Ideal Brayton cycle efficiency for gas turbine with P V and T S diagram

The ideal cycle for gas turbine is Brayton or jule cycle. The Brayton cycle has two constant pressure and two isentropic processes. In this video, i have explained PV and TS diagram of Brayton cycle. This video will show you the Analysis of Brayton cycle, and at the end of the video, you will get the equation to find the thermal efficiency of a simple gas turbine power plant. The analysis of Brayton is carried out with the following assumptions: 1) Compression and expansion are isentropic. 2) Pressure losses in the system are neglected. 3) Heat losses in the system are neglected. 4) specific heat of working fluid is taken constant throughout the cycle. Considering the 1kg of working fluid.

Gas Turbine Engine Fuel

The gas turbine engine can be operated with gas, liquid and solid fuels. However, this statement is not true for all gas turbine engine. The selection of fuel for gas turbine is dependent on type of cycle, size and length of engine and application of gas turbine engine. The most important requirement of a gas turbine fuel are 
(1) composition should provide proper combustion and rapid burning,
(2) the product of combustion should contain a minimum of mater which might get deposited on the turbine blades or the heat exchanger,
(3) highest heating value per kg or m^3 volume specially for aircraft engine.


The modern gas turbine are normally operated on the following fuels:
a) Gaseous fuels: Natural gas, Blast furnace gas, Producer gas, Sewage gas, etc.…
b) Liquid fuels: Kerosene, Gasoline, Residual oils, etc.…
c) Solid Fuels: Coal


The solid fuel (Coal) is normally used in closed cycle gas turbine. The main problem with using solid fuel in the case of open cycle plans is of reducing the level of flyash in the gases leaving the combustion chamber so that the blades of the turbines are not eroded. For this, it is necessary to ensure proper cleaning of the combustion gases from fine ash and dust. Before the gas enters the turbine, it is purified with help of the various flyash collectors. The use of coal as a fuel of open cycle gas turbine is under the development. Coal is burnt in two methods. In the first method, the coal is completely or partially gasified and fuel gas produced is supplied to gas turbine combustor. In other method, pressurized bubbling or circulating fluidized bed, where fuel gas, after it is adequately filtered, expands in the gas turbine. Coal is usually considered as a gas turbine fuel in combined cycle power plant.

Liquid oil like kerosene, gasoline, etc. are easily used in a gas turbine combustor. Residual oils can be used as fuel in gas turbine. If the viscosity of the oil is high, some heating arrangement required.