The bladeless mini fan looks like an ordinary ring located on a stylish stand, and at the same time it is able to create a fairly strong air flow. At first glance, it seems that in the ring there are blades of transparent material that rotate very quickly, however, upon closer examination, it can be understood that the device does not have them at all.
The concept of this device was created by British engineer D. Dyson, who was very observant and, as a hobby, was engaged in improving technologies that already exist. He preferred to remove from the structure everything that does not work at the proper level.
The bladeless mini fan has a fairly simple principle of operation.
It functions according to the principle of a conventional atomizer: a stream of air moving at a certain speed forms a rarefied zone in the device head, where all the liquid from the tank is directed. This liquid is trapped in a stream of air, so it is sprayed. The bladeless mini-fan acts in a similar way, however, instead of liquid, an additional air volume is captured by the working stream, which moves to the rarefaction zone. This eliminates the need for blades.
The bladeless mini fan is made in the form of a hollow ring located on the stand. Inside it is a compressor station associated with a control point. The compressor is made in the form of an impeller with an electric motor that draws air through special holes made in the housing. As controls, there is a button for turning on, as well as a handle that rotates the ring horizontally, and a speed control. In the vertical plane, the ring can only be tilted with your hands. Some models may have a remote control, as well as a spring-loaded stand that allows you to adjust the height of the device.
The desktop mini-fan, like other models of bladeless devices, is quite simple in terms of the device. The ring is an aerodynamic profile having the shape of an airplane wing in cross section. The end face of the ring is equipped with an opening for air inlet. Different models have a hole of different widths (within 1.5-3 millimeters). The closed space in the ring allows you to create an excess of pressure, the value of which depends on how fast the air will go out, as well as on the number of revolutions of the engine.
It turns out that the faster the air comes out, the larger the rarefied zone, therefore, the volume of trapped air increases. In such a design, the functions of the amplifier lie on the ring, and the coefficient of action for it is 15. This means that the air flow is 15 times higher than that pumped by the compressor.
A very good option is a battery-powered mini fan. It can be installed in any convenient place, taken with you to nature, to get a little relief during the summer heat.