Propulsion Improvements for Shallow Water Operation

[gf0012-aust]

Operating a vessel in shallow or unpredictable depths of water is a hazardous procedure. On one side safety requires erring on light loading, yet commercial considerations dictate having a fully laden vessel. As many of the navigable inland waterways of Europe are rivers, levels fluctuate with the seasons and affect loading levels of inland waterway barge traffic.

To improve propulsion efficiency under shallow water conditions, barges often use a tunnel duct to ensure the propeller receives sufficient water to provide propulsion however this brings a penalty in lost efficiency when operating in deeper water. In Holland alone, shallow water effects are estimated to have cost $39 million (Euro 28 million) over the last 20 years.


To improve propulsion efficiency under shallow water conditions, barges often use a tunnel duct to ensure the propeller receives sufficient water to provide propulsion however this brings a penalty in lost efficiency when operating in deeper water. In Holland alone, shallow water effects are estimated to have cost $39 million (Euro 28 million) over the last 20 years.

A specialist Dutch propulsion company, Van der Velden Marine Systems, has developed a shallow water propulsion system, together with the German research institute DST (Development Center for Ship Technology and Transport Systems). Called the Flex Tunnel, it is basically a retractable tunnel that allows free water flow to the propeller under normal conditions, yet be lowered in shallow waters to ensure adequate water is ducted over the propeller.

Vessels equipped with this system have smaller propellers and rudders reducing weight and draft, in addition, hull lines can be optimized giving increased loading capacity.

Usage statistics of full-load barge operation estimate that only 15 per cent of voyages are in shallow water therefore the Flex Tunnel offers substantial operational cost savings in lower fuel consumption and fuller loads.

Maritime Propulsion | Propulsion Improvements for Shallow Water Operation

another tech with impact on naval vessels and planning...

 

[kato]

another tech with impact on naval vessels and planning...

Only to a very limited extent in my opinion. The only thing where this may be really relevant in navy context is shore-to-shore logistics using small craft or barges in confined waters.
There are a handful countries for whom naval