Centrifugal fan: specifics of the device and principle of operation of the device

Centrifugal fan: specifics of the device and principle of operation of the device

The centrifugal fan - the unit for industrial and house use which operation principle is based on transportation of air at the expense of confection. This unit allows to clean, move air and to saturate the room with enough oxygen. Use of the fan is necessary in buildings with large number of people.

The centrifugal fan – the radial device for collecting air, its cleaning and transportation. It has been developed by the military engineer Sablukov. The invention of the fan of this type has considerably simplified air exchange in large residential and industrial buildings, in medical and educational institutions. Thanks to the centrifugal fan of radial type which has come to replacement to axial it is possible to move quickly flows of air and gas, including dangerous, even in huge spaces. The overview of the device has shown that it is much more effective than predecessors.

Assignment of the fan

The convection device helps to create with the building comfortable conditions for finding of people, and in case of arrangement in nursery – for plants or animals. If the ventilating unit is installed on production, its main task is to secure the person against dangerous exhausts or to create favorable environment for production of various products.

The fan performs also some more functions:

  • constantly updates air in large rooms, purifying it from the carbon dioxide which has arisen because of activity of people;
  • transports explosive and poisonous gases, protecting people and guaranteeing lack of explosions in the building;
  • quickly moves the smoke-filled air volumes, replacing their cleaned (jury-rigs);
  • regulates indoor temperature, does not allow to arise to closeness;
  • provides freshness and comfortable conditions for breath, work and rest of people.

Before emergence of centrifugal fans used axial, less effective, or natural extract. However such types of devices cannot help at emergency as insufficiently quickly move portions of air hazardous to health and gases. And natural exhaust designs have no emergency operation at all therefore in case of fire or emission of gas poisons specifics and speed of cleaning do not increase.

In other words, the centrifugal radial fan from the moment of emergence not only has simplified construction of buildings, having allowed to create more compact air shafts, but also has saved set of lives thanks to fast work at the fires.

Scope of application

Centrifugal fans are used in buildings of any types where for them special mines and sleeves are prepared. However some spheres need such installations more than others:

  • medical institutions;
  • educational institutions;
  • industrial enterprises;
  • office buildings;
  • public (trade, entertaining) centers.

The main demand for application of installation proceeds from the enterprises located in big buildings with the raised congestion of people. In medicine it is very important to use high-quality ventilation systems as the fresh air oxygenated and purified from dust – guarantee of health of respiratory system, heart and the general good health. Especially fresh air is relevant for patients of advanced age for whom closeness indoors can become fatal.

Not only elderly people, but also children need fresh air. Otherwise the young organism can incorrectly begin to develop. There can be frequent migraines, sleep disorders and other deviations from normal health. To prevent problems at kids, in children's gardens, schools, preschool educational and leisure institutions surely establish ventilation devices.

Office and shopping malls demand the special systems of convection, movement and cleaning of air because of big congestion of people. If not to replace the "fulfilled" mass of air with big percent of carbon dioxide with fresh, then visitors of the center or office complex can have problems with health and breath.

Industrial buildings, warehouses, hangars need competent ventilation because of several factors at once:

  • streams of fresh air maintain comfortable temperature where special regulatory systems are not installed (hangars, warehouses without heating);
  • constant cleaning of air allows to reduce concentration of dangerous exhausts, toxins and gases which are formed in the course of production of metal wares, plastic, other objects of the industry;
  • big congestions of people which working capacity directly depends on air quality indoors also often work at the industrial enterprises.

Following the results of statistical data on use of centrifugal fans it is possible to tell that they are used in any branch of public work.

Advantages of the centrifugal fan

The demand of the centrifugal device is explained by its high functional performance. Namely:

  • The main fan does not demand continuous repair as its main parts (blades, the engine, wheel, casing) practically do not adjoin with each other and are not erased.
  • The simple device of the unit allows to make repair and replacement of parts not only as fast as possible, but also at the minimum expenses of money.
  • At the correct use this type of the device serves very long, but at the same time the efficiency of the unit does not fall depending on the term of its use.
  • The system of convection of air so simple that for production of the unit large volumes of money are not necessary.
  • Ample opportunities of selection of the necessary modification.
  • Despite the simple scheme of the internal device, the device allows quickly (sometimes and with emergency speed) to move air stream.

One more feature - the special protection cover and the filter does not allow to get in the device to small mechanical particles. Thanks to it life cycle increases, the unit works steadily, but only if rules of use are followed. Products are made according to state standard specification, the probability of defects is very small.

Unit components

The centrifugal fan consists of only several combined parts, each of which has the simple mechanism of production. Main parts of the device:

  • protective casing which takes away the excess particles and big mechanical elements capable to damage blades from the unit;
  • several blades (quantity depends on the unit size) which are carrying out air forcing;
  • the engine giving energy for work of all installation;
  • the wheel reporting the energy developed by the engine to blades and setting them in motion;
  • the vibrofilter reducing vibrations and noise level in space near the fan;
  • openings or knot for entrance and air outlet where there is depression.

Some parts (number of blades, openings, the unit size, complexity of filters) depends on specifics of the device. So, industrial units are equipped with more difficult filters, and house usually in general have no them. It is better to entrust selection of the device, the choice of the filter to experts.

Principle of work

The unit allows to carry out movement of air by convection. There are several steps of operation of the device. Full operating cycle:

  • Collecting air. The volume of air passes in opening for its collecting under the influence of the effect known as centripetal (it is also classified as force).
  • Forcing of air by convection. Blades, coming into action, divide air into equal portions, and each of them is exaggerated (becomes more dense) because of continuous rotation. The "squeezed" air passes into opening for release or into the filter.
  • Relevant for those units in which clearing additions are installed. Filters eliminate large mechanical particles, remove dangerous gases at the expense of difference the weight of air and gases of other structure. Gases with any quantity of molecules in structure can be eliminated and moved.
  • Production of air. The air with big pressure is let out to the area with the rarefied atmosphere. Thanks to pressure difference more "squeezed" portions move towards the rarefied spaces and are transported further on ventilation system.

Operation principle very simple, it it is possible to repeat even during creation of autographic installation. However from simplicity of the mechanism the efficiency of the unit does not fall. Besides classification of devices is extensive, and some of them contain set of additional functions.

Rules of use

At any large unit including the centrifugal fan, has rules which observance allows to increase life cycle and to reduce the frequency with which repairs are made. Any requirement of the instruction needs to be observed.

The following rules are relevant for the centrifugal fan:

  • Too many mechanical particles should not get to air duct, otherwise the filter will be constantly hammered. The maximum level of grains of sand – 1 g on air cubic meter. At the bigger volume it is necessary to change filtrational element earlier, than the term of its operation expires.
  • It is impossible that air contained the sticky particles capable to remain on blades and to lead gradually to their delay.
  • The special device which reduces vibrations has to be surely installed. It not only increases the level of comfort of people near the device, but also interferes with shaking of part of the unit.

At the correct use the device can serve up to several decades. Rather regularly to perform routine inspection and to carry out additional work package: to clean the filter, to clean air ducts.

Author: «MirrorInfo» Dream Team


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