Radiator Fan CFM vs Static Pressure Calculator
Case fans rated for 70 CFM lose 40% to 65% of their airflow when pushing through dense watercooling radiators. Calculate true delivered CFM, heat dissipation (Watts), and push-pull benefits.
โ๏ธ Fan & Radiator Specs
This fan possesses sufficient static pressure (2.34 mmH2O) to overcome the 20 FPI radiator core without stalling. You retain approximately 58% of free-air CFM, dissipating up to 420W of CPU/GPU heat load silently.
๐ Why High CFM Doesn't Equal Great Radiator Cooling
Airflow Fans vs Static Pressure Fans
Standard case fans have wide gaps between fan blades and shallow pitch. In free air they move huge volumes (70+ CFM), but against a radiator, backpressure forces air to slip backwards between the blades. Static Pressure (P-Q optimized) fans use steep, tightly overlapping blades with minimal tip clearance (under 0.5mm) to force air through dense copper fins.
When Does Push-Pull Actually Matter?
On slim 27mm or 30mm radiators with standard 16-20 FPI, push-pull yields only a minor 10-15% airflow gain at the cost of double the fan noise and space. However, on thick 45mm or 60mm radiators, static resistance climbs exponentially; push-pull doubles available static pressure, unlocking up to 35% more heat dissipation.