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Would this work to decrease air resistance in sports cars?

  1. Feb 2, 2016 #1
    Okay so here is my idea, not really sure how well (if at all) it would work but im wondering if it would be possible (assuming battery technology is good enough) to ionise air in front of a formula 1 car (or plane or whatever) giving it a charge (like the way lightning works) , then creating an opposite charge on struts projecting out to the side of the car. This would pull particles in the air out of the way of the car, and create lower air resistance.

    The only real issue I can see is the weight the battery would add with current technology, but I really want to know if there isa anything wrong with the concept?

    Tell me what you think...

    ps i'm only taking a level so i'm no expert and i'm sure there are flaws in my idea
     
  2. jcsd
  3. Feb 2, 2016 #2
    You still have to move the air out of the way. If it is done through electrostatic means or by physical contact will likely make little difference.

    The idea you are talking about would require energy and add weight. I suspect that energy would be better spent on propulsion if the objective is speed. If the objective is efficiency then the weight would be better spent on increased KERS capacity.
     
  4. Feb 2, 2016 #3
    but ignoring the weight, in theory it would work?
     
  5. Feb 2, 2016 #4

    russ_watters

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    There'should two kinds of drag: skin friction and pressure drag. Pressure drag is "moving the air out of the way". It depends on the speed and mass flow rate (momentum) of the air. Since you can't change either with this, you can'think reduce that drag.

    Skin friction drag is exactly what it sounds like. If you move the air away from the skin, you might succeed in reducing that, but probably at the expense of pressure drag due to moving the air out of the way more.

    Overall, it would be a lot of effort for little benefit.
     
  6. Feb 2, 2016 #5
    but if the air is being moved out of the way by something else and not the car then there would be less pressure drag. and if there is a lower pressure in front of the car and less particles then there would be less skin friction drag. Am i right or misunderstanding?
     
  7. Feb 2, 2016 #6

    jbriggs444

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    If you move the air out of the way by something else (for instance the walls of a subway tunnel that has been pumped out so that it now contains a vacuum) then yes, that's a pure win for the car.

    If you move the air out of the way by means of a mechanism mounted on the car then there is no free lunch. By Newton's third law, any momentum you transfer to move the air out of the way manifests as drag on the car.
     
  8. Feb 2, 2016 #7
    but all you are doing is transferring a charge, does that transfer momentum?
     
  9. Feb 2, 2016 #8

    sophiecentaur

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    That involves Work, which is not free.
    There are some ways of reducing friction for motion through fluids - the ripples on a dolphin's skin are thought to help its efficiency through the water- so it probably can't be totally discounted out of hand. It would be necessary to come up with a specific design of surface and for tests to be made.
     
    Last edited: Feb 2, 2016
  10. Feb 2, 2016 #9

    russ_watters

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    But you aren't: you are doing that in order to apply a force to the air.
     
  11. Feb 2, 2016 #10
  12. Feb 2, 2016 #11
    You are most likely referring to an Air resistance reducer^
    See Patent US 20050230525 A1
    A craft can navigate through a magnetically curved space provided by an electromagnetically charged hull. The hull contains a plurality of sectionalized and independent electromagnetic plates forming portions of the hull exterior wall that can be adaptively energized to have a desired polarity. When combined together, these sectionalized plates can provide an ultra high frequency electromagnetic field of a strength that can magnetically curve the space around the craft. This enables the craft to expeditiously travel through air, space or water.
    Very High voltages in the range of Millions of volts, would be required to generate this type of field....
    so the answer for now is no!
    Thanks,
     
  13. Feb 2, 2016 #12
    that was exactly what i was thinking of. Sad that its already patented though, i was hoping this would make me a millionaire :(
     
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