Mechanical Engineering

DIFFERENCE BETWEEN CLOSED CYCLE GAS TURBINE AND OPEN TYPE GAS TURBINE

The difference between closed cycle gas turbine and open cycle gas turbine can be done on the basis of source of heating, types of working fluid, circulation of air, wearing capacity of turbine blades, installation, maintenance cost and much more. The basic difference between them is the circulation of working fluid. In the closed cycle gas turbine the same working fluid is circulated again and again within the turbine but in the open cycle gas turbine the working fluid i.e. air is replaced again and again while flowing through the gas turbine.

Comparison of closed cycle gas turbine and open cycle gas turbine in tabular form:

S.no	Closed Cycle Gas Turbine	Open Cycle Gas Turbine
1.	In this first the air is compressed in the compressor and then heated in a heating chamber. As the air is heated by an external source, so the amount of the gas remains same.	Here the compressed air is heated in the combustion chamber. So the products of combustion gets mixed with the heated air and hence the amount of gas does not remain same.
2.	In closed cycle gas turbine, the gas that comes out from the gas turbine passes into the cooling chamber.	In open cycle, the gases coming out from the gas turbine is exhausted in the atmosphere.
3.	The working fluid is circulated continuously.	The working fluid is replaced continuously.
4.	Any other fluid that possesses better thermodynamic properties like helium can be used.	Here only air can be used as the working fluid.
5.	No earlier wear of the turbine blades, because the enclosed gas does not gets contaminated while flowing through the heating chamber,	Earlier wear of turbine blades,  as the air form the atmosphere enters the combustion chamber it gets contaminated.
6.	It is best suited for the stationary installation and marine uses because the air from the turbine is cooled by the circulating water.	It is best suited for the moving vehicle because the air from the turbine is discharged into the atmosphere.
7.	The maintenance cost of this type of turbine is high.	Its maintenance cost is low.
8.	More mass of installation per kW.	Less mass of installation per kW.