Intercooled Gas Turbine Engine with a Bottoming Cycle

The Army's need for a compact, power dense gas turbine engine can be met by utilizing the heat rejected by the intercooler and exhaust of a intercooled engine. SatCon is in the process of building and testing a 500 HP, twin rotor, intercooled, turbo-alternator for the Chrysler Corporation. The power density of the engine, inclusive of the alternators, is better than 2.5 HP/lb electrical output. This turbo-alternator is an excellent platform for developing a bottoming cycle utilizing the heat rejection from the intercooler and the exhaust to enhance the power output and efficiency of the overall engine. Preliminary calculations show that the inclusion of a closed cycle (Rankine) steam turbine running off the intercooler and exhaust heat can almost double the engine power output. The closed cycle steam turbine clearly increases the complexity of the overall engine. The Phase I proposal is to design a closed cycle steam turbine engine as an "add on" to the existing 500 HP intercooled engine work and to study the trade-offs involved in increased power/efficiency and added complexity. A Phase II program will build a steam turbine engine and demonstrate and evaluate its performance as part of the existing 500 HP intercooled engine.