Friends, today in this article we will learn about the types of thermal cycles. I am going to give information about all these in a very good way. So let’s start.
Types of thermal cycles based on the energy sequence used
The thermal cycle can be divided into the following parts based on the use of energy sequences-
Brayton Cycle
This cycle is used in gas turbine plants. Fuel and air are introduced into its internal combustion chamber with high pressure.
In this way, rotation is obtained in the turbine due to the mixture of gas and air. If the high temperature waste gas is reused to generate steam, then this gas turbine is called co-generation system.
The Brayton cycle is used to make the gas turbine heat engine efficient. Through this, air or gas is used as the working fluid in the heat engine.
Piston compressors and piston expanders are used in engines with Brayton cycle. But air conveyor jets are used in modern gas turbine engines. This thermodynamic cycle was first used in 1892. Output power is increased by this.
The isothermal heat cycle is not followed by the Brayton cycle. In comparison, the output efficiency is low in the Carnot cycle due to the isothermal heat cycle.
Applications of Brayton Cycle
Following are the main applications of Brayton cycle-
(i) Brayton cycle is used in jet engines. It is useful for aircraft engines. In jet engines, heat is dissipated in high pressure and temperature turbine with the help of Brayton cycle.
(ii) Brayton cycle is also used in water cycle.
(iii) Brayton cycle is used to reduce losses in heat exchanger.
(iv) Brayton cycle is used for reheating and intercooling.
Rankine Cycle
Rankine cycle is used especially for steam power plants. It is a simple standard boiler system. In this, the steam is completely condensed and sent back to the boiler. The Rankine cycle is shown in Figure 2. In this, steam is produced in the boiler and is incident on the turbine, this steam produces additional pressure on the turbine, due to which mechanical energy starts being produced and this mechanical energy is converted into electrical energy.
When the back pressure of steam is used in any process instead of condensing the entire steam, then this process is called Rankine cogeneration. Rankine cogeneration is shown in Figure 3. In this system, steam enters the turbine chamber at high pressure and expands at low and medium pressure.
The enthalpy difference is used to produce energy. The measurement can then be used in any process at low and medium pressure, followed by the condensation of steam.
Rankine is also known as Vapour Cycle. In this, the working fluid is used in the system by changing the pressure-volume.
With the help of Rankine cycle, nuclear plants can be operated with high efficiency.
Organic Rankine Cycle (ORC)
In internal heat combustion engines, 30% of the fuel energy is converted into mechanical energy, while 70% is spent as losses due to low temperature. Therefore, to reduce the losses, organic Rankine cycle (ORC) is used. It is used in the organic Rankine cycle for organic gases (Pentane, Octane, R-123) as working gases, whose temperature is less than 80°C.
In this, evaporator, expansion device and condenser are used.
In the organic Rakine cycle, the efficiency is assessed on the basis of temperature. When the gases are sent to a high temperature of 400°C in the process, the efficiency of this technique is 20%-24%. If the temperature is close to 200°C, then the efficiency is 8% to 12%. ORC works under phase. Preheater is not required in this. ORC is used in geothermal power plants. Its temperature range is kept from 100°C-400°C. If the temperature is less than 100°C, then its efficiency is low. ORC is used in solar power plants. It increases the efficiency by 15%.
What did you learn today :-
Now you must have known the types of thermal cycles and you must have got the answer to all these questions well.
I hope you liked the information given by me, if you have any question/suggestion in your mind, then you can tell me by commenting below, I will definitely reply to your comment. If you liked this post, then you can also share it with your friends and relatives.