A free-piston engine is a linear crank less internal combustion engine. Combination of a reciprocating engine and a rotary turbine. It consists of a gasifier and a turbine. Compressor piston is directly attached to a diesel piston. The piston is free because its motion is not controlled by the position of a rotating crankshaft Hence, It is called a free-piston engine. Important features of the free-piston engine are potential reductions in frictional losses. Let us have a deep insight into the pros and cons of the free-piston engine in this article.
Advantages of the free-piston engine :
- Mechanical simplicity.
- Flexibility and reliability.
- Power to weight ratio.
- Multi-fuel capability.
- Low turbine operating temperature.
- Less vibration and noise.
- Less maintenance.
- Easy to start the piston.
- Highly suitable for waste heat recovery.
- Give a high degree of manoeuvrability.
- Less manufacturing cost.
- Low NOx emissions.
- It offers the HCCI combustion process.
- Internally balanced.
- Modularity.
Disadvantages of free-piston engine :
- Poor fuel economy.
- Stability of fuel supply.
- Poor part-load efficiency.
- High combustion rate.
- Reduction gearing is required.