How to maximize the efficiency of the corona discharge generator

[Christofer Br]

Hi, I have a wirmhurst electrostatic generator and I want to use it to create a corona discharge. My common sense tells me that the metal "shaft", which connects to the metal spheres should lead to significant (electron) leak, since it has a much smaller radius of curvature than said spheres. If I removed those spheres, would the corona discharge still be present mainly at the "tip" of the conducting part and would it be stronger, or are those metal spheres actually helping to concentrate the corona discharge in one spot?

Also, how to know which of the two conductor parts will be nagetively charged?

 

[anorlunda]

I'm sorry you didn't attract any answers.

If I removed those spheres, would the corona discharge still be present mainly at the "tip" of the conducting part

I believe that the answers to that is, "Yes"

would it be stronger,

No.

But I do not have references or calculations to support those answers. They are just educated guesses.

 

[Tom.G]

To expand on the correct responses from @anorlunda:

If I removed those spheres, would the corona discharge still be present mainly at the "tip" of the conducting part and would it be stronger

As you are aware, the most discharge will be at spots of high curvature. This is because the strength of the electric field is higher there. The ball electrodes are used to keep the electric field lower so enough voltage can build up to jump the spark gap. Since you are after a corona discharge, replace the balls with a sharp point; you could even just tape a sewing needle to the existing balls!

As for the corona discharger being "stronger", that depends on how you define stronger. The voltage will be lower but the current density will be higher, that is the current will be concentrated at the tip of the needles. If you want a higher current, try spinning the Wimshurst disks faster.

Also, how to know which of the two conductor parts will be nagetively charged?

You can use a Neon lamp to test polarity, one of those $5 electrical testers to check if a wall outlet has power would work. A Neon lamp is sometimes called a "negative glow lamp." It is a glass enclosure with a wire brought out from each of two electrodes, and the enclosure is filled with Neon gas and sealed. When a DC voltage is applied the Neon gas will glow at the Negative electrode. Also, the video below shows (at 9:06) how to get a Wimshurst "started" or "charged", this approach may enable you to set the desired polarity.

NEON TESTER

157 000 hits found with: https://www.google.com/search?&q=wimshurst+machine

A rather detailed explanation:


Cheers,
Tom

 

[RITESHH KAKKAR]

Hello
What is Corona how it work

 

[anorlunda]

Hello
What is Corona how it work

For simple questions like that, Wikipedia is your friend.

https://en.wikipedia.org/wiki/Corona_discharge

 

[RITESHH KAKKAR]

Hello
How to watch corona in real life on wire

 

[anorlunda]

Hello
How to watch corona in real life on wire

That's a very good question. If you have a high voltage (such as 500KV) power transmission line near you, go out on a dark night and watch.

Also, search for "corona discharge" on Youtube. There are several videos.

 

[RITESHH KAKKAR]

Hello
Is it seen by Camera or simple eyes