A new approach in combined cycles – low power unit for hybrid terrestrial propulsion. Performance assessment

摘要

The paper proposes a power generating solution for hybrid terrestrial propulsion, which consists in a Low Power Combined Cycle unit operating with natural gas (Compressed Natural Gas propulsion); the well-known benefits of the Combined Cycle power systems – high efficiency and low pollution – should thus become available in the terrestrial transport, a domain of great interest. The analyzed Combined Cycle system includes a gas turbine with heat exchanger and a steam turbine engine with two pressure levels. Performance indicators of this system – power output, efficiency, specific fuel consumption – are analyzed and optimized function of characteristic parameters of both gas and steam turbine engines. The study indicates higher performance of the proposed Combined Cycle unit compared to equivalent diesel engines (now available in much more environmentally friendly versions, operating with natural gas), which currently are the most efficient conventional power systems that operate with fossil fuel.