Cycling Power and Speed Calculator: Difference between revisions
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https://www.gribble.org/cycling/power_v_speed.html | https://www.gribble.org/cycling/power_v_speed.html | ||
=Example= | |||
==High Speed== | |||
*Drag coefficient of 0.1 from an airfoil type body | |||
*Vehicle 300 lb, rider 165 lb | |||
*150W of leg power | |||
*Frontal area of 8 square feet | |||
*Crr = 0.1 for mountain bike tires | |||
*1000W gives 50 mph -realistic but best case scenario | |||
*Adding more length at back gets more power, no more drag | |||
*Thus, a practical car can be made, esp if it has batteries or small generator (1kW) for extra power. | |||
==Low Speed== | |||
*Same parameters as above, 500W of power - gets you 35 mph | |||
=Notes= | =Notes= | ||
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*Best cars are at cd=0.22 - [https://www.motoringresearch.com/car-news-list/most-aerodynamic-new-cars-2018/], and VW XL1 cd=0.19 [http://motorburn.com/2014/01/12-of-the-most-aerodynamic-cars-in-production-right-now/]. Impractical cars can do better. | *Best cars are at cd=0.22 - [https://www.motoringresearch.com/car-news-list/most-aerodynamic-new-cars-2018/], and VW XL1 cd=0.19 [http://motorburn.com/2014/01/12-of-the-most-aerodynamic-cars-in-production-right-now/]. Impractical cars can do better. | ||
*Aptera - lowest cd=0.15 in history for a production car[https://en.wikipedia.org/wiki/Aptera_2_Series], which is 850 mpg equivalent. | *Aptera - lowest cd=0.15 in history for a production car[https://en.wikipedia.org/wiki/Aptera_2_Series], which is 850 mpg equivalent. | ||
*Stingray/Stealth bomber/airfoil mix type bodies can be around 0.1 | *Stingray/Stealth bomber/airfoil mix type bodies can be around 0.1 | ||
Revision as of 17:52, 29 January 2019
Solar vehicle version, 8'x16' body - so 1000W of solar panels.
This would go at 25 mph with a 300 lb vehicle weight, 165 lb rider weight, with 5 square foot frontal area with 500W of power according to this calculator -
https://www.gribble.org/cycling/power_v_speed.html
Example
High Speed
- Drag coefficient of 0.1 from an airfoil type body
- Vehicle 300 lb, rider 165 lb
- 150W of leg power
- Frontal area of 8 square feet
- Crr = 0.1 for mountain bike tires
- 1000W gives 50 mph -realistic but best case scenario
- Adding more length at back gets more power, no more drag
- Thus, a practical car can be made, esp if it has batteries or small generator (1kW) for extra power.
Low Speed
- Same parameters as above, 500W of power - gets you 35 mph
Notes
- Biggest gain is obtained from reducing coefficient of drag due to wind. Air foil (wing) has the lowest drag - less than 0.1
- Best cars are at cd=0.22 - [1], and VW XL1 cd=0.19 [2]. Impractical cars can do better.
- Aptera - lowest cd=0.15 in history for a production car[3], which is 850 mpg equivalent.
- Stingray/Stealth bomber/airfoil mix type bodies can be around 0.1