturn system spending over a year around two moons of interest, Titan and Enceladus. Even in this last class of mission which requires only a single heavy lift launch vehicle, the mission has less mission duration than is common with a current conjunction-class Mars mission using chemical propulsion systems and which would require multiple heavy lift launch vehicles. 300 kW SEP Roundtrip Mission to Mars Deimos (50 day stay) departing from DRO 300 kW SEP



What are the next research steps ?

The lessons learned with antenna design and location have been factored in and the design of both the drive and sense antenna s have been explicitly optimized to excite the RF thruster at the target frequency and mode (e.g.,the optimal location has been analytically determined). The thrust performance of this next generation tapered test article has been analytically determined to be in the 0.1 newton per kilowatt regime. Vacuum compatible RF amplifiers with power ranges of up to 125 watts will allow testing at vacuum conditions which was not possible using our current RF amplifiers due to the presence of electrolytic capacitors. The tapered thruster has a mechanical design such that it will be able to hold pressure at 14.7 pounds per square inch (psi) inside of the thruster body while the thruster is tested at vacuum to preclude glow discharge within the thruster body while it is being operated at high power. A phase lock loop (PLL) solution has already been implemented and evaluated at the 1 GHz frequency range, and is being tailored to be able to support testing at multiple set points all the way up to 2.5 GHz. The near term objective is to complete a Q -thruster breadboard test article that is capable of being shipped to other locations which possess the ability to measure low thrust for independent verification and validation (IV&V) of the technology. The current plan is to support an IV&V test campaign at the Glenn Research Center (GRC) using their low thrust torsion pendulum followed by a repeat campaign at the Jet Propulsion Laboratory (JPL) using their low thrust torsion pendulum. The Johns Hopkins University Applied Physics Laboratory has also expressed an interest in performing a Cavendish Balance style test with the IV and V shipset

SOURCES - Paul March via NASA Spaceflightforum, Jerry Vera of Eagleworks Lab

February 20, 2015

Can the Emdrive Be Explained by Quantised Inertia?

An Introduction to MiHsC - a model for inertia called: Modified inertia by a Hubble-scale Casimir effect (MiHsC) or quantised inertia.

The idea of inertia is that in a vacuum, where there is no friction, objects move along in a straight line at constant speed until you push on them. This tendency was first isolated by Galileo, who rolled balls down inclined planes (balls feel less friction). This tendency, inertia, has always been assumed but never explained.

Meanwhile physics has moved towards a study of information, and it has been realised in the past few decades that when you accelerate something, say, to the right, information from far to the left can never catch up to it, this means there is an information-boundary or 'horizon' to its left which is like a black hole event horizon (it is called a Rindler horizon). A kind of Hawking radiation comes off this horizon, which is called Unruh radiation (it was proposed by Bill Unruh) and is seen as background radiation, but is seen only by the accelerated object.

The new prediction from the model then is that objects with very low acceleration lose inertial mass in a new wa

It has been shown that cone-shaped cavities with microwaves resonating within them move slightly towards their narrow ends (the emdrive). There is no accepted explanation for this. Here it is shown that this effect can be predicted by assuming that the inertial mass of the photons in the cavity is caused by Unruh radiation whose wavelengths must fit exactly within the cavity, using a theory already applied with some success to astrophysical anomalies where the cavity is the Hubble volume. For the emdrive this means that more Unruh waves are “allowed” at the wide end, leading to a greater inertial mass for the photons there. The gain of inertia of the photons when they move from the narrow to the wide end, and the conservation of momentum, predicts that the cavity must then move towards the narrow end, as observed. This model predicts the available observations quite well, although the observational uncertainties are not well known.

(H / T Adam Crowl at Crowlspace )

Three independent experiments have shown that when microwaves resonate within an asymmetric cavity an anomalous force is generated pushing the cavity towards its narrow end.

This force can be predicted to some extent using a new model for inertia that has been applied quite successfully to predict galaxy rotation and cosmic acceleration, and which assumes in this case that the inertial mass of photons is caused by Unruh radiation and these have to fit exactly between the cavity walls so that the inertial mass is greater at the wide end of the cavity. To conserve momentum the cavity is predicted to move towards its narrow end, as seen.

This model predicts the published EmDrive results fairly well with a very simple formula and suggests that the thrust can be increased by increasing the input power, Q factor, or by increasing the degree of taper in the cavity or using a dielectric.

There is information from Paul March on the testing of the controversial EMDrive at NASA Eagleworks. Paul commented on the NASA spaceflight forum.

