Parasitic Drag Calculator
Estimate parasitic (zero-lift) drag from equivalent flat plate area or skin friction coefficient and wetted area.
Parasitic Drag Coefficient (CD0)
0.01000
Parasitic Drag Coefficient (CD0) vs Skin Friction Coefficient (Cf)
सूत्र
## Parasitic Drag Parasitic drag (also called zero-lift drag or profile drag) is the drag that exists even when the wing is not generating lift. It consists of skin friction drag and form (pressure) drag. ### Formula **CD0 = Cf × Swet / Sref** where Cf is an average skin friction coefficient for the entire aircraft, Swet is the total wetted (exposed to airflow) area, and Sref is the wing reference area. The equivalent flat plate area f = Cf × Swet is a useful metric for comparing aircraft of different sizes.
हल किया गया उदाहरण
An aircraft with Cf=0.003, wetted area 400 m², wing area 120 m², at q=5000 Pa.
- 01CD0 = 0.003 × 400 / 120 = 1.2 / 120 = 0.01
- 02Flat plate area = 0.003 × 400 = 1.2 m²
- 03Drag force = 0.01 × 5000 × 120 = 6000 N
अक्सर पूछे जाने वाले प्रश्न
What is a typical CD0 for transport aircraft?
Clean transport aircraft have CD0 around 0.015-0.025. Streamlined fighters may achieve 0.015 or lower. Light aircraft with fixed landing gear might have CD0 of 0.03-0.05.
What affects skin friction coefficient?
Reynolds number (higher Re means lower Cf for turbulent flow), surface roughness, boundary layer state (laminar vs turbulent), and Mach number all influence Cf. Smooth laminar flow has Cf about 5-10× lower than turbulent.
How does parasitic drag vary with speed?
The coefficient CD0 is roughly constant with speed (at subsonic conditions). But the force D0 = CD0 × q × S grows with V² since dynamic pressure q grows with V². This is why parasitic drag dominates at high speed.
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