Aerothermal Design of a Multi-Stage Axial Flow Gas Turbine with Air Cooling

Abstract

The gas turbine engine is gaining acceptance throughout the world as a reliable, flexible and efficient base-load power generation plant. This is in addition to the fact that it has been the unrivalled working horse in aeroengines for decades. The more advanced the technology, the higher the turbine inlet temperature (TIT) is, which increases power, reduces weight and improves efficiency. This demands the use of advanced materials and cooling technology, and hence deeper understanding of aerothermal design becomes a premium. The study reported here shows how a simplified model for the flow in the annulus of the gas turbine can produce accurate results in relation to blade cooling. In this design, the axial, tangential and radial components of velocities are included, together with the compressibility effect and probability of introducing resonant forcing frequencies. This design exercise of finding the particulars of the geometry, gas angles, degree of reaction and cooling configuration represents the first step towards further analysis of heat transfer and overall performance. This could be carried out as a senior course project associated with a course on gas turbines and turbomachines.