Aerodynamics of Compressors and Turbines (AE 651) Autumn Semester 2009 Instructor : Bhaskar Roy Professor, Aerospace Engineering Department I.I.T., Bombay e-mail : aeroyia@aero.iitb.ac.in 1
Axial Turbines Introduction Gas Turbine engine derives its name from the turbine, which is at the heart of the work producing mechanism of the engine. Principle A fluid with large kinetic energy content is allowed to hit a freely rotating set of blades, certain amount of energy can be extracted from the passing fluid as shaft power AE 651 - Prof Bhaskar Roy, IITB 2 Lect - 11
Axial Turbines Shaft energy from the turbine is used to run : i) The compressor, which raises the internal energy content of the fluid before it goes into the combustor, ii) A propeller to create the propulsive thrust AE 651 - Prof Bhaskar Roy, IITB 3 Lect - 11
Axial Turbines AE 651 - Prof Bhaskar Roy, IITB 4 Lect - 11
Axial Turbines (a) Multi-stage HP + LP turbine layout AE 651 - Prof Bhaskar Roy, IITB 5 Lect - 11
Axial Turbines (b) Elemental stage 6 6 AE 651 - Prof Bhaskar Roy, IITB Lect - 11
Axial Turbines Thermodynamic Properties in Turbine in a GTE Cycle 03 is the delivery from C.C. AE 651 - Prof Bhaskar Roy, IITB 7 Lect - 11
Axial Turbines Impulse turbines High energy flow is first accelerated and made to impinge on the rotor blade with high momentum and then made to take huge turn through the passage between the blades. Reaction turbines The flow is accelerated through the rotor blades by making an expanding (converging) curved nozzle passage, in addition to the large turning. Jet effect creates a reaction as per Newton’s 3 rd law of motion. AE 651 - Prof Bhaskar Roy, IITB 8 Lect - 11
Axial Turbines Axial flow turbine 2-D cascade velocity distribution AE 651 - Prof Bhaskar Roy, IITB 9 Lect - 11
Axial Turbines Axial flow turbine 2-D cascade velocity diagram Impulse turbines V 2 =V 3 reaction turbines V 3 >V 2 10 10 AE 651 - Prof Bhaskar Roy, IITB Lect - 11
Axial Turbines T-s of Axial Turbine Stage AE 651 - Prof Bhaskar Roy, IITB 11 Lect - 11
h-s Diagram of Axial Turbine Stage Axial Turbines 12 12 AE 651 - Prof Bhaskar Roy, IITB Lect - 11
Recommend
More recommend
