Berkeley CSUA MOTD:Entry 34011
Berkeley CSUA MOTD
2019/04/22 [General] UID:1000 Activity:popular

2004/10/9-11 [Science/GlobalWarming, Science/Physics] UID:34011 Activity:nil
10/9    Regarding that Dyson dude on TV with the vacuum that doesn't lose
        suction- what's the technology that keeps the dirt away from the
        \_ Well I wrote a well thought-out reply but some douchebag overwrote
           it.  I was sort of right in that there can be no bag and that
           airflow causing the dust to settle might be the mechanism.  A little
           googling produced:
           So the airflow is designed to increase centrifugal force and stick
           the dirt to the side of the cannister.
2019/04/22 [General] UID:1000 Activity:popular

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James Dyson - Inventor and entrepreneur How does a Dyson work? All vacuum cleaners contain a fan which sets up a powerful stream of air in the opposite direction to the way you are using the machine. This air is then expelled through an outlet which is generally at the front of t he cleaner above the head. Without the outlet the machine would expand a nd blow up as it continually filled with sucked-in air! This air also contains the dust and debris that was lodged in your carpet . Obviously, this cannot be allowed to escape with the air or you would merely be showering the dust back into your room. A traditional vacuum cleaner does this with the ai d of a cloth or paper bag. The air is sucked into the bag, passes throug h it and the dust is caught and left behind. As the bag gets fuller, the air has more dificulty getting through the bag, and the pores of the bag get progressively blocked as well. Th is makes the cleaner far less efficient and it loses its suck. A Dyson draws the dusty air up a pipe, from where it whooshes out into th e top of a cone. As it rushes across the top of the cone and hits the th e curved edge on the opposite side, the air is deflected around the edge of the cone. There is a law of physics that shows when air hits a surfa ce and makes its first turn around a curved wall its original speed is i ncreased by three times. Now the cone shape comes into its own because as the air flies around the curved surface, each time it goes around the cone has forced it further down the sides which in turn increases the speed again and again. By th e time it reaches the bottom, the dusty air has increased its speed from 20 mph to 924mph, which is equivalent to 324,000 rph A lot faster th an the paltry 1000 rph of your washing machine on spin. Now this cyclone effect has the same effect on the dust as the old fairgr ound ride you may have tried as a child had on its riders. You stepped i nside a large ring with high walls and stood against the walls with your back to them, facing the centre of the circle. It then started to spin, steadily increasing in speed until it reached about 20mph. You in turn were pressed against the wall by the centrifugal force until you couldn' t move a muscle, wherupon the floor dropped away leaving the riders stuc k to the wall like flies on flypaper. The riders were unable to move unt il the speed dropped. In the cyclone, read dust instead of riders and you will see that the dus t, no matter how light it appears when floating about your rooms, sudden ly becomes very much heavier when these g-forces come to bear on it. Pre ssed against the outside of the cone, the dust particles drop to the bot tom and start collecting in the plastic drum of the cleaner. Well the air, having no mass and t herefore no weight is not under the same pressure as the dust and so is not being pressed agianst the walls of the cone. It merely looks for the easiest way out, which in the Dyson's case is a chimney in the centre o f the cone. Internet Holiday Villas where you can search the world for holiday vi llas, choose where you want to go and book direct with the property owne r That means you SAVE MONEY - we take no fees, no commission, nothing Search All Info About Go!