Integrated Ship Machinery Systems Revisited

Abstract

ABSTRACTIn the late 1980s, the world of U.S. Navy surface combatants is confronted with three new needs: to reduce ship signatures by factors of 10 to 1000; to provide ten‐gigawatt power pulses to new combat systems; and to reduce the high cost of hull, mechanical and electrical (HM&E) systems by taking advantage of newly‐available technology. These needs have caused an active response of the surface‐ship community to the many apparent benefits of integrated machinery systems.The acoustic signature problem accelerated interest in integrated machinery systems. A substantial reduction in noise at cruise speeds requires the elimination of propeller cavitation and requires reductions in machinery noise. The use of contrarotating tractor propellers driven by bicoupled epicyclic gears and an alternating‐current electric motor in a pod which faces directly into the flow stream is potentially capable of such performance; even better would be a contrarotating superconductive electric motor in the pod. No other concept seems even remotely competitive with these. The major reductions in installed power, fuel consumption, and reduced displacement reported in the April 1980 Naval Engineers Journal are retained. Large reductions in infrared signature and further reductions in fuel consumption are provided by intercooled recuperated gas turbines.An integrated electric propulsion system provides the opportunity to temporarily “borrow” power from the propulsion system and transform it into pulses for advanced combat systems. Not only the power of the turbines, but also the kinetic energy of the ship are available.