Posted on: January 26th, 2017 by admin

Exhaust Configurations for Generators

Generator exhaust can be one of the more troubling noises aboard your boat or yacht. Whether you have traveled to a quiet anchorage across the bay or halfway around the world, the thumping of diesel generator exhaust can ruin the peace and quiet you were searching for.

Soundown’s patented WaterDrop technology provides unmatched noise reduction for marine diesel generators in a number of configurations that can be customized to suit your vessel’s layout.

A key component of this technology is the separation of water and exhaust gas, which provides two advantages. The first is that the water is discharged below the hull to prevent the pulsing sound water makes otherwise as it exits the boat.  Without any water in the rest of the exhaust system, we can tune the reactive portion of the silencer more effectively, reducing the low frequency combustion tone of the engine.

All Soundown silencer and exhaust tubes are approved by Lloyd’s of London for use in vessels of appropriate size and service.

Soundown also provides equipment stack discharges for situations where additional measures are required to keep excess water and soot off  upper decks.

For vessels with extreme requirements for noise reduction Soundown offers 1/4 wave length resonators which virtually eliminate any noise from the exhaust.

The three standard configurations for Soundown’s WaterDrop silencers for generators are:

Each of these models has a number of inlet and outlet configurations that can be customized to the machinery arrangement. If you can provide us with drawings of your machinery space layout we can make the most effective recommendations for a system that will both fit your space and optimize noise reduction. Our systems include all the equipment needed to complete the installation, including fiberglass exhaust tube, spray rings or dry risers, marine exhaust hose and isolation mounts to support the installation.


This image shows a classic waterdrop with lift and sootsinker.generator-1-1 Vertical space is optimized in this configuration, which provides improved low-frequency performance. The optional sootsinker reduces the amount of soot that floats to the surface (and which can often result in complaints from marinas or other vessels).



This Axial Waterdrop uses the same technology as the Classic Waterdrop, with the chambers of the silencer arranged horizontally to fit in spaces where head room is limited. Axial Waterdrops are often placed on the hull side above other equipment or directly over the generator.



generator-3Combining the Waterlift and WaterDrop, this combi configuration is for areas with particularly limited space. The reduction in overall vibrational attenuation is less significant, but the system is easy to implement and makes very efficient use of space.


Stack Discharge
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This stack discharge configuration is used on larger vessels where the exhaust exits from the mast or upper deck. Any of the examples shown above can be designed for optional or full-time stack discharge with the addition of a mist collector and stack-tip heater. These components work to remove any condensate that otherwise forms in the vertical run and drips onto the upper deck. The mist eliminator strips any entrained water droplets, while the stack tip heater reducing the temperature disparity that causes condensation, preventing water droplets from forming at the end of the stack.


20-AM copySoundown’s tuned resonators are designed to trap the specific firing frequency of a diesel engine. They can be used as a secondary treatment for generators where the muffler is incorporated into the enclosure. And, for the lowest noise levels possible, they can serve as an after treatment to enhance Soundown Waterdrop systems.

See exhaust noise treatments for propulsion systems.