### Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 2514264 times)

#### Blaine

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3700 on: 05/18/2015 09:16 PM »
Iluian really needs to turn his device upside down.  People on the internet are getting antsy and so am I.
Weird Science!

#### txdrive

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3701 on: 05/18/2015 09:17 PM »
So your thrust is in opposite direction from EagleWorks, right?

Movement is as per Shawyer. From the big end toward the small end.
Watch the video to see which way it moves.
http://emdrive.com/dynamictests.html
As per Shawyer's theory papers, it should be moving wide end forward.

Reaction / EM Drive physical movement is in the opposite direction to Thrust direction. He has stated this many times.

http://www.emdrive.com/theorypaper9-4.pdf
Quote
The group velocity of the electromagnetic wave at the end plate of the larger
section is higher than the group velocity at the end plate of the smaller section. Thus
the radiation pressure at the larger end plate is higher that that at the smaller end plate.
The resulting force difference (F g1 -F g2 ) is multiplied by the Q of the resonant
assembly.

So, it would have to be mounted the larger plate forward if you want your ship to go forward.

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.
http://exploration.grc.nasa.gov/education/rocket/rktth1.html

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3702 on: 05/18/2015 09:18 PM »
When he makes a weight measurement, he is weighing the device plus whatever air/water vapour is inside it. Therefore when there is less air inside the device, the device will weigh less. It's as simple as that. Why should a higher temperature result in less air inside the device? - that's because the density of air depends on its temperature; it decreases with higher temperature. Since the device volume is constant and the density of air has dropped, there must be less air mass inside the device at higher temperature.
mass = density * volume.

And this is no "tiny artifact" - it's an effect on order negative half a gram, which turns out to be exactly what was measured.

He is weighing the air/water vapour inside the cavity?

How is that happening?

Those gasses / molecules are not liquid / frozen solid on the bottom of the frustum. They are bouncing around, exerting the same pressure on all sides. If you heat the water vapour, it will just bounce around faster, transferring heat to the walls and end plates. Additionally there are 2 large holes in the side of the frustum walls. Any increase of pressure inside the frustum will equalize to outside pressure very quickly, like at the speed of the vibrating gas atoms / molecules.

I will grant you that gasses trapped above the central side vent holes will reduce in pressure and will provide lift. But not gasses at or below to the hole closest to the small end.

So maybe calc the volume of air that would be trapped between the small end plate and the hole nearest the small end plate. Suggest it is a lot less air mass than you are using at present.

Did you actually look at the rate of change when the maggie drives microwaves into the cavity and not? It happens in one or 2 updates of the scale. VERY fast going UP and DOWN.

Heating the frustum will not increase nor decrease the weight measured by the scale due to the setup. Likewise vertical CG movement will not effect measured weight.
It Is Time For The EmDrive To Come Out Of The Shadows

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3703 on: 05/18/2015 09:25 PM »
So your thrust is in opposite direction from EagleWorks, right?

Movement is as per Shawyer. From the big end toward the small end.
Watch the video to see which way it moves.
http://emdrive.com/dynamictests.html
As per Shawyer's theory papers, it should be moving wide end forward.

Reaction / EM Drive physical movement is in the opposite direction to Thrust direction. He has stated this many times.

http://www.emdrive.com/theorypaper9-4.pdf
Quote
The group velocity of the electromagnetic wave at the end plate of the larger
section is higher than the group velocity at the end plate of the smaller section. Thus
the radiation pressure at the larger end plate is higher that that at the smaller end plate.
The resulting force difference (F g1 -F g2 ) is multiplied by the Q of the resonant
assembly.

So, it would have to be mounted the larger plate forward if you want your ship to go forward.

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.
http://exploration.grc.nasa.gov/education/rocket/rktth1.html

Iulian EM Drive moves in the same direction as Shawyers Demo rotary table. Toward the small end.

http://www.emdrive.com/EmDriveForceMeasurement.pdf

Shawyer shows in this diagram the direction of the Reaction, which moves the EM Drive.
« Last Edit: 05/18/2015 09:28 PM by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

#### demofsky

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3704 on: 05/18/2015 09:28 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3705 on: 05/18/2015 09:32 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Might be hard to roll into a smooth frustum.

I plan to drill 6 x 1mm diameter equally spaced holes 5mm in from each end of the frustum and the same around the central diameter to allow heated air to escape without causing any major issues.
« Last Edit: 05/18/2015 09:34 PM by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3706 on: 05/18/2015 09:36 PM »
...

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.

Propellant comes out of a rocket engine.  According to Shawyer nothing comes out of an EM Drive.

If nothing is coming out of the EM Drive, how can it have a thrust force in the opposite direction to its acceleration?

Has someone measured that thust force you are referring to ? If this thrust force of the EM Drive has been measured, how was the thrust force measured simultaneously with a measurement of the acceleration in the opposite direction  ?

