Stirling Machine Technology For Subsea Intervention Available to Purchase

Thermodynamically and mechanically ideal Stirling machines offer the greatest potential of any heat engine in terms of performance quality. This great potential has not been fully realised in practical designs but high performing Stifling machines have found a market in cryogenic and underwater power generation applications. In the latter case, over the last two decades, Stirling systems have been used, in a small 500 ton civilian manned research submarine and in medium-sized operational N~icken and Gotland class naval submarines of the Royal Swedish Navy, as auxiliary power units called Air Independent Propulsion systems (AIPs). Stirling systems have also been investigated for use as the main power units in smaller manned and unmanned autonomous underwater vehicles (AUVs) as well as diver propulsion devices/vehicles (DPD/Vs) and swimmer delivery vehicles (SDVs). In the post-Cold War environment the latter types of underwater vehicles are attracting increasing interest, particularly in the United States, as navies strive to develop the brown-water or littoral warfare capabilities necessary to prosecute operations in hostile coastal waters. Moreover, with offshore commercial oil and gas production moving into increasing deeper waters and other commercial and scientific ventures requiring AUVs of increasing endurance and under-ice capabilities there is a global interest in developing improved power systems for the new generation of underwater vehicles. The Stirling machine, with its proven record in the underwater environment, is an obvious candidate for such applications When their cycle of operations is reversed Stirling machines can be used not only to produce power but also to provide cooling, i.e. they can be refrigeration machines and excellent cryocoolers. Many of the emerging underwater technologies such as magnetohydrodynamics and superconducting machinery require cryogenic cooling facilities to operate effectively - as do many sensor systems and the Stirling cooling machines may have a role to play in such systems.