In the eye of the vortex that keeps Dyson’s world spinning
Behind all of the technological advancements made by Dyson in the past 25 years, the cyclone is the one central phenomenon that has remained at the heart of almost everything they do. While electrical motors power almost all their machines, it’s the cyclone that is in their devices’ DNA. Before you can understand where Dyson’s new technologies come from, first you need to know the history of Dyson’s very own double helix…
Imagine a tornado ripping through the American Midwest. Air is rushing in a spiral and being pushed into a cone shape. Everything in its way is being sucked up into the vortex, from road signs to barn doors — perhaps even the occasional cow. Once lifted into the spiral all the debris is spun at speeds of up to 300mph. This is the point when something quite interesting happens which involves fluid dynamics, advanced geometry, particle science and a heck of a lot of G-force.
As the rubble is inhaled by the tornado it joins the spiralling column of wind. So long as an object weighs less than the centrifugal force trying to fling it out of the funnel, it will keep spinning round and round. Anyone who has played with a Scalextric car racing toy will have a good understanding of this phenomenon. If you are pushing your car too fast into the corners eventually it will fly off in the bend.
Observing the devestation left in the wake of a weather cyclone, it wouldn’t have been surprising if the inventor who first decided to harness this phenomenon wanted it for weapons of war. Luckily, he had a more domestic purpose in mind.
The first “cyclonic separator” was patented in 1885 by the American John M. Finch, for use as a “dust collector” in his Knickerbocker Company.
During the 1900s, this technology found wide industrial appeal by offering large scale separation in factories or mills. Another American inventor, O. M. Morse, was awarded a similar patent in 1905 for a new “dust collector” which he developed to reduce “dust explosions” in flourmills. Despite their delicate sounding names these explosions are anything but. They essentially rapidly ignite all the untrapped particles, turning the air itself into a fireball.
“The very first ‘cyclonic separator’ was patented in 1885 by the American John M. Finch, for use as a ‘dust collector’ in his Knickerbocker Company.”
In 1878 the seven-story Washburn A Mill in Wisconsin, the largest mill in the world at the time, suffered just such an explosion. It was so massive that it was actually heard 10 miles away and killed 18 workers — not to mention reducing the mill and several neighbouring factories to cinders.
Consequentially, by the 20s the separators were being used on a larger scale than ever before, including in oil refineries where they separated oils and gases, or in sewage treatment plants where adapted ‘hydroclones’ removed solid waste from liquids.
But in the past 25 years the cyclone has arguably become a much larger part of people’s everyday lives simply by getting smaller.
Cyclonic separators were shrunk enough to be used in household appliances for the first time with Sir James Dyson’s invention of the bag-less vacuum cleaner. The idea of putting a cyclone in a vacuum cleaner came after he saw an industrial sawmill at the Bath branch of timber importers, Hill Leigh Ltd. Although this company was liquidated in August 2012, it was bought by Travis Perkins Builders Merchants who still maintain a working sawmill on the site to this day.
Sir James described this moment of inspiration in an interview with the Guardian in 2016:
“One day I was at a local sawmill and noticed how the sawdust was being removed from the air by large industrial cyclones. My engineering instinct kicked in. Could that work on a smaller scale? So I created a cardboard prototype and strapped it on to my machine. It didn’t look great, but it picked up more dust.”
His first commercial use of the cyclonic technology was G-Force, which was licensed to the Japanese company Apex Inc. in 1983. It was only sold in Japan.
By 1993 Dyson had launched its first product, DA001. This was quickly changed to the now much better known DC01 which started the naming tradition of “Dyson Cyclone” before the project’s version number which has ontinued up to this day with the latest Dyson Cyclone V10.
In the decade between 1997 and 2007, Dyson created 16 versions of their cyclonic technology starting with the invention of their second upright vacuum cleaner DC03. By 2017 the number of “Dyson Cyclone” named projects had reached DC62.
Dyson’s Design Director, Alex Knox, was there at the very beginning. When he first joined Dyson 25 years ago the cyclone was still in its infancy and the company was operating out of a coach house in Chippenham.
“There were no tests for the efficiency at the time because Sir James invented it,” says Alex. “The test was trying it and seeing how well it worked. We’d just keep chucking stuff in and redesigning it until it worked well enough that we were happy with the results.”
Times have changed. “I think we understand the fundamentals of the cyclone incredibly well . Now the challenge for us, knowing the limitations as we do, is to ask ourselves: ‘how do we move to the next step?’”
The single biggest leap in Dyson’s cyclonic technology in the past 25 years was undoubtedly the replacement of one big cyclone with lots of little cones.
“I don’t know where [the engineers] got the inspiration from for that,” Alex says, “but the development of the frusto-conical, ‘Root Cyclone’ was a game-changer.”
