Question

What effect has the Carnot efficiency had on the development of materials for gas turbines and aircraft engines

Answer 1

The maximum thermal efficiency any engine can reach is the Carnot efficiency. The energy efficiency of an internal combustion engine increases linearly with the combustion temperature (Carnot's cycle). To obtain maximum energy efficiency materials of turbines/engines must be suitable to work at high temperature conditions.The materials first developed for gas turbine engine applications had high temperature tensile strength as the prime requirement. This requirement quickly changed as operating temperatures rose(increasing carnot efficieny). Stress rupture life and then creep properties became important. This led to the development of the materials. In the subsequent years of development, low cycle fatigue (LCF) life became another important parameter for making turbines.