Power machinery is a mechanical device that converts energy in nature into mechanical energy. Power machinery has profoundly affected the development of human productivity. However, the noise of power machinery, especially the emissions of heat engines, has caused more and more serious harm to human beings.
As early as the first century AD, Hero of Alexandria had discussed the machinery driven by water, wind and hot air. Later, people began to use wind, windmills, waterwheels and water mills that use wind and water in their living and production activities.
The advent of steam engines at the end of the 18th century opened up the use of chemical energy, greatly increasing labor productivity and leading to the industrial revolution. At the end of the 19th century, the invention and application of internal combustion engines provided power for automobiles, locomotives, and ships, and led to the invention of aircraft. The appearance of the human transportation industry has undergone tremendous changes, and the tremendous development of the machinery manufacturing industry has been promoted.
From the end of the 19th century to the beginning of the 20th century, with the invention of steam turbines, gas turbines, jet engines and rocket engines, the speed of vehicles has been greatly improved, people's exchanges have become more convenient, the field of human activities has become more open, and the space industry has been opened up, thus further driving And promoted the development of other scientific and industrial sectors.