Fan Laws Calculator
Fan affinity laws for speed changes
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New Conditions
New Fan Performance
New CFM
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New RPM
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New Static Pressure
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New BHP
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Speed Ratio
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Fan Affinity Laws
Law 1: Flow
CFM₂/CFM₁ = RPM₂/RPM₁
Law 2: Pressure
SP₂/SP₁ = (RPM₂/RPM₁)²
Law 3: Power
BHP₂/BHP₁ = (RPM₂/RPM₁)³