Fans Overview

What Is an Industrial Fan?

Industrial fans are generally larger, more powerful and more durable than their consumer-grade cousins. These fans are usually designed to endure harsh conditions and are made of sturdier materials than the fans found in households.

Industrial fans can be found serving several roles in their settings. They may be used to provide airflow and cooling on a factory floor, to inject air into machinery to keep it cool or to cool off computers in an office setting.

Industrial fans come in an enormous range of sizes. There are fans that have diameters of five or more feet in the case of axial fans. Other fans, such as cross flow fans and centrifugal fans may be installed directly on machinery, their sizes customize to optimize their airflow and to accommodate the size of the machinery that they are installed on.

In some cases, fans are designed in a way that allows them to handle significant airflow requirements in a compact size, such as is the case with cross flow fans. Other enhancements, such as being able to change the direction of airflow, are added to some fans.

 

How Does a Fan Function?

A fan works by way of a rotating impeller. This pushes air through the fan, causing airflow out the front.

Fans can be used to introduce air pressure into a closed environment or to lower it. For instance, computer cases are sometimes set up with negative air pressure designs and positive air pressure designs, dictated by whether the fans are blowing air through, out of or into the computer case.

Most fans have a characteristic design to them, no matter how their blades are oriented or the air that flows through them propelled.

The design of the fan does affect the function. For instance, there are significant airflow differences between how an axial fan moves air and how a cross flow fan does the same. This can affect the applications for which they are appropriate. In some cases, housings might be designed specifically to direct the airflow in a certain way and to increase the amount of pressure that the fan generates.

The basic function of a fan, however, simply involves the blades pulling air into the fan’s rotation and pushing it forward with a greater degree of pressure.

 

What Are the Various Parts of a Fan?

Figure 1: Basic design of a box fan. Source: http://i.ebayimg.com/00/s/NTUyWDY1Nw==/$(KGrHqZ,!gwE63O0iJ)cBO0VVi48Vg~~60_35.JPG

A basic axial fan has relatively few parts. It will contain an electric motor, in most cases, to which the impeller is attached. It may also have a rotating mechanism that turns the fan from side to side as it operates, improving airflow through the space. The fan will generally have a plug in for an outlet. On fans designed for the home, this will usually be a standard plug. On a fan used in a computer, this will usually be a MOLEX connector. In industrial settings and in machinery, the fan may be directly wired into the mains power.

Certain types of fans may have slightly different designs. A centrifugal fan, for instance, will have a housing and a larger mounting structure, usually designed to be bolted into place on machinery or on an appliance.

Fans almost always have a housing. This housing is designed to protect operators and people near the device by making it impossible for them to get their fingers into the fan or to inadvertently put something initiate—tools, for instance—in a fan while working. The fan may also have a housing equipped with a filter, commonly seen on fans that are designed to clean the air of impurities.

 

What Are the Uses for the Continuous Flow of Gas and Air Generated by Industrial Fans?

Fans can be used to move any fluid, depending upon their designs, but they are most often used to move gas and air. This can be done for a range of different purposes.

Cooling is one of the most common uses for fans. Fans pre situated so that they remove hot air from environments, such as in a computer case. They may also be used to introduce cool air into systems, such as in the case of a car’s radiator fan, which provides air flow over the car’s cooling system.

Fans in industrial settings are usually used in similar ways on large machinery. They may be used to either introduce cooler air into a machine or to vent hot air off of a machine. They may move the air through a facility, providing a way to keep heat from building up near the celling and providing fresh air flow into the facility. They may also be used to exhaust air out of the building.

Where gasses are concerned, fans can be used to introduce them or vent them from a space. They are also used in cooling, ranging from air conditioning systems to the coldest freezer units.

Fans are used in extreme circumstances, as well. For instance, in wind tunnel tests, fans may be used to drive airflow over a wing to determine if the design is suitable for flight. Gasses may be introduced into the flow to provide a visual indication of how the air is actually flowing.

Small fans are used on many different types of appliances, ranging from blowers to vacuum cleaners and more.

 

What Is the Difference Between Centrifugal Fans and Axial Fans?

An axial fan pulls air parallel to the rotating shaft at the center of the blades. These are very common and versatile types of fans, seen in a huge range of sizes, powers and applications.

A centrifugal fan blows air at a right angle to the central shaft, using a housing to direct the air or gas with a greater degree of force than an axial fan of the same size.

 

What Is Considered the Fan Design for an Application?

