How to choose an airless mini fan?

The bezlopastnoy mini-fan looks like an ordinary ring, located on a stylish stand, and at the same time it is able to create a sufficiently strong airflow. At first glance, it seems that there are blades of transparent material in the ring, which rotate very quickly, but with 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 design everything that functions not at the proper level. The bezlopastnoy mini-fan has a fairly simple principle of operation.

It functions on the principle of a conventional atomizer: the flow of air moving at a certain rate forms a sparse zone in the head of the device, where all the liquid from the container rushes. This fluid is captured by the flow of air, so it is sprayed. A self-winding mini-fan operates in a similar manner, but instead of working fluid, an additional air volume is captured by the working flow, which moves to the rarefaction zone. This allows you not to use the blades.

The bezlopastnoy mini-fan is made in the form of a hollow ring, located on the stand. Inside it there is a compressor station, coupled with a control point. The compressor is made in the form of an impeller with an electric motor that draws in air through special holes made in the body. As controls there is a button for turning on, as well as a handle turning the ring horizontally, and a speed regulator. In the vertical plane, the ring can only be tilted by hand. Some models may have a remote for the remote control, as well as a spring-loaded stand that allows you to adjust the device in height.

Mini-fan desktop, as well as other models of bezlopastnyh devices, is simple enough in terms of the device. The ring is an aerodynamic profile, which has a wing shape in the section. The end of the ring is provided with an opening serving to enter the air. Different models have a hole of different widths (within 1.5-3 millimeters). Closed space in the ring allows creating an excess of pressure, the value of which depends on the speed with which air will escape, and also on the number of engine revolutions.

It turns out that the higher the air velocity, the greater the rarefied zone, and therefore the volume of captured air increases. In this design, the functions of the amplifier fall on the ring, and the action coefficient for it is 15. This means that the airflow is 15 times greater than the one pumped by the compressor.

A very good option is a mini fan with batteries. It can be installed in any convenient place, take with you to nature, to get a little relief during the summer heat.