Experimental Thrust is at 50 micronewtons but need at least 100 micronewtons to go to Glenn Research Center (GRC) for a replication effort in the next few months

The NASA Eagleworks Lab is still working on the copper frustum thruster that was reported on last summer at the AIAA/JPC. They have now confirmed that there is a thrust signature in a hard vacuum (~5.0x10^-6 Torr) in both the forward direction, (approx. +50 micro-Newton (uN) with 50W at 1,937.115 MHz), and the reversed direction, (up to -16uN with a failing RF amp), when the thruster is rotated 180 degrees on the torque pendulum. However they continue to fight through RF amplifier failures brought on by having to operate them in a hard vacuum with few $$$ resources to fix them when they break, so the desired data is coming along very slowly. They are still working on obtaining enough data though that will allow us to go to Glenn Research Center (GRC) for a replication effort in the next few months. However that will only happen if they can make the thrust signature large enough since the GRC thrust stand can only measure down to ~50uN, so we have to get the thrust signature up to at least 100uN before they can go to GRC.

Seven months ago there was the big splash from the EMdrive and Cannae drive results.

The 21 page Anomalous Thrust Production from an RF Test Device Measured on a Low-Thrust Torsion Pendulum paper is online at Libertarian News.

Abstract - Anomalous Thrust Production from an RF Test Device Measured on a Low-Thrust Torsion Pendulum

This paper describes the test campaigns designed to investigate and demonstrate viability of using classical magnetoplasmadynamics to obtain a propulsive momentum transfer via the quantum vacuum virtual plasma. This paper will not address the physics of the quantum vacuum plasma thruster (QVPT), but instead will describe the recent test campaign. In addition, it contains a brief description of the supporting radio frequency (RF) field analysis, ssons learned, and potential applications of the technology to space exploration missions. During the first (Cannae) portion of the campaign, approximately 40 micronewtons of thrust were observed in an RF resonant cavity test article excited at approximately 935 megahertz and 28 watts. During the subsequent (tapered cavity) portion of the campaign, approximately 91 micronewtons of thrust were observed in an RF resonant cavity test article excited at approximately 1933 megahertz and 17 watts. Testing was performed on a low-thrust torsion pendulum that is capable of detecting force at a single-digit micronewton level. Test campaign results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma.

From the Full paper

Talk Polywell had an interesting comment on the full paper

Eagleworks tested one tapered (frustum) cavity, aka Shawyer's EmDrive; and two Cannae drives which are also asymmetric but different resonant cavities. The Cannae drive is said to work on a purported different principle than the EmDrive, according to its inventor Guido Fetta (a net Lorentz force imbalance of electrons upon top vs bottom wall of the cavity). According to this purported working principle, one Cannae drive had radial slots on its rim as required by Fetta in order to produce net thrust, and the second Cannae drive didn't have those slits and was intended to be a "null test device". But the Cannae null test article… also produced net thrust (20 to 40 µN of net thrust depending of the forward or backward direction).

The null device having thrust means that the Cannae drive theory that the slits mattered was not true. However, this is irrelevant as to whether the Cannae drive produces thrust. Another theoretical explanation is needed but the anomalous thrust remains

We're talking of net thrust because of course the setup was also tested with a null 50 ohm load connected, in order to cancel the effect from the drives and detect any detect any spurious force due to EM coupling with the whole apparatus (which exists, at 9.6 µN) and this "null" spurious force was evidently subtracted from any thrust signal due to the drives then tested on the pendulum.

All tests articles (the EmDrive version, the Cannae drive version, and even the Cannae "null test" version) had a dielectric embedded within. This is a hint for a different theoretical explanation involving EM fields, proper acceleration, mass fluctuation and dielectrics. Maybe Mach effects (due to Mach's principle), as supposed by Woodward and Fearn within the GR theory, or within a scalar-tensor theory of gravity according to Minotti.




What space missions are possible with early versions if this is true?

Based on test data and theoretical model development, the expected thrust to power for initial flight applications is expected to be in the 0.4 newton per kilowatt electric (N/kWe) range, which is about seven times higher than the current state of the art Hall thruster in use on orbit today. The following figures show the value proposition for this class of electric propulsion. A conservative 300 kilowatt solar electric propulsion roundtrip human exploration class mission to Mars/Deimos. A 90 metric ton 2 megawatt (MW) nuclear electric propulsion mission to Mars that has considerable reduction in transit times due to having a thrust to mass ratio greater than the gravitational acceleration of the Sun (0.6 milli-g’s at 1 AU). The same spacecraft mass performing a roundtrip mission to the Saturn system spending over a year around two moons of interest, Titan and Enceladus. Even in this last class of mission which requires only a single heavy lift launch vehicle, the mission has less mission duration than is common with a current conjunction-class Mars mission using chemical propulsion systems and which would require multiple heavy lift launch vehicles. 300 kW SEP Roundtrip Mission to Mars Deimos (50 day stay) departing from DRO 300 kW SEP



SOURCES - Physics from the Edge, Progress in Physics

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