Design Considerations for Marine Gas Turbines

A gas-turbine engine employed as the main propulsion plant in a ship must satisfy design requirements which differ considerably from those for other turbine applications. The design objectives in a gas-turbine plant for application to naval vessels of medium displacement are discussed in this paper. Such vessels, notably escort types, have duty profile characteristics which demand relatively short periods of operation at maximum power, and long periods at small percentages of maximum power. Normal cruising power may be only 15 per cent of the maximum available but economy of operation must be assured at this condition. In this respect, such engines introduce problems which do not arise in commercial vessels or aircraft-machines, where most of the operating life is spent at high percentages of the maximum available power.