…and how about some of that famous New Yorker fact-checking? Tilley’s interest in science is noted in this delightful cover, and The New Yorker has published some excellent popular science, including environmental articles by John McPhee. But this week’s embarrassingly adulatory profile of James Dyson, which retails one technical howler after another, raises the question (given the topic, which is Dyson) whether the inventor is a complete mountebank or the author just didn’t understand what he was told.
No, John, there is no supersonic flow inside a Dyson vacuum. No, there is nothing novel about using the Bernoulli effect to use a entrain a large volume of air into low-velocity flow with a small high-velocity jet, as the “ring fan” does; every burner on every gas range and outdoor grill and lab bench does this. There is nothing new about a centrifugal air cleaner – what the Dyson vacuum is – and you can see one on the roof of any factory that has to deal with wood chips or sawdust; in fact, I have a small one in my basement, hosed up to my table saw and planer. Dyson’s version of it is indeed a very nice vacuum cleaner, but it is no more an invention than is his ballbarrow; wheelbarrows with high-flotation tires and large, useful, buckets have been around for a long time and the spherical wheel is a visual gimmick.
It goes on and on: the blather about the Dyson digital motor can only be written by someone who has no idea how many kinds of electric motors are already humming away around the world, with and without brushes, fast and slow…and no, Dyson has not “doubled the efficiency” of electric motors, which is typically way higher than 50%. [What is the sound of a 120% efficient device clapping – a vote to repeal the laws of thermodynamics?] And what is the “conventional motor” whose speed Dyson’s version triples? Grainger will sell you one anywhere from 1150 to 30,000 rpm, right off the shelf, all conventional, and a brushless electronically controlled dc motor is spinning your hard drive right now. And no, microchips don’t “transmit current” to the rotor instead of brushes, electromagnetic induction does that and has for more than a century.
Maybe The New Yorker needs to hire somewhat fewer English majors and salt the crew with a couple of people who have a nodding acquaintance with physics.