Supercharged Diesel engines are nowadays dominating naval propulsion. They have a thermal efficiency up to 50% and can swallow almost any liquid fuel. But there are two main drawbacks:
Nitrogen oxides emissions of Diesel engines are sometimes higher than desired.
Low speed vibrations can often be felt everywhere on the vessel. Some cruising ships therefore use gas turbines in spite of the lower thermal efficiency.
But instead of supercharging Diesel engines also gas turbines can be supercharged. In combination with recuperation they could achieve even a higher thermal efficiency than Diesel engines. Such a concept with the name “Semi-Closed Recuperated Cycle” (SCRC) has been proposed in [1] for replacing gas turbine combined cycles.
This paper shows new results of thermodynamic calculations of the SCRC with adiabatic or intercooled compressors. These calculations are optimized for naval applications with liquid fuels. The state of the SCRC technology is described with its expected operation, control concepts and limitations. Based on this investigation there is good evidence that supercharged Diesel technology for naval application could be seriously competed by the SCRC technology with respect to thermal efficiency, vibration (engine smoothness), emissions and specific mass (per kW power). It is the declared intention of the author to find companies who are interested in developing this technology.
