Gas turbine cycle
Gas turbine cycle is a thermodynamic cycle that converts the energy in fuel to useful work and heat. This cycle is widely used in power generation, aerospace propulsion and marine propulsion. It is a type of internal combustion engine in which air is compressed, heated, and then allowed to expand to perform work.
The gas turbine cycle is divided into two types: open cycle and closed cycle. In open cycle, only hot gases are expanded to perform work. These open cycle engines are used in the aerospace industry, where the inability of the engine to exchange heat with the environment limits its efficiency. In closed cycle, hot gases are expanded and cooled to perform work, and the exhaust gases are compressed and reheated before being discharged. These closed cycle engines are used in the power generation and marine propulsion industries, where the availability of heat exchange devices increases efficiency.
The basic components of a gas turbine cycle are the compressor, combustion chamber, turbine, and the exhaust pipe. The compressor is used to increase the pressure, temperature and volume of air entering the combustion chamber. The combustion chamber is where the fuel is burned in the presence of pressurized and heated air. The turbine is used to drive the compressor, generating the power output. And the exhaust pipe is used to release the exhaust gases to the environment.
When fuel and air are added to the combustion chamber, they undergo rapid combustion due to the high temperature and pressure. This causes the nitrogen and oxygen molecules to mix with the fuel particles, increasing their thermal and chemical energy. The resulting hot gas expands and pushes the turbine blades which rotate the generator, producing electricity. Some of this energy is used to drive the compressor which compresses and heats the air for subsequent rounds of fuel combustion. The remaining energy is produced as useful work (the electricity generated) or released to the environment as heat.
At the end of the cycle, the exhaust gases are released to the environment. During this process, the gases also lose energy in the form of heat due to friction. This heat energy is released to the environment, thus lowering the efficiency of the process.
The gas turbine cycle is one of the most efficient and versatile combustion processes available, and it is widely used in numerous applications. It is highly reliable and the most efficient form of energy conversion, making it an important part of modern technology.