Gas turbine cycle is one of thermodynamic cycle processes. Rankine cycle uses steam as the working fluid. The Rankine cycle performance control is formed by the percentage of the existing highest and lowest cycle temperatures. The existing highest steam temperature in a Rankine cycle is about 1100 F (594 C), which usually is established mainly by material restrictions at the increased pressures of the cycles of steam. Just one indicates of advancing the performance control is to change the working fluid by using gas or air.
|Figure 1: Gas Turbine Cycle|
The gas turbine cycle process in the most basic form contains a turbine, combustor and also compressor as shown in Figure 1. Due to its simpleness, low budget fee and quick lead time period, gas turbine is now being applied by several utilities to increase capability in smaller batches. Utilization of the gas turbine cycle process in combination with Rankine cycle which uses steam can be an efficient indicates of recuperating several heat lost as soon as combustion gases are discharged to the environment at excessive temperatures.
In the basic gas turbine cycle process as demonstrated in Figure 1, air is pressurized then combined together with fuel and also burnt in the combustor. The gaseous combustion items which have high temperature get into turbine to generate work through expansion. A part of the work generated by turbine is utilized to generate the compressor and the rest is obtainable to generate power. The exhaust gases of turbine are subsequently vented to the environment. To assess the cycle, some simplifying suppositions are created.
First, however the process of combustion alters the working fluid arrangement, the fluid is addressed as a gas of individual arrangement all through, and it's deemed an suitable gas to get basic relationships among points in the process. Second, the process of combustion is assumed as a uncomplicated heat transfer process where the heat enter to the working fluid is established by the heating values of fuel. A outcome of this estimation is that the flow rate of mass as a result of the process stays consistent. The final estimation is to suppose that every of the functions which can be reversed internally.
When the expansion of turbine is finished with the exhaust gas at the similar pressure as the inlet air of compressor, the collaboration of operations could be considered as a cycle. The simple suppositions above provide the perfected gas turbine cycle known as air common Brayton cycle. Figure 2 below displays the cycle on P-v and Ts diagrams that allow identifying the condition parameters at the several cycle areas.
|Figure 2: Brayton Cycle|