Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

DIY Van De Graaff Generator

  1. Feb 22, 2015 #1
    Ok, so I'm building a Van De Graaff generator from parts i've been collecting for some time now. I have 2 hemispherical bowls that were supposed to line up perfectly to make the ball at the top. shipping has warped them just the slightest bit. I'm wondering if this will produce coronal leakage if i just connect them how they are with aluminium tape. That's the other thing, these bowls have no brim to reduce leakage, so would you recomend that I connect them with aluminum tape or something different.
     
  2. jcsd
  3. Feb 22, 2015 #2
    this is an image of one of the bowls
     

    Attached Files:

  4. Feb 23, 2015 #3
    Doesn't have to be aluminium tape. It can be ordinary tape, but connect the domes inside with one wire/piece of a metal.
    Of course, align the domes to make sphere as perfectly as you can.
     
  5. Feb 23, 2015 #4
    zoki85, That still doesn't seem like it would solve the leakage problem. The voltage on both bowls will be the same even if they are touching the slightest bit so the wire doesn't seem like it would do much. The charge wants to move to the outside and collect until it needs to discharge. When there is an exposed edge, it will discharge into the air before it reaches its max storage potential. Do you think putting a layer of aluminum foil between the two bowls would work? Even if the layer is wrapped around the seem and then taped on.
     
  6. Feb 23, 2015 #5
    Carefully made layer of Al foil would work if it makes no protrusions.
     
  7. Feb 23, 2015 #6
    Ok thanks, Ill let you know how it works. Might have more questions pertaining to the rollers and belts.
     
  8. Feb 23, 2015 #7

    berkeman

    User Avatar

    Staff: Mentor

    It looks like you are a senior in high school. Do you have a mentor at your school or other experienced person who is helping you with this project? What is your background so far in electricity? What other projects have you built? :smile:
     
  9. Feb 23, 2015 #8
    berkeman, yes I am a senior in high school. I have a few teachers that have inspired me and occasionally answer my questions. I've built bio generators, steam engines, distillation apparatus, a vortex cannon. Currently I'm working on this generator and also approaching my third month working on "The Miller-Urey Experiment". I have a descent background in electricity. Mostly self taught from textbooks new and old. AP Physics has helped a great deal as well.
     
    Last edited: Feb 23, 2015
  10. Feb 23, 2015 #9
    Try to avoid any pointed bits and keep the surface as smooth as you can. Although the surface will be at an equipotential the electric field strength will be greater at more pointed (smaller radii) places and discharge is most likely to occur at those places. I think by far your biggest problem is in fashioning the area around the hole through which the belt passes. If you look at demonstration Van de Graaff domes you will see that the edges of this area curve inwards.
     
  11. Feb 23, 2015 #10

    berkeman

    User Avatar

    Staff: Mentor

    Good stuff. Sounds like you are on a good path forward. :smile:

    Safety is a big issue when working with high voltage. Be sure to keep safety in mind as you work your way through this project.
     
  12. Feb 23, 2015 #11

    dlgoff

    User Avatar
    Science Advisor
    Gold Member

    If the hemispheres are made of aluminum (not able to solder), make some sort of fixture to hold them in the correct position and use epoxy (use a procedure that would apply it to both parts, mostly on the inside, so it (epoxy) will run together when in fixture to cure).
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: DIY Van De Graaff Generator
Loading...