* Internal Combustion:
* Fuel is burned *inside* the engine cylinders.
* The burning fuel creates expanding gases that push pistons, generating power.
* This direct conversion of fuel energy into mechanical work is very efficient.
* External Combustion:
* Fuel is burned *outside* the engine, typically in a separate boiler.
* Heat from the combustion is used to create steam or heat a working fluid.
* The working fluid then drives a separate mechanism, like a turbine or piston, to generate power.
Why cars use internal combustion:
* Higher Power-to-Weight Ratio: Internal combustion engines are relatively lightweight and compact for the power they generate. This is crucial for vehicles.
* Faster Response Time: Internal combustion engines can react quickly to throttle changes, providing immediate power for acceleration.
* Historical Development: Internal combustion engines were developed earlier and were more efficient than external combustion engines for automotive applications.
While internal combustion engines have dominated for decades, there are advantages to external combustion in certain applications, such as:
* Lower Emissions: External combustion can be more efficient at capturing and utilizing the heat produced, leading to lower emissions.
* Fuel Flexibility: External combustion engines can run on a wider variety of fuels.
In summary, the internal combustion engine is well-suited for car applications due to its high power-to-weight ratio, rapid response, and historical development. However, external combustion engines offer advantages in specific situations and are being explored for future applications.
