A "near silent" bladeless fan that is claimed to be quieter than a buzzing mosquito has been released by Dyson.
The British company says its new Air Multiplier fan is up to 75 per cent quieter than the original model, released in 2009, after a team of 65 Dyson engineers reduced the turbulence of high-velocity air.
The fan is the first Dyson machine to include a Helmholtz cavity in the base to eliminate tones of 1,000Hz, similar to the frequency of the noise produced by the wing beat of mosquitoes.
Dyson's engineers found that the frequency that most irritated users of its previous fans was 1,000Hz, making their goal for it to be "totally inaudible" from the new model.
A Helmholtz cavity catches soundwaves travelling through the machine. When air is forced into the Helmholtz, the pressure inside increases. These soundwaves are then bounced within the cavity, dissipating the sound and in turn improving the tone of the machine.
Company founder Sir James Dyson said: "By reducing air turbulence and using ingenious, simple engineering principles like a Helmholtz cavity, Dyson engineers have targeted tones and reduced sound volume, making quiet fans with powerful airflow."
Engineers developing the new model passed UV paint through the machine's loop to chart and optimise airflow, with the aim of reducing noise.
The bladeless fan, which has proved to be one of Dyson's most successful and profitable inventions, works by using a brushless motor in the base to draw air in and feed it into the circular tube. The air then comes out of a crack all around the ring and passes over a shape like that of an aircraft wing.
Dyson said it invested £40m into its newest fans, spending almost £1.5m every week on research and development in 2012. The various sizes of the new fan cost between £220 and £300.