Investigation of the Part-Load Performance of Two 1.12 MW Regenerative Marine Gas Turbines

Abstract

Regenerative and intercooled-regenerative shaft-power gas turbine engines of low pressure ratio have significant efficiency advantages over traditional aero-derivative engines of higher pressure ratios, and can compete with modern diesel engines for marine propulsion. The design-point performance is extremely sensitive to thermodynamic-cycle parameter choices. The type of components chosen affects power and efficiency significantly. The design-point and off-design-point performance of two 1.12 MW (1500 hp) regenerative gas turbines are predicted with computer simulations. One engine has single-shaft configuration, and the other has a gas-generator / power-turbine combination. The gas-generator / power-turbine engine arrangement is essential for wide off-design operating regime. The performance of each engine driving fixed-pitch and controllable-pitch propellers, or an AC electric bus (for electric-motor-driven propellers) is investigated. For commercial applications the controllable-pitch propeller may have efficiency advantages (depending on engine type and shaft arrangements). For military applications the electric drive provides better operational flexibility.