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How do truckers feel about drafting?

Discussion in 'Gen 2 Prius Fuel Economy' started by Kinare, Apr 24, 2008.

  1. darelldd

    darelldd Prius is our Gas Guzzler

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    :p

    The envelope just says "Gasoline Bad." All other calculations are easy after that.
     
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Scr*w trucks!

    We need to start putting wireless sensors and antenna in our front and rear bumpers. The specifications should be:
    • heart-beat - so we have a positive link
    • following car steering - so the following cars track in a train
    • auto-speed control - so the following cars match the lead cars
    • auto-distance monitor - get the bumpers within 3-5 ft.
    • auto-emergency stop brake management - everyone's braking modulates to increase distance in an emergency stop
    • audio intercom - to chat and plan shifts, drops and adds
    • open source - hardware and software should be an open set of specifications. Only the vehicle interfaces would be unique.
    In a perfect world, strings of Prius (or hybrids) at 75+ mph, 3-5 ft from each other, a hybrid train, trundling down the highway in perfect sync. All will have some sort of 'blinkers' or 'signage' to let folks know we are 'on the wire.' A friendly group of hybrid owners will have one lead driver and following 'safety' drivers and we're 'making time' at 60+ MPG. Every now and then, the lead changes so everyone shares the load and the savings.

    The vehicles would have to meet the following, minimum specifications:
    • electric accelerator interface (Prius)
    • electric steering interface (Prius)
    • electric brake interface (Prius needs)
    • tire revolution sensor (Prius)
    For good measure, hybrid trains should be demonstrated at hybridfest. For good measure, it should include 'blind avoidance' so it steers around the blind or if necessary, comes to a complete stop. Furthermore, the blind transponder should give them an audio warning and bearing to the hybrid. But it should be a transponder cleverly disguised as a cell phone ...

    Bob Wilson
     
  3. qbee42

    qbee42 My other car is a boat

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    Just don't let Microsoft write the software for the hybrid trains. We could loose a bunch of PriusChatters with one blue screen.

    Tom
     
  4. Codyroo

    Codyroo Senior Member

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    Bob,

    Instead of a Prius train, wouldn't it just be simpler to mount a huge, honkin', horseshoe magnet on the top of our cars instead. Now THAT'S genius!

    BTW, I think you are tailgaing that box truck.....
     
  5. berinker

    berinker New Member

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    Re: Safe Drafting Distance?

    I totally agree with your information. I don't believe in drafting either for safety reasons but it is fun to experiment. To draft properly you must be about a car length or less behind the truck (you see trucks doing it from time to time in a convoy). Immediately behind the truck there is a reversal airflow direction that flips from side to side that will actually pull you towards the rear of the truck.
    The gas mileage can be unbelievable but, as mention before, it is dangerous. When you get beyond one or two car lengths behind a truck you will be buffeted by the whirling side to side vortices which spoil the smooth laminar flow over your car that it was designed for and your mileage will suffer. A little further back as the flow smooths out but the air is still 'somewhat' following the truck you might see a small increase but smooth undisturbed air is the best. If you can find a truck moving at higher speeds (or into a strong headwind) the effect is multiplied many times over. Be careful.
    Bud (the aerodynamic specialist).

    PS. If you wanted to 'get serious' about drafting you would mount a flat piece of plywood on the front of your car and you would be drawn up until it hit the back of the truck (laughing). When you are drafting behind a truck you are actually helping his mileage a tiny bit because your car is acting like a splitter and smoothing out the oscillating flow behind the truck, reducing drag.
    [​IMG] [​IMG] [​IMG] [​IMG]
     
  6. donee

    donee New Member

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    Hi Berinker,

    So, a way to do this operationally might be to put a wool tuft on the front of the hood. Then when behind a truck, backoff until the tuft stops flopping back and forth.
     
  7. berinker

    berinker New Member

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    Don't laugh (too hard).
    That is the way we do it on airplanes.
    When you would see the tuft(s) pointing towards the truck
    you would know that you are in the groove.
    B
     
  8. bwilson4web

    bwilson4web BMW i3 and Model 3

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    That is my tow truck ... <GRINS> It is a special Acme Inc. magnet that follows cartoon physics.

    Bob Wilson