The Davis Sea Water Injection (SWI) plume cooling system is used to achieve a reduction in exhaust gas temperature for horizontal exhaust systems. The device can be specified to cool the gas to below 150 degrees C.

The SWI plume cooling system reduces plume temperature by injecting a fine water mist directly into the exhaust stream. The SWI system is located at the end of the exhaust duct and interfaces to the ship hull.

The SWI system relies on the evaporation of atomized water droplets in the exhaust to absorb thermal energy from the exhaust gas. The droplets are injected into the exhaust stream with a spray system which consists of an array of nozzles. These spray nozzles are supplied with sea water by either the fire fighting pumps or a separate pumping system.  The flow of the water is monitored and regulated by a control unit (the Onboard Signature Manager (OSM)) that interfaces to the ship integrated machinery control system (IMCS).

The SWI system is comprised of a water injection assembly followed by a length of duct over which the water droplets evaporate.

Davis has designed and supplied SWI systems for three different classes of ship.

Benefits of the SWI plume cooling system:

• Scalable to fit any size exhaust.

• Also acts as an IR signature suppression system for horizontal exhausts.

• Custom nozzle selection and placement ensures efficient use of sea water and uniform plume temperatures.