Are CRTs Suitable for Use in Ion Thrusters?

In summary, an ion thruster uses 2 electron guns to create a wind of ions and use that thrust to move things.
  • #1
RamSkull
1
1
Hello!

I'm trying to make a simple ion thruster that will be used in a science fair so I'm not concerned about its efficiency but just creating at least some thrust. However I wanted to make it as close as reality as possible, using every component and respecting its details if possib
electron-gun-2.jpg
le.


Ion thrusters use 2 electron guns, and this is when I came across those electron guns used in CRTs inside old monitors and televisions. However, I don't know if they are suitable for this task. If not, are there another alternatives for the electron guns?

Thanks!
 
Physics news on Phys.org
  • #2
That sounds very ambitious and exciting. I hope you succeed.

Ions are much more massive than electrons. An electron gun is not an ion gun, so don't confuse the two.

A Google search for DIY ion thruster finds many hits. However, most of those are not useful. One that does sound real is this

https://www.popularmechanics.com/mi...-fair-experiment-to-aircraft-engine-15326499/
and

http://lae.mit.edu/2013/04/03/ehd/
In those cases, the device did not try to levitate itself, but rather to create a wind of ionized air. The wind current could make some bits of paper move to demonstrate nonzero thrust.

So, first see if you can understand those articles. Then, I would recommend that you try to contact the MIT professor Steven Barrett mentioned in the article and talk to him about doing it as a science fair project.

However, be aware that even that project requires some high voltages. You can do that safely only with the supervision of a mentor or adviser with you face-to-face, not by asking strangers on the Internet. We do not discuss dangerous topics on PF, so if this thread goes in a dangerous direction, we may have to close it.
 
  • Like
  • Wow
Likes pinball1970, RamSkull, Rive and 1 other person
  • #3
Try google up 'arc thruster'. I think that's DIY-able, without much vacuum involved.
 
  • Like
Likes RamSkull
  • #4
One could simulate thrusters, even build a scale model depending on the rules and education level of the science fair.

Radiometers are evacuated glass bulbs with a rotor with four vanes mounted on a spindle. Each vane has a dark absorbing side and a white or silver reflecting side.

Simulate the ion engines with a device that emits infrared (IR) and/or visible light. Not sure if CRTs are the proper device. Perhaps you could rig an IR source. A carbon rod arc-light with an IR filter certainly works but may be over-kill and requires adult supervision. Would laser pointers work?

Aim your simulated engine at the radiometer to simulate thrust by spinning the rotor.

1564509833283.png


For extra credit the OP could explain how Crookes radiometers work.
 
  • Like
Likes RamSkull
  • #5
Does it make sense just to make an air-breathing electric engine using MHD? Your ion engines are not working in a vacuum chamber by the way
 

1. What is a CRT?

A CRT, or cathode ray tube, is a type of vacuum tube used in older television sets and computer monitors. It contains an electron gun that produces a beam of electrons, which are then directed onto a fluorescent screen to create an image.

2. How do ion thrusters work?

Ion thrusters use electricity to accelerate ions (charged particles) out of a nozzle at high speeds, creating thrust. This thrust is much lower than that of traditional chemical rockets, but it can be sustained for long periods of time, making it ideal for deep space missions.

3. Are CRTs suitable for use in ion thrusters?

Yes, CRTs can be used in ion thrusters as electron guns. However, they are not commonly used due to their large size and weight compared to modern electron emitters, such as field emission cathodes.

4. What are the benefits of using CRTs in ion thrusters?

Using CRTs as electron guns in ion thrusters allows for a simpler and more cost-effective design, as they are readily available and do not require complex manufacturing processes. They also have a longer lifespan compared to other electron emitters.

5. Are there any drawbacks to using CRTs in ion thrusters?

As mentioned before, CRTs are larger and heavier than other electron emitters, which can affect the overall weight and efficiency of the ion thruster. They also require a high voltage power supply, which can be challenging to maintain in space environments.

Similar threads

  • Electrical Engineering
Replies
30
Views
2K
  • STEM Educators and Teaching
2
Replies
40
Views
2K
  • Electrical Engineering
Replies
2
Views
2K
  • Aerospace Engineering
2
Replies
35
Views
3K
  • High Energy, Nuclear, Particle Physics
Replies
2
Views
990
  • General Engineering
Replies
23
Views
2K
Replies
6
Views
12K
  • High Energy, Nuclear, Particle Physics
Replies
5
Views
3K
  • Aerospace Engineering
Replies
2
Views
7K
  • Biology and Medical
Replies
13
Views
2K
Back
Top