Other

USA As Represented by Secretary of the Navy

W Scott Finlayson

Marshall L Nuckols

Kenneth Price

Kirk Van Zandt

A catalytic heater supplies heated water that circulates to heat a diver's suit. An insulating housing closed at opposite ends by cap members defines a chamber containing a catalyst inside of a multi-tube heat exchanger. Fittings in the cap members pass water through the multi-tube heat exchanger to and from the suit, and a gas circuit flows mixed hydrogen and oxygen to the catalyst that reacts with the mixed hydrogen and oxygen to produce heat that heats the water in the multi-tube heat exchanger for the diving suit. Optionally, hydrogen may be mixed with oxygen from a breathing gas mixture so that after heating the water, the gases remaining may be breathed by the diver. The catalytic heater provides a safe, reliable source of warm water for active thermal protection of divers over a wide range of diving applications. The heater can be used in an open, closed or semi-closed configuration to support surface tethered diving applications or autonomous, self-contained missions with free-swimming divers or within wet or dry underwater vehicles. Water temperatures can be easily adjusted when using this heater by regulating the percentage of hydrogen injected into the bed of catalyst. The catalytic heater can be used either as the primary active heating source or as a backup heating system in the event failure occurs to the primary heat source.

Hot water heater for diver using hydrogen catalytic reactions

A semi-closed circuit rebreather system that adapts to a user's activity level is provided. A vacuum pressure develops in a chamber coupled to a mouthbit as a breathing gas is drawn by the user from the chamber. A positive pressure develops in the chamber as an exhalation gas is expelled by the user into the chamber. An open circuit is coupled to the chamber to supply an increasing mass of fresh make-up gas to the chamber as vacuum pressure in the chamber develops and increases. A closed circuit coupled to the chamber receives and processes the exhalation gas to produce a recycled gas suitable for breathing. No recycled gas is supplied to the chamber until a threshold vacuum pressure is reached therein. The threshold vacuum pressure is indicative of a higher level of respiratory minute volume (RMV). At that point, a volume of recycled gas is supplied to the chamber proportionally with respect to increases in the mass of fresh make-up gas as vacuum pressure increases beyond the threshold vacuum pressure. Thus, during higher levels of RMV, the recycled gas and fresh make-up gas mix in the chamber prior to inhalation therefrom.

Growing community of inventors

Annapolis, MD, United States of America

W Scott Finlayson