What is a Sterling Engine

Sterling engine is a very simple heat engine, which is operated by expansion and contraction of air and it changes heat energy into mechanical work. The working of this engine is much uncomplicated; it works on cooling the gas, compressing cold gas heating gas and expanding hot gas. This cycle continues over and over again and the engine converts heat energy. Its efficiency depends a lot upon the difference of cold and hot gasses temperature. The greater the difference in temperature the more efficient the engine is. Thus, it can be said that the temperature difference of hot and cool gasses is directly proportional to the efficiency of the engine, which means increasing the difference will increase efficiency and visa versa.

Components Used in Sterling Engine

There are not many components, which are used in sterling engine, some of the components which are traditionally used in making sterling engine are,

  • Displacer
  • Heat Sink
  • Cooler
  • Regenerator
  • Heater
  • Heat source
  • Thermal Insulation

There are lots of variations, which are used in making sterling engine. The designs of these engines vary a lot with respect to the region in which they are made. But they all use the same concept of making the engine work.

Alpha Sterling Engine

In this type of engine there are 2 separate power pistons, which are used to compress and expand gasses. And regenerator is connected with both the cylinders with a pipe. This is the most common type of sterling engine which one can find, but it also comes with some technical issues, which are related to high temperature and piston issues. This type of engine has a very high power to volume ratio.

Beta and Gamma Sterling Engine

Beta engine is another variation of sterling engine, which uses only one power piston in the same cylinders as that of the displacer piston. The advantage of using beta sterling engine is that it eliminates the issue of hot moving seal and other technical problems. Also it uses lesser space than the traditional alpha engine. There are also many other variations of sterling engine other than alpha and beta engine are Franchot engine, Free piston, two cylinder sterling engine with Ross yoke, Fluidyne engine, rotary sterling, rotary combustion engine. Sterling engines are highly effective and they are in existence since 1816, and since then lots of engine have been designed based on it.

Sterling engine can be used to do lots of different types of mechanical work. And hence it is used in many industries, which is why sterling engine became so popular. Size of these engines was an issue in early years but now they are available in compact shapes and sizes.