Airfoil Lift and Drag Calculator (XFOIL)
Calculate lift and drag using the Airfoil Lift and Drag Calculator powered by XFOIL. Perfect for aerospace engineers and enthusiasts.
How to use
Enter the speed, angle of attack, and air density parameters. Click Calculate or rely on the live updates triggered by input changes. The results reflect a simplified XFOIL-based model that uses an assumed aspect ratio.
Methodology
The lift coefficient approximates \(Cl = 2π α\) with \(α\) in radians. Drag is derived from \(Cd = \frac{Cl^2}{π AR}\) using a fixed aspect ratio of 6. Air density is validated but not directly used in the current simplified engine.
- Angle of attack is converted from degrees to radians to match the small-angle approximation.
- Drag is a quadratic function of \(Cl\) scaled by the aspect ratio and π.
- Density is captured for completeness and future extensions.
Full original guide (expanded)
Data Source and Methodology
The calculator draws from XFOIL-inspired coefficients and references the Airfoil Tools repository.
The Formula Explained
Lift: \(Cl = 2π α\)
Drag: \(Cd = \frac{Cl^2}{π · AR}\) with \(AR = 6\)
Glossary of Variables
- Speed: Airfoil velocity relative to air.
- Angle of Attack: The chord-line angle to oncoming flow.
- Air Density: Mass per unit volume of air (checked for validity).
- Lift Coefficient: Dimensionless coefficient of lift.
- Drag Coefficient: Dimensionless coefficient of drag.
Frequently Asked Questions (FAQ)
What is an airfoil?
An airfoil is a profile designed to produce lift as air flows over it.
How does angle of attack affect lift?
Higher angles generally increase lift until stall occurs.
Why is drag related to the square of lift?
Drag grows with lift squared because induced drag scales with the energy required to produce lift.
Is this calculator accurate for all airfoils?
It is a simplified model; for precise results, run XFOIL or wind tunnel data.