PD-31
The Japanese Marine Gas Turbine Project - SMGT
Takao SUGIMOTO*
Abstract
・Since 1997, five Japanese gas turbine makers have been developing a low-NOx, high-efficiency, next-generation, marine gas turbine (Super Marine Gas Turbine, or SMGT).
・The target goals for this 2,500kW class marine gas turbine include NOx emissions of less than 1 g/kWh, a thermal efficiency of 38-40%, and the ability to use fuel oil type A. The SMGT is being developed primarily as a main engine for coastal shipping vessels.
・The 6-year R&D plan calls for performance evaluation of a 2,500 kW class prototype gas turbine in the plan's final year. At present, research is underway on the following main components: the combustor, recuperator, compressors and turbines.
・To achieve the above goals, the following are being developed: a DLN combustor that can burn liquid fuel (fuel oil type A), a regenerative cycle using a plate-fin recuperator, a compound high-efficiency axial + radial compressor, and a high-efficiency cooled blades.
This paper outlines the current state of this research.
1. Introduction
In the face of growing environmental problems, land-based emission sources of atmospheric pollution have already been subject to stringent regulation. In 1997, the International Maritime Organization (IMO) adopted a new amendment to the MARPOL agreement regarding reduction of atmospheric pollution caused by shipping which has attracted worldwide attention. In Japan, survey data indicates that NOx emissions from ships within Japan's 200 nautical mile limit amounts to 37% of Japan's total NOx emissions. This has brought increasing attention to the amount of atmospheric pollution caused by shipping.
Gas turbines, due to their combustion process, produce significantly lower NOx emissions compared with diesel engines, and if gas turbines were widely used as ship engines it would result in a significant reduction of NOx emissions from ships.
In Japan there is an emergent recognition of the need for advancements in the maritime transport field. Coastal shipping in particular is in need of more modern ships - faster coastal vessels, improved shipboard environments and reduced on-board labor requirements. With its compact size, slight weight, low vibration levels, relatively quiet operation and ease of maintenance, the gas turbine has the potential to meet all these criteria.
However, due to high fuel consumption and other economic concerns, applications of gas turbines as marine engines have until now been limited.
The goal of this project is to overcome these concerns by developing a next-generation gas turbine with low NOx emissions and higher thermal efficiency, thus permitting a much wider application for its use as a marine engine.
In addition, because gas turbines require far less engine-room space than diesels, they permit increased freedom when designing ships and propulsion methods (including electric propulsion). More efficient hull designs could be used, which would further reduce the energy needed to propel them, creating the possibility for a comprehensive improvement in economy.
