Cooling Fan: Relationship Between Air Flow, Static Pressure, and Equipment Cooling Efficiency
Consideration of Pressure Loss
The optimal cooling fans for equipment and machines depend on the difference in mounting density (difficulty of air passage) inside the equipment.
-
High mounting density
= High pressure loss
= Internal structures and equipment are laid out to resist air flow, making it difficult for air to pass through -
Low mounting density
= Low pressure loss
= Pressure loss is low = Internal structures and equipment do not resist air flow, allowing air to pass through easily
When mounting density is high, use a cooling fan with high static pressure, and when the mounting density is low, use a cooling fan with high air flow for efficient cooling.
Installation Method of Cooling Fans and Differences in Air Flow - Static Pressure Characteristics
| Installation Method for 2 Parallel Fans | Installation Method for 2 Series Fans | The Method of Installing Fans on the Intake Side and Exhaust Side (Push-Pull) | |
|---|---|---|---|
| Notion image |
|
|
|
| Suitable Situations | It is suitable for applications where pressure loss in the equipment is low, and the air flow needs to be increased. |
It is suitable for the following cases.
|
Air flow from the intake side to the exhaust outlet side is possible, thus enabling effective cooling.
|
| Air Flow - Static Pressure Characteristics* |
|
|
|
- *In the case of MU1238A-11B
Change in Air Flow - Static Pressure Characteristics Due to Installation of Accessories
When incorporating cooling fans into equipment, accessories such as finger guards and filters can be installed to improve the overall safety and reliability of the equipment. However, since accessories create blowing resistance, and affect the characteristics and noise aspects of the cooling fans, it is necessary to take this into consideration when selecting cooling fans and accessories.
The figure on the right shows the pressure loss measured in accessories for a cooling fan with a 119 mm frame size. The filter has the highest loss, while the finger guard has almost no loss.
Using the MU1225S-11 as an example, the figure below shows how the characteristics change when accessories are installed.
As can be seen from the figure, the larger the pressure loss in the accessory to be installed, the lower the air flow - static pressure characteristics.