The airflow of the cooling fan
Category:
News Center
Industry Trends
Release time:
2021-11-08
The airflow and static pressure of a cooling fan are important indicators for evaluating the performance of a heat sink. Airflow is typically measured in cubic feet per minute (CFM). Here are some common conversions for airflow units: 1 CFM = 28.316846592 L/MIN = 0.028 CMM. The unit for static pressure is generally millimeters of water column (mmH2O).
The calculation of the fan’s airflow and static pressure parameters for the radiator is performed using a specialized piece of equipment—the wind tunnel. The heat sink is mounted on the wind tunnel, and air is blown through the heat sink, completely entering the cylindrical chamber in the middle of the wind tunnel. Inside this chamber are sensors that transmit data to a database for processing, thereby generating the airflow and static pressure values.
Since wind tunnel equipment is not inexpensive, some manufacturers opt to purchase handheld anemometers to measure wind speed. However, these anemometers can only provide a simple comparative measurement of wind pressure values.
Generally speaking, the greater the airflow, the better the heat dissipation performance. Additionally, the structure of the system being cooled plays a significant role—this includes the air intake, exhaust vents, and airflow channels. Another important parameter closely related to air pressure is the airflow volume of the cooling fan: the higher the airflow volume and the greater the air pressure exerted by the fan, the faster the heat dissipation will be. Therefore, when evaluating cooling performance, two key parameters are crucial: airflow volume and air pressure.
The commonly used cooling fans are typically frame- or square-shaped, though some special types—such as tripod-mounted or single-letter-mounted fans—also exist. There are both framed and frameless heat sinks. Which type of heat sink produces a greater airflow?
Let’s first take a look at the airflow of cooling fans. Simply put, airflow refers to the volume of air that a cooling fan delivers when it’s operating. We’ll abbreviate airflow as “airflow” or “airflow data.” The airflow data is obtained through wind-tunnel testing. The testing method involves directing the airflow generated by the heat sink entirely and without any loss into the wind tunnel. Inside the wind tunnel, there’s a sensor that transmits the data to a database, enabling the calculation and output of airflow measurements.
There’s another point to note: the magnitude of the wind and its related factors primarily depend on the shape of the fan blades, followed by the shape of the outer frame.
So, when comparing square heat sinks and frameless heat sinks, the key factor to consider is the airflow volume. First, we need to determine which type of heat sink generates a greater airflow volume. Second, we should evaluate the frame’s ability to collect and direct airflow. However, since frameless cooling fans disperse their airflow in all directions, they can’t efficiently channel all the air into the air duct. Therefore, it’s impossible to directly compare the airflow volumes of these two types of fans on a standalone basis—unless we combine the frameless fan with a heat sink, allowing the airflow to be directed from a single point, and then measure the combined airflow volume.
Related News
On these busy days, I’m grateful to have you all fighting side by side! At this company dinner, everyone can put aside their daily hustle and enjoy some wonderful moments together. Let’s raise our glasses and chat freely—may delicious food and laughter accompany us as we strengthen our team spirit and build an even warmer sense of unity!
2025-08-27
The weekend team-building event by the seaside came to a perfect close! With sunny beaches and endless laughter, the team collaborated seamlessly in fun-filled games, relaxing their minds and bodies amid the soothing sound of ocean waves. Filled with renewed energy, we’re ready to join hands and tackle new challenges together!
2025-08-25
The newly installed display cabinets at the Huizhou company are gradually being filled up...
2025-08-21
Jiangshan Lai Electronics wishes you a happy Mid-Autumn Festival 2022!
On a day of blooming flowers and a full moon, When families are reunited in joy, May our land send you warm wishes for a happy Mid-Autumn Festival!
2022-09-10
Jiangshan wishes you a healthy and happy Dragon Boat Festival 2022!
The fragrant aroma of zong leaves fills the air on May 5th— May our heartfelt wishes bring you peace and well-being this Dragon Boat Festival! May our land send its best wishes for your health and happiness this Dragon Boat Festival 2022!
2022-06-03
May the land and rivers bring you joy as we celebrate Labor Day!
Salute to the workers! May our country and its people bring joy and happiness to all our customers and employees on this special occasion!
2022-05-01
Advantages and Applications of Oil-Bearing DC Fans
The pivot joint is fixed at the position of the motor stator base, ensuring an appropriate gap between the rotor and the stator. Of course, there must also be a clearance between the shaft core and the bearings to prevent the shaft core from becoming locked and thus unable to function. The stator structure of the motor—hereafter referred to as the "stator"—is designed in such a way that, once power is supplied, an induced magnetic field will be generated between the rotor and the stator. The control circuit then drives the electric fan motor into operation. Therefore, in the conventional fan motor design, as long as the fan rotor, the motor stator, and the drive circuit work together via the pivot joint between the shaft core and the bearings and through magnetic field induction, the motor can operate effectively.
2022-04-18
FRIENDLY LINK：
3rd Floor, 59 Yanshan Avenue, Yanchuan Community, Yanluo Street, Bao 'an District, Shenzhen
Which DC fan wholesale manufacturer is better, the recommended DC fan supplier rankings, the price of brushless DC fans, and what are the