Archive for April, 2009
What is a more efficient car ?
A car that has a low cost, is reliable, is light-weight, has good performance and high mpg.
More Lightweight and Secure Cars
- F=m.a, the smaller the mass the higher the acceleration for a given power.
- Avoid not needed stuff, there is lot…
More Efficient Motors
- Turbo charging: reuse energy from exhaust gas to compress inlet air, less pollution and more power. (http://en.wikipedia.org/wiki/Turbo-compound_engine). Difficult to apply on motor bikes, due to so called lag but should work. Water intercoolers help to limit turbo lag due to their size.
- Multi-Stage turbo charging for diesel: small turbo followed by a bigger one. Given a small displacement motor it is possible to achieve very high power output, 200 BHP/liter is achievable. Water intercoolers are very helpful in such case to limit lag.
- Compounding: takes kinetic energy from exhaust gas using a turbine and gears reduction to crank-shaft (http://en.wikipedia.org/wiki/Turbo-compound_engine), about 20 to 25% more torque (and thus power). Can be use on motor bikes, there is no lag as for a turbo.
- Kinetic Energy Recovery: takes energy when braking to spin quickly a disc, helps to have some amounts of torque for acceleration. Better power/weight ratio than batteries, that why it is used in Formula 1. (http://en.wikipedia.org/wiki/Regenerative_braking). I think it is also very useful on motor bikes with a tiny hydraulic motor on the front wheel.
- Variable Compression Ratio: more efficient motor on low and mid range. (http://en.wikipedia.org/wiki/Variable_compression_ratio). For gasoline engine, water injection can be used to save precious gasoline while achieving more power.
- Constant Variable Transmission: can replace a whole gearbox and is lighter (http://en.wikipedia.org/wiki/Continuously_variable_transmission)
- Electric water pump: low and mid-range needed coolant flow is bigger than high rpm. Most mechanical water pump are over designed. This is very useful for trucks and heavy duty motors.
- Alternator/Starter Motor: limits weight and can be used to put additional power on low to mid range revs.
- Higher voltage: cost saving for copper and save weight.(Power=Voltage.Intensity)
- Compounding, Kinetic Energy Recovery: can be used to generates electricity, to refill batteries.
- Thermal Energy from Motor: takes thermal energy and generates electricity, helps to refill batteries.
- Supercapacitor: a reserve of electric power to smooth power demand on batteries. It allows faster acceleration. (http://en.wikipedia.org/wiki/Supercapacitor)