CFM is short for cubic feet per minute (cu ft/min). It is a measurement of the velocity at which air flows into or out of a space. The CFM measurement often is used in reference to a computer’s cooling system, and more typically in reference to an air-cooling system that is supporting overclocking. It is a measurement also used in the data center.
CFM in the Data Center
In the data center, heat is often removed from server equipment by increasing the airflow, expressed in CFM — an increase in CFM equates to an increase in heat removal. There must be enough CFM that the equipment does not overheat. A common way to achieve optimal CFM is through the use of larger fans or better quality fans with improved blades, so improved CFM is typically achieved at a higher capital costs, the ongoing cost of electricity and could accompany a noticeable increase to noise levels.
CFM Beyond Computing
CFM is not limited to computing-related measurements. In fact, it is the standard for air flow measurement and is used in many systems including bathroom or kitchen ventilation, heating systems, industrial fans, greenhouses and many other places where airflow is a consideration.