What is Air Pressure ?

The efficiency testing metrics of fan are normally classified into air pressure and air flow. The air pressure can be explained as the difference in pressure resulted from the fan while the testing air flow is zero.

 

What is air flow-air pressure curve?

Air flow-air pressure curve is the most important benchmark data while evaluating the efficiency of the fan. It is detected through a nozzle testing device, but the data of air flow can not represent the fan’s efficiency completely. The air flow value represent the maximum air flow which is detected in the free air space, but there will exist some resistance in normal system (hard drive, graphic card, heat sink, etc), therefore it can not reach the marked maximum air flow. To know how much air flow will remain, the cross point, which indicates the real air flow during system operation, needs to be marked between system resistant curve and air flow-air pressure curve.
 
 
Why a large air pressure fan is needed?
When system resistance increases, a fan with air pressure enough to counteract high air resistance will not lose too much air flow. The following graph shows the comparison between FM122 and other standard fan at 2400 rpm. From the graph, it can be seen that within the high pressure condition, FM122 performs better than other standard fans. Generally speaking, the air resistance of the fan on the cooler is larger than case. FM122 is a cooling fan with the superior air pressure performance, therefore, we recommend using FM122 with cooler.