Temperature versus flow rate [edit]
The equation for required airflow through a chassis is
whereCFM = Cubic Feet per Minute
Q = Heat Transferred (kW)
Cp = Specific Heat of Air
r = Density
DT = Change in Temperature
A simple conservative rule of thumb for cooling flow requirements, discounting such effects as heat loss through the chassis walls and laminar versus turbulent flow, and accounting for the constants for Specific Heat and Density at sea level is: (Please Note It must be between sea level)
For example, a typical chassis with 500 watts of load, 130 °F max. internal temperature in a 100 °F °ree; environment (a 30 deg temperature rise):
This would be actual flow through the chassis and not the free air rating of the fan.
The equation for required airflow through a chassis is
whereCFM = Cubic Feet per Minute
Q = Heat Transferred (kW)
Cp = Specific Heat of Air
r = Density
DT = Change in Temperature
A simple conservative rule of thumb for cooling flow requirements, discounting such effects as heat loss through the chassis walls and laminar versus turbulent flow, and accounting for the constants for Specific Heat and Density at sea level is: (Please Note It must be between sea level)
For example, a typical chassis with 500 watts of load, 130 °F max. internal temperature in a 100 °F °ree; environment (a 30 deg temperature rise):
This would be actual flow through the chassis and not the free air rating of the fan.