« Last Edit: 05/18/2015 09:37 PM by Rodal »

#### PaulF

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3707 on: 05/18/2015 09:38 PM »
A couple of questions, out of curiosity:

1. Have any of the copper frustums been polished to a near perfect mirror on the inside? If not, why not? I can imagine that could have a positive effect on Q.

2. Has anyone picked up on the notion that the most efficient frustum may be a wide, short one? In other words, building one according to that model?

« Last Edit: 05/18/2015 09:40 PM by PaulF »

#### zellerium

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3708 on: 05/18/2015 09:38 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Might be hard to roll into a smooth frustum.

I plan to drill 6 x 1mm diameter holes 5mm in from each end of the frustum and the same around the central diameter to allow heated air to escape without causing any major issues.

It might be more difficult to roll a smooth frustum, but it would also cut down the cost.
Wouldn't thermal expansion be less of an issue with a perforated structure? It would allow much more convection cooling.

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3709 on: 05/18/2015 09:39 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

It should not matter to a microwave oven.  Millions of microwave ovens with glass transparent to microwaves are covered with this perforated metal to prevent the microwaves from escaping the microwave open and hurting humans.

At least the small and big flat ends could be made of perforated metal.

The opening in the mesh is equivalent to a very small wavelength.  I haven't seen a paper supporting that such a small wavelength is responsible for the EM Drive thrust.

« Last Edit: 05/18/2015 09:47 PM by Rodal »

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3710 on: 05/18/2015 09:40 PM »
...

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.

Propellant comes out of a rocket engine.  According to Shawyer nothing comes out of an EM Drive.

If nothing is coming out of the EM Drive, how can it have a thrust force in the opposite direction to its acceleration?

Has someone measured that thust force you are referring to ? If this thrust force of the EM Drive has been measured, how was the thrust force measured simultaneously with a measurement of the acceleration in the opposite direction  ?

As you well know it was measured and reported here:

4th line. Measured on the rotary test rig as the Demonstrator EM Drive moved.
« Last Edit: 05/18/2015 09:43 PM by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

#### demofsky

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3711 on: 05/18/2015 09:42 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Might be hard to roll into a smooth frustum.

I plan to drill 6 x 1mm diameter equally spaced holes 5mm in from each end of the frustum and the same around the central diameter to allow heated air to escape without causing any major issues.

Hm.  I can see folks being more comfortable with holes around the central diameter.  Holes at either end could result in debates over whether this was causing thrust towards one end or the other, biasing the results...

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3712 on: 05/18/2015 09:43 PM »
...

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.

Propellant comes out of a rocket engine.  According to Shawyer nothing comes out of an EM Drive.

If nothing is coming out of the EM Drive, how can it have a thrust force in the opposite direction to its acceleration?

Has someone measured that thust force you are referring to ? If this thrust force of the EM Drive has been measured, how was the thrust force measured simultaneously with a measurement of the acceleration in the opposite direction  ?

As you well know it was measured and reported here:
No, I don't know that.

I see a chart that Shawyer put together.  Nobody here could explain why the Demo Engine has it in both directions.

I never saw a paper detailing how such a thrust was measured simultaneously with measuring the acceleration in the opposite direction.

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3713 on: 05/18/2015 09:47 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Might be hard to roll into a smooth frustum.

I plan to drill 6 x 1mm diameter equally spaced holes 5mm in from each end of the frustum and the same around the central diameter to allow heated air to escape without causing any major issues.

Hm.  I can see folks being more comfortable with holes around the central diameter.  Holes at either end could result in debates over whether this was causing thrust towards one end or the other, biasing the results...

Holes would be in the side walls, not in the end plates. Hard to see how 6 x 1mm diameter holes even spaced around the ends of the frustum could generate significant thrust.

Easy to block and unblock during different test runs.
It Is Time For The EmDrive To Come Out Of The Shadows

#### demofsky

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3714 on: 05/18/2015 09:54 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

It should not matter.  Millions of microwave ovens with glass transparent to microwaves are covered with this perforated metal to prevent the microwaves from escaping the microwave open and hurting humans.

At least the small and big flat ends could be made of perforated metal.

The opening in the mesh is equivalent to a very small wavelength.

That is my understanding as well.  But what about surface effects that may be happening?  Ultimately there is some type of coupling happening with the interior fulstrum surface or folks really are creating little warp drives.

Either this is purely a type of microwave phenomena as Sawyer, et al believe, in which case it really is all about Q or there is some other (secondary) effect that is causing thrust...

#### tchernik

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3715 on: 05/18/2015 09:54 PM »
...

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.

Propellant comes out of a rocket engine.  According to Shawyer nothing comes out of an EM Drive.

If nothing is coming out of the EM Drive, how can it have a thrust force in the opposite direction to its acceleration?

Has someone measured that thust force you are referring to ? If this thrust force of the EM Drive has been measured, how was the thrust force measured simultaneously with a measurement of the acceleration in the opposite direction  ?