A fan design can be specialized, such as a blower fan intended to be used on a specific piece of machinery. It also may be more general, such as a fan designed to be situated in windows or permanently mounted on the ceiling of a home to provide better airflow.

A fan design may also simply be defined by the size or scale of the fan. The fans used in wind tunnels, for instance, will be very large while the ones used on processors in computers are very small. The fan may be designed in a way that allows it to move a significant amount of air for its size, or positioned in way that accommodates that need.

 

What Types of Fans Exist?

There are many different types of fans availed, ranging from ones that provide airflow only for machinery to ones that are designed specifically for human comfort, such as box fans. Some fans are designed to be low noise. This is popular in computers, where one computer may have many different fans installed in it, creating a great deal of noise if the fans are not designed for specifically quiet operation.

 

Axial Fans

Many of the most common fans are axial fans. They are durable, can be produced in a huge range of sizes and, with powerful motors and large impellers, can move a significant quantity of air. This makes them appropriate for many different uses, from small tabletop fans to fans large enough to provide airflow through an industrial facility or a barn.

Axial fans all use the same impeller arrangement. The impeller is positioned on a shaft and, when started, it pulls air through the fan perpendicular to the direction that ti turns on the shaft. These types of fans can produce a great deal of airflow at low pressures.

Axial fans are inexpensive and provide one of the go-to cooling solutions for myriad needs. The wind-chill that they produce can cool off a room on a hot day. In an enclosed environment, such as in machinery or a computer, they can evacuate hot air from the enclosure or introduce cool air.

 

Blowers

Blowers usually use centrifugal fans to move air. They provide a heavy airflow out of a pathway that increases the power of the airflow. These are commonly seen on hairdryers, industrial dryers, leaf blowers and other equipment that needs to move a great deal of air to function. They come in a range of different sizes, from large devices that are permanent fixtures of machinery to smaller devices that are affixed to portable tools.

They are used in climate control systems, due to their ability to channel a tremendous amount of air down shafts.

 

Desk and Portable Fans

Desk and portable fans are usually axial models that are designed to be compact. They are generally personal fans, designed to blow directly on the user and, thereby, provide a cooling wind-chill, or just to move stuffy air and increase the quality of interior air.

Portable fans are sometimes designed to work off of car accessory ports, allowing them to be mounted on the dashboard and to provide airflow in addition to that provided by the car’s own fans, which are typically centrifugal models that move air through the vents in the dash.

 

Duct Fans

These are commonly cross flow fans, utilized because of their ability to move a great deal of air without taking up a significant amount of space. Duct fans are used specifically to channel air through ductwork, commonly as part of an HVAC system. Axial fans are sometimes used for this purpose, as well, particularly variable pitch fans, which have sophisticated movement capabilities that increase or decrease airflow as needed.

 

Filter Fans

Filter fans are provided with a filtration material that is intended to clean the air of impurities. These may be simple, felt filters that are designed to trap large particles of dust or they may be HEPA filters, which capture material down to a very small size. These fans are commonly used to improve indoor air quality and may be combined with other filtration devices, such as an ionizer, that provides a full solution to interior air quality issues. Some filter fans are installed on HVAC systems to control dust in the system and to improve airflow overall.

 

Plate Fans

Plate fans use the plate portion of their design for mounting purposes. They sometimes have sophisticated features, such as pitch control, that makes them ideal solutions for HVAC systems and other systems that have to move air trough ducts. These are very common types of fans seen in industrial applications.

 

Window and Wall Fans

Window and wall fans are provided with mounting systems that allow them to be positioned advantageously for airflow purposes. Wall fans typically have a mount that allows them to project from the wall, with oscillating designs being particularly popular for these applications.

Window fans are typically designed to project partially out of a window on both sides. Some of them are installed with the screen removed from the window and others can be installed with the screen left in. In the case of the lightest models of these fans, the weight of the top pane of the window resting on the fan housing may be enough to keep it secure. With larger fans, more sophisticated mounting systems may be required. Wall fans may connect to the outside, providing a way to ventilate the building.

 

What Are Enclosure Fan Modules?

Enclosure fan modules come in a housing that allows them to be mounted in specific applications and to direct airflow in a specific way. They are frequently provided with a very compact design and come with various modules, such as screw fixing or other designs.

 

What Is Considered the Flow Control of a Fan?

Fan flow control can be accomplished electrically, by using a variable switch to increase or decrease power to the fan. It can also be controlled by changing the orientation of the fan, such as in the case of axial fans with tilt and pitch controls. These changes in the direction of airflow can also be used to increase or decrease the air flow volume of the fan.

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