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Circulation Lift per Unit Span Calculator
Calculate signed lift per unit span from the Kutta–Joukowski relation for steady two-dimensional circulation flow. Choose input units and calculate one value within the stated conditions.
Inputs
Calculations run in this browser. Scientific notation such as 1.2e-3 is supported. Do not group thousands.
Result
Upward-positive lift per unit span L′
Enter values and select Calculate.
L′ = ρUΓ (clockwise Γ positive, U rightward)
Assumptions
Required: the circulation theorem for steady two-dimensional incompressible inviscid exterior flow. Free stream is rightward, clockwise circulation is positive and upward lift is positive. This circulation sign is opposite to the common counterclockwise-positive convention. Excluded: finite wings, separation, stall and viscous drag.
Displayed values are floating-point approximations. Design safety factors and unprovided error contributions are not calculated.
Formula references and credits
NaNa Lab created the code, descriptions, icons and preview images. Text, figures and code from the linked references have not been reproduced.
Physical constants: NIST / CODATA 2022. The values of μ₀ and ε₀ are measured recommendations, not exact defining constants. Values and precision notes are in the source record.
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