Fans that create a pressure difference are called radial fans. The generated airflow functions in the direction of centrifugal force. A centrifugal fan is a mechanical device used to move air or other gases. These fans feature a rotating wheel, much like a pump, enclosed within a spiral-shaped housing. Air or gas enters parallel to the axis at the center, is pressurized, and is then expelled tangentially through ducts to the outlet.

Due to the high pressure they generate, centrifugal fans are ideal for high-pressure applications such as drying and air conditioning systems. All moving parts are enclosed, which, combined with their particle-reducing properties, makes them suitable for use in air pollution and filtration systems.

Applications of Radial Fans

When axial fans fall short in pressure and flow rate
Duct applications
Solid-fuel boiler systems
Exhausting hot air in high-temperature environments
General and industrial buildings
Warehouses, depots, and storage areas
Garages and public buildings
Agricultural buildings
Commercial greenhouses
Large workshops
Paint booths
Factories
Dusty and vapor-filled environments
Cooling industrial machinery (e.g., welding machines, transformers, compressors)

Radial Fan Housing and Impellers

The radial housing is made from high-quality cold-drawn steel (DKP sheet).
Coated with environmentally friendly, electrostatic epoxy powder paint for high corrosion resistance.
Forward-curved galvanized radial impellers are dynamically tested to ISO 1940 standards.
Manufactured to EN 60335-2-80 standards.
The inlet nozzle design ensures high pressure and flow rates.
Air intakes are protected by mesh guards against foreign object entry.
Robust and precise body structure with special seam joints.
Low noise levels.
Left and right mounting options for desired installation orientation.

Radial Fan Motors

Precision manufacturing on high-tech CNC machines without manual intervention.
High heat conductivity aluminum-finned motor housing.
Balanced rotors conforming to ISO 1940 standards ensure long bearing life.
Insulation class F provides a broad operating range (-40°C to +70°C).
Single-phase fans (230 V / 50 Hz).
Three-phase fans (400 V / 50 Hz).
Certified components conforming to relevant standards.
IP 54 protection class (optional IP 55 available).
Option for inverter control in three-phase fans.

Key Factors in Fan Selection

When selecting a fan, consider these four parameters:

Required air volume (flow rate)
Pressure losses
Acceptable noise level
Type of electrical power connection

The required air volume for a space depends on its intended use, the number of people, and the activities within it. The table below lists air exchange rates for different environments:

Environment	Air Exchange Rate (per hour)
Auditoriums	6–8
Paint booths	25–50
Vault rooms	3–6
Cinemas and theaters	5–8
Commercial kitchens	15–30
Foundries	8–15
Gyms	4–6
Laundries	10–20
Indoor pools	3–4
Restaurants	8–12
Conference rooms	6–8
Waiting rooms	10–15
Machine rooms	10–40
Shops	4–8
Dry cleaners	5–15
General workshops	4–8
Hospitals	8–12
Laboratories	8–15

Calculating Air Volume

The air volume required is calculated as follows:
$Q \, [ \text{m³/h} ] = \text{Air exchange rate (per hour)} \times \text{Room volume (m³)}$
OR
$Q \, [ \text{m³/h} ] = \text{Number of people} \times \text{Air required per person (m³)}$

Example Calculation

In an office where 5 people work:

Ceiling height = 2.6 m
Floor area = 50 m²
Volume = $2.6 \times 50 = 130 \, \text{m³}$
Air exchange rate for offices = 4–8 (use 5 for this example)

Air needed for the room:
$130 \times 5 = 650 \, \text{m³/h}$

Air needed for people (normal activity):
$5 \times 29 = 145 \, \text{m³/h}$

Total air requirement:
$650 + 145 = 795 \, \text{m³/h}$

Fan Installation

After calculating the airflow, determine the installation location: ceiling, wall, chimney, or duct. Another consideration is the electrical voltage supply.

For our office example:

Fans are typically mounted on walls or windows.
Use a single-phase fan for home/office applications.
Use a three-phase (380 V) fan for industrial applications.

Dündar CT 18.4 Radial Snail Fan Aspirator (Three Phase) 1100 m³ 1445 RPM