WASTE HEAT RECOVERY SYSTEM FOR A GAS TURBINE ENGINE AND CARBON DIOXIDE COMPRESSION SIMULATION

Abstract

The U.S. Department of Defense has implemented an initiative to become more energy efficient across all services. The Naval Postgraduate School supported development toward this goal by studying the possibility of energy generation using waste heat recovery within shipboard engine exhaust. This research included the development of a heat exchanger ultimately to use compressed CO2 as the working fluid to run a Brayton cycle. In support of this research, this thesis details the baselining and instrumentation of a Rolls Royce M250 helicopter engine in the Marine Propulsion test cell, which was used as the platform for this development. Additionally, a model of the heat exchanger design was fabricated and installed in the engine exhaust. The effects the installed heat exchanger has on engine performance was measured and analyzed. This thesis also examined the compressor to be used in the CO2 loop design. An ANSYS CFD model was developed and tested to create a compressor map of CO2 performance through a centrifugal compressor. The sheath and casing for the compressor were designed in SolidWorks and fabricated using a 3D printer. This thesis is critical in the continuing development of a shipboard waste heat recovery system.