High Airflow Vs Static Pressure Fans

The two opposite ends of the blade design spectrum are the af airflow and sp static pressure designed fans.
High airflow vs static pressure fans. Airflow is the amount of air which is the fan is capable of removing at its greatest rpm. In case of static pressure and air flow fans there are a lot of difference. When air flow increases static pressure decreases. For comparison 1 pound per square inch static pressure 1 psi is equal to 27 7 in.
So what exactly is airflow and static pressure. High airflow fans simply push as much air as possible while static pressure fans are specifically designed to tackle installations with heightened impedance and resistance. Water is equal to about 25 pascals pa. The relationship between air flow and static pressure of a fan is shown in the graph above.
The 3 points depict possible scenarios where the fan will perform. Using the fan in the wrong scenario will affect your cooling to a great extent. And when static pressure increases air flow decreases. Af style fans have many thin blades 9 15 typically with a relatively steep angle.
This is a highly efficient design to move airflow volume with the least amount of fan blade noise. The static pressure of 0 1 inches of water in. Following on from my last article where i looked at whether push vs pull vs push pull makes a difference today we are looking at static pressure fans vs airflow fans. The static pressure of one inch of water is the suction needed to draw water up a straw one inch.
As you can see air flow and static pressure have a negative correlation. When it has no restrictions.