Yep. Force of what kind? can it be measured? felt? what medium carries it?

If we have no proper answer to this, just drop it.

Let us just content ourselves with proving if the device actually accelerates along a vector going from the big to the small end's direction when powered on, or not.

This point of the pseudo-force/reaction has really baffled me since I started reading about this, and it is very likely due to Roger Shawyer's own flaky explanation of his potential invention/discovery.

#### demofsky

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3716 on: 05/18/2015 09:57 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Might be hard to roll into a smooth frustum.

I plan to drill 6 x 1mm diameter equally spaced holes 5mm in from each end of the frustum and the same around the central diameter to allow heated air to escape without causing any major issues.

Hm.  I can see folks being more comfortable with holes around the central diameter.  Holes at either end could result in debates over whether this was causing thrust towards one end or the other, biasing the results...

Holes would be in the side walls, not in the end plates. Hard to see how 6 x 1mm diameter holes even spaced around the ends of the frustum could generate significant thrust.

Easy to block and unblock during different test runs.

Yes, blocking and unblocking the holes should be sufficient.

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3717 on: 05/18/2015 09:58 PM »
...

Spacecraft move in the opposite direction to the thrust of the engine. EM Drive is no different.

Propellant comes out of a rocket engine.  According to Shawyer nothing comes out of an EM Drive.

If nothing is coming out of the EM Drive, how can it have a thrust force in the opposite direction to its acceleration?

Has someone measured that thust force you are referring to ? If this thrust force of the EM Drive has been measured, how was the thrust force measured simultaneously with a measurement of the acceleration in the opposite direction  ?

As you well know it was measured and reported here:
No, I don't know that.

I see a chart that Shawyer put together.  Nobody here could explain why the Demo Engine has it in both directions.

I never saw a paper detailing how such a thrust was measured simultaneously with measuring the acceleration in the opposite direction.

Shawyer is in business to sell licenses, not to give it all away so any DIY guy can replicate and go into business against SPR and it's clients.

There are holes in what he has put in the public domain. I doubt he has any intention of filling them in. For guys like me, working to replicate the EM Drive, we need to learn to follow the bread crumb trail he has left. For me, that trail is strong and delivering good intel.

I'm highly confident of replicating his Flight Thruster and getting close to his results.
It Is Time For The EmDrive To Come Out Of The Shadows

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3718 on: 05/18/2015 10:19 PM »
...

Shawyer is in business to sell licenses, not to give it all away so any DIY guy can replicate and go into business against SPR and it's clients.

There are holes in what he has put in the public domain. I doubt he has any intention of filling them in. For guys like me, working to replicate the EM Drive, we need to learn to follow the bread crumb trail he has left. For me, that trail is strong and delivering good intel.

I'm highly confident of replicating his Flight Thruster and getting close to his results.

Shawyer has patents granted on the  EM Drive.  One of the fundamental agreements and understanding under which patents are conferred by a state (or the European Union) to an inventor is that the inventor must disclose all the  "information material to patentability." See: Duty to disclose information material to patentability.

In intellectual property one always has to make a choice: trade secret (like the Coca Cola formula) or patent.

Under trade secret you run the risk that the secret may become public (by independent discovery), but as long as it is a trade secret it has no expiration.

A patent gives you a state-conferred monopoly, but it has an expiration date.  The state gets to make the patent information public in exchange for conferring the patent's monopoly to the inventor.

I'm sure that Shawyer would disagree with your statement if you are referring to information material to patentability protected by Shawyer's patents.

On the other hand, if you are not referring to information material to patentability, then the information you are referring to "so any DIY guy can replicate and go into business" is not protected by Shawyer's patents.
« Last Edit: 05/19/2015 01:39 AM by Rodal »

#### rfmwguy

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##### Re: EM Drive Developments - related to space flight applications - Thread 2
« Reply #3719 on: 05/18/2015 10:20 PM »
So should everyone be using perforated copper sheeting??  Admittedly, I can't even begin to imagine how this would affect the performance of the drive.  Do the various theories need a solid wall or as long as the perforations are sufficiently fine it should not matter??

https://concordsheetmetal.com/store/perforated-copper/

Good thoughts as the mesh would be a cost-effective solution for trials, however, its likely going to be a lower Q which theoretically inhibit power/effeciency. My old company used this exact material in an impedance matching network, while a competitor used solid aluminum. At the end of the day, the 50 ohm freq matching was extended abt 25% by using the more expensive solid cone. I'd suggest initial proof of performance testing on the mesh, moving up to silver-plated flash over copper.

Another topic I have not see discussed is intermodulation products caused by dissimilar metals, perhaps nickel( Magnetic)-plating of connectors and such. I'm not sure if IM products would adversly affect the trials, as the magnetron is inherently spraying out bits all over the spectrum.

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