Comparative Performance Study of Closed Cycle Gas Turbine Utilizing Cryogenic Cold
The re-evaporation of Liquefied Natural Gas (LNG) is capable of acting as a low temperature heat sink for power cycles, thereby enhancing the thermal efficiency of the cycle. Leaving aside the detail of the appropriate heat exchanger technology, the comparative performance of improved high and low temperature closed cycle gas turbines is investigated using non-dimensionalized performance analysis. It was shown that the effect of lowering the minimum cycle temperature on the efficiency is equivalent to raising the maximum cycle temperature by a multiple amount. The specific output, however, decreases to a fraction of that achieved by the cycle with the original minimum cycle temperature. Implications are drawn for the application of the closed cycle gas turbine utilizing cryogenic cold.