免费骑行功率计算器
根据速度、坡度和体重估算骑行功率输出。
Estimated Power
123 W
Estimated Power vs Speed
公式
## How Cycling Power Is Estimated Power required to cycle comes from three main sources: aerodynamic drag, rolling resistance, and gravity. ### Formula **Total Power = P_aero + P_rolling + P_gravity** - **P_aero = 0.5 x air density x CdA x v^3** (CdA assumed 0.32 x 0.88) - **P_rolling = Crr x mass x g x v** (Crr assumed 0.005) - **P_gravity = mass x g x gradient x v** Where v is speed in m/s, g is 9.81 m/s^2. ### Key Insight Aerodynamic drag increases with the cube of speed, so doubling your speed requires roughly 8 times the power to overcome air resistance.
计算示例
Riding at 18 mph on flat road, 185 lbs total rider+bike weight.
- 01Speed = 18 * 0.44704 = 8.05 m/s
- 02Mass = 185 * 0.4536 = 83.9 kg
- 03P_aero = 0.5 * 1.225 * 0.2816 * 8.05^3 = 90.0 W
- 04P_rolling = 0.005 * 83.9 * 9.81 * 8.05 = 33.1 W
- 05P_gravity = 0 (flat road)
- 06Total = 90 + 33 + 0 = 123 W
- 07W/kg = 123 / 83.9 = 1.47 W/kg
常见问题
What is a good watts per kg for cycling?
Recreational: 1.5-2.5 W/kg, competitive amateur: 3-4 W/kg, professional: 5-7 W/kg at threshold.
Why does power increase so much at higher speeds?
Aerodynamic drag grows with the cube of speed. Going from 15 to 20 mph requires roughly twice the power, even on flat ground.
How accurate is this estimate?
This provides a reasonable estimate assuming standard road conditions. Real power depends on wind, drafting, road surface, tire pressure, and rider position.
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