Some different engines used in cars.

Stirling engine outputs power through the cycle of cooling, compression, heat absorption and expansion of working medium (hydrogen or helium) in cylinder, so it is also called heat engine. An important application field of Stirling engine is as an energy conversion device for solar thermal power generation.

2. Rotary engine

The rotary engine was invented by a German named Figas Wankel. On the basis of summarizing the previous research results, he solved some key technical problems and successfully developed the first rotary engine. Rotary engine uses the rotary motion of triangular rotor to control compression and emission, which is very different from the traditional linear motion of reciprocating piston engine.

3. Star engine

Star engine is a reciprocating internal combustion engine with cylinders arranged around the crankshaft. Its piston is connected with the crankshaft through the main connecting rod. The connecting rod connected by the uppermost piston is the main connecting rod, and the connecting rods of other pistons are called articulated connecting rods, which are connected in the main connecting rod through pin holes.

4. Air cooled engine

The applicable working temperature span is larger, and the range of water-cooled engine is smaller (50~ 180℃ for air cooling and 85 ~ 95℃ for water cooling); The invention has the advantages of simple structure, light weight, low manufacturing cost, high power utilization rate, no water leakage, icing, scaling and other faults, convenient use and maintenance, good environmental adaptability and short warm-up time after starting.