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View Diary: The Willamette Falls Locks closed for good after 138 years (120 comments)

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  •  Interesting. I'm not sure of all the numbers (2+ / 0-)
    Recommended by:
    ozsea1, Lujane

    but you'd need some amazingly low friction bearings to match the friction of water. But you're right, at the same speed water has a greater drag than air. So if you need to get something moved quickly with low energy it isn't your best choice. Another advantage the canal system had was there were no hills on the canal, one hill in the road can annihilate any advantage of drag. Thanks for making me think about this more.

    Compassionate Conservatism is letting all the bridges collapse so you won't have to live under one after losing your home when they cut off your unemployment insurance.

    by ontheleftcoast on Fri Dec 09, 2011 at 10:12:55 AM PST

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    •  I know this subject . (5+ / 0-)
      but you'd need some amazingly low friction bearings to match the friction of water.
      Not so . You are not seeing the bigger picture . Water is not "slick" because you need to push through it .

      Take a ten pound toy car with normal bearings , push it as hard as you can , give it one big shove down a flat hard road .
      Take a ten pound toy boat , push it as hard as you can , give it one big shove down a smooth bit of water .

      How far does the toy car go ?
      How far does the toy boat go ?

      Take a one hundred horse power motor
      put in into a car , how fast can you go on land ?
      Take that same one hundred horse power motor
      and put it into a boat , how fast can you go ?

      Put 10 gallons of fuel in the car and drive it at 100 hp , how far do you get before the fuel runs out ?

      Put 10 gallons of fuel in the boat and drive it at 100 hp , how far do you get before the fuel runs out ?

      Why is it that if I drive my boat on the trailer 1000 miles
      I burn far less gas than I would if I were to run the boat alone for 1000 miles ?
      Why is it that I can drive my boat on the trailer faster the 1000 miles and burn less gas than if I were to just use the boat alone at a far slower speed on the water ?

      I can hook up my boat and trailer to my tow vehicle and go farther faster with less fuel . Why is that ?

      With 250 hp my car can go 160ish mph .
      With 250 hp my boat can go 30ish mph .  

      "Drop the name-calling." Meteor Blades 2/4/11

      by indycam on Fri Dec 09, 2011 at 10:41:23 AM PST

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      •  Your boat can't go as fast mostly because (1+ / 0-)
        Recommended by:
        Cartoon Peril

        it can't push the water as effectively as the tires can impart the energy to the road. Another aspect of the low friction of water.

        And the initial acceleration of a huge shove of a boat versus the shove on a toy car is a bogus comparison. The wake you create is consuming a huge amount of the energy.

        Actually, I think the winning combination is a small motor on land hauling cargo on water (the mule example). Because the hard flat surface you're looking for in cargo transport is a myth (like the frictionless, weightless pulleys in Physics classes) where a flat canal is sort of "by design" with water seeking it's own level and all that.

        Compassionate Conservatism is letting all the bridges collapse so you won't have to live under one after losing your home when they cut off your unemployment insurance.

        by ontheleftcoast on Fri Dec 09, 2011 at 10:47:01 AM PST

        [ Parent ]

        •  ... (1+ / 0-)
          Recommended by:
          FarWestGirl
          Your boat can't go as fast mostly because
          it can't push the water as effectively as the tires can impart the energy to the road.
          Nope that's not what is going on .
          160ish mph vs 30ish mph . That's not a prop problem .
          Props that "slip" in water cavitate and cavitation ruins the prop . A properly selected prop had great grip on the water and can transmit the engine hp to the water .
          And the initial acceleration of a huge shove of a boat versus the shove on a toy car is a bogus comparison. The wake you create is consuming a huge amount of the energy.
          Its not bogus , its reality . You put the same energy into pushing off the car and the boat , the results are wildly different . The car travels a far greater distance . The boat with the same input comes to a stop almost instantly .
          If you wish to do it another way ,
          tow the boat and car up to the same speed ,
          the boat on a canal and the car on a road along side the canal . Once you have them up to speed , side by side , drop the tow line , how far does the car coast along vs the boat ?
          Because the hard flat surface you're looking for in cargo transport is a myth
          Its no myth , I see them everywhere I drive , roads .
          Actually, I think the winning combination is a small motor on land hauling cargo on water (the mule example).
          For any motor size , wheeled transport wins . I know this for a fact .
          If I run a 6 hp diesel powered wheeled transport I can go farther faster on less fuel then if I used that same same 6 hp diesel motor to move the same cargo on water .

          Do you know what a drag tank test is ?
          Drag tank a model boat with a 100 pound cargo ,
          drag test a model car with that same cargo .
          You will find that for the same speed the drag will be less for the car and that the amount of energy it takes to move the model boat at its hull speed can move the car at a far greater speed .

          "Drop the name-calling." Meteor Blades 2/4/11

          by indycam on Fri Dec 09, 2011 at 11:23:32 AM PST

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        •  I want 1000 lbs of cargo moved from (1+ / 0-)
          Recommended by:
          Lujane

          San Diego to Seattle  . You can move it in your boat or your truck . Please give me a quote just for the diesel . How much will you burn in the boat that has a cargo capacity of 1000 lbs ? How much fuel will you burn running a truck that has the same 1000 lbs capacity ?

          "Drop the name-calling." Meteor Blades 2/4/11

          by indycam on Fri Dec 09, 2011 at 11:44:13 AM PST

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      •  Crap (2+ / 0-)
        Recommended by:
        Cartoon Peril, indycam

        Now I have to go out and get a 10# car and a 10# boat just find out what happens.

        Frankly, I blame everything on Nixon.

        by J Orygun on Fri Dec 09, 2011 at 05:42:16 PM PST

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