寄生阻力计算器 — 公式
## 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.
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.
计算示例
An aircraft with Cf=0.003, wetted area 400 m², wing area 120 m², at q=5000 Pa.
- CD0 = 0.003 × 400 / 120 = 1.2 / 120 = 0.01
- Flat plate area = 0.003 × 400 = 1.2 m²
- Drag force = 0.01 × 5000 × 120 = 6000 N