He continues, “we found if you had multiple small cones you could maintain the efficiency of one big cone, but it consumed less power. There is a mathematical equation that means each one of those smaller cones, geometry-wise, is scaled.”This enabled their cyclones to work harder while consuming less power which ultimately led to the development of handheld vacuums, like their DC16 in 2007.
This is where the story turns back on itself like the cyclone. While the first cyclone necessitated the development of other technologies to help make itself more efficient, today it’s the batteries and motors that are dictating the terms of design to the cyclone.
At the global launch of Dyson’s latest product in March 2018, Sir James Dyson claimed that their latest handheld vacuum was so efficient that his company would no longer be developing corded vacuum technology. Essentially the other contributing technologies had finally made the handheld cyclone efficient enough to allow for the same standard of suction as can be seen in their corded cousins.
As a result, efficiency has arguably never been as important to Dyson as is today. With their latest vacuum, “everything about the device is linked to iterative performance improvements,” explains Charlie Park, head of product development for Dyson’s floor care products. “It’s not all about the cyclone but that’s a big part of it.”
“We’ve got a new motor, which is more efficient, it’s lighter, it’s more powerful. The same with the batteries. We’ve got more efficient, better, more powerful battery cells. And, so we’ve got a better, more efficient cyclone to separate dust, but it is all iterative.”
“Back in the day, you’d just stick in a motor, and you suck energy out of the wall,” he says. “With the handheld cyclone technology, it’s really important that we’re trying to use the limited energy that we can store in the batteries as efficiently as possible, because, if you’re not, your run times are going to be really short, and you’re going to be having to recharge it the whole time. The cyclone technology is more important than ever because we don’t want machines clogging up, and dropping off in performance.”
Despite all of their expertise, according to Alex and Charlie, when it comes to explaining the hidden significance of cyclones, there is one person at Dyson who knows it all. With a knowing smile Alex advises: “you’ll have to ask Dyson’s cyclone expert.”
He is referring to Dr Ricardo Gomiciaga, a principle engineer who has spent almost his entire career at Dyson refining and researching cyclones. When it comes to cyclones at Dyson, Ricardo’s the Godfather.
Before joining Dyson, Ricardo was conducting post-doctoral research at the University of Bath specialising in fluid dynamics, specifically: “developing computational fluid dynamics (CFD) simulations of fluid-induced forces in rotating systems not dissimilar to the physics found in cyclones.”
“At the time a lot of people joined Dyson from academia. A friend and former colleague of mine joined Dyson from my university and asked me to join him to help ‘put more academic knowledge into Dyson,’ so that’s what I did,” Ricardo says.
“When I arrived there wasn’t too much left to do to make the cyclone more efficient,” he says, “James had done a very good job without all the lab equipment just by observing and testing and redesigning.”
He spent the next 20 years monitoring and adapting the Dyson’s cyclones.
“I think it makes my case pretty unique in Dyson to have only worked on one ‘thing’ from the beginning.”
But there is a good reason for this focus. Cyclones, as it turns out, are rather more chaotic than the neat sounding name “dust separator” implies.
“I deal with machines that spin air at over 200 mph” he explains, “there is over 250,000 G-force being generated by the air. Containing this, and making it efficient at the same time, is a balancing act. And then you add multiple cyclones, all working together, now that is really about balance.”
“I enjoy cyclones. It is a simple as that,” says Ricardo “they are fascinating three-dimensional, elegant structures that can separate microscopic particles despite the high intensity levels of turbulence, time dependency and asymmetrical flow conditions.
“In a cyclone system if one portion isn’t working, none of it will. That is the point about imbalance. It is like a philharmonic orchestra; to create beautiful music everyone has to play the same tune and in a cyclone system, air spinning that fast has to be controlled to stay ordered. Even if you are a tiny fraction out in one measurement the whole cyclone could spiral out of control.”
Consequentially, a complex set of geometric equations govern the dimensions of Dyson’s cyclone. Ricardo actually has a spreadsheet calculator which is full of adjustable boxes to input angles, lengths and diameters at will. It might not look like much, but it is Dyson’s ‘cyclonic Bible’.
“There are as many parameters as you care to define but eight of them are enough to shape every cyclone. They include everything from the angle of the cone to the size and shape of the opening through which a motor forces air. Certain numbers the team can’t change, others they can, but you have to be careful what you change.”
Looking back at the 130-year history of cyclones, Ricardo’s statement certainly seems to ring true for the phenomenon more generally. From devastating natural tornado funnels to mill demolishing ‘dust explosions’, to the perfectly balanced vacuum ‘dust separators’ of the modern era, the science of cyclones is an ongoing battle between chaos and order, speed and calm, balance and inequality.
This article was originally published in on:Revolutions in May 2018.
