1. PES COLLEGE OF ENGINEERING , MANDYA
MECHANICAL ENGINEERING
PRESENTATION
UNIT : ENERGY CONVERSION SYSTEMS
TOPIC : CLOSED GAS TURBINE
Presented by Guided by
Monisha G T Prof. Siddesh Kumar N M
USN:4PS21CS056
2. WHAT IS CLOSED GAS TURBINE ?
A Closed-cycle gas turbines can be defined as gas turbines that
uses a gas for the working fluid as a part of closed thermodynamic
system.
In this type of turbine, the air is continuously circulated within the
gas turbine with the help of a compressor, heat chamber, gas
turbine, and cooling chamber. It performs a thermodynamic cycle,
which means that the fluid is circulated and used continuously
without leaving the system.
3. A closed-cycle gas turbine
method is adopted to overcome the
disadvantages of an open cycle gas
turbine method.
The corrosion and erosion of
turbine blades is the main
drawback in an open cycle. This
drawback can be overcome by using
superior quality of working medium
(air or helium, argon, hydrogen or
neon) where it doesn’t mix with the
fuel in the combustion chamber.
The other advantage of using a
closed cycle method is, the rejection
of heat of exhaust gases takes place
in a re-cooler or re-heaters or heat
exchangers.
W H Y C L O S E D G A S T U R B I N E ?
4. The closed cycle gas turbine works on the basis of
the Brayton cycle or Joule’s cycle.
It consists of a Compressor, Heater ,Turbine and
Cooler.
Gas is compressed isentropically in this type of
gas turbine by a compressor, which then flows
into a heating chamber.
An external heat source is used to heat the
compressed air before it is passed over the turbine
blades.
As the gas streams over the turbine blades, it
expands to low pressure driving the turbine shaft
producing the mechanical energy of rotation.
The gas exhaust from turbine enters the cooling
chamber, where it is cooled down. Through the
circulation of water at constant pressure, the gas is
cooled to its initial temperature. Continuing the
process, the gas is again passed into the
compressor and the cycle repeats.
Working Principle of Closed
Cycle Gas Turbine
5. Excellent thermal efficiency at all temperatures and
pressure ratios
Use of any working fluid with low caloric value, such as
helium
Corrosive-free
No need to clean the inside
The small size of the gas turbine
The higher the pressure, the better the heat transfer
coefficient in the exchanger
Less fluid friction loss
Advantages of Closed Cycle Gas
Turbine
Closed cycle gas turbines have the following advantages:
6. The entire system is working under high pressure
with a working fluid (medium), which increases
the cost.
The combustion chamber, when used in the open
cycle, is not
This type of gas turbine is not suitable for
aeronautical engines because it uses water for
cooling.
A complex system is needed to be able to
withstand high pressures.
Disadvantages of closed-cycle gas
turbines:
enough to heat the air, which here the closed
cycle needs a very large air heater.
7. APPLICATIONS
Used in the generation of electric power
Used in many industrial applications
Used in marine propulsion, locomotive
propulsion, automotive propulsion
Used in aviation to provide power to the jet
Propulsion
T H E C L O S E D - C Y C L E G A S T U R B I N E
A P P L I C A T I O N S I N C L U D E T H E
F O L L O W I N G .
8. Air
Helium, along with other noble gases
Nitrogen
S-CO2
Solar
Nuclear
Fossil
Biomass
Types of Closed Cycle Gas Turbine
Initially, closed cycles are classified based on working fluid and heat source.
Working Fluid
Gases that can be used as the working fluid are:
Heat Source
Heat sources are classified as:
