Early-Stage Analysis of Air Independent Propulsion Based on Fuel Cells for Small Submarines

This paper presents an analysis of the results of a hybrid air independent propulsion based on fuel cells for small submarines. The weight and volume of the investigated propulsion, and the major tactical and technical characteristics of the 540-tonne submarine equipped with this propulsion have been determined. Five onboard systems for the hydrogen storage or generation, and the oxygen storage are considered. Combining a micro-balloon hydrogen system with the cryogenic oxygen storage is the best solution for the propulsion. The submerged endurance and range improved 32.1-64.8 times, as compared to just battery. The indiscretion ratio equals zero at cruising speeds of less than 7.1 knots, while at higher speeds, this value has dramatically decreased, and submarine secrecy has increased significantly.