Theory 88/Energy Limits/Turbomachinery
Turbines Are Temperature Limited
The claim
Turbine efficiency is capped by the ratio of firing temperature to compressor discharge temperature, which materials and cooling set together.
01Mechanism
Thermal efficiency rises with the firing temperature, but the blade must survive it; cooling air costs efficiency, so the two trade.
02Prediction
Efficiency should track the ratio, with an optimum in cooling flow.
03Refutation
Efficiency tracking firing temperature alone would remove the cooling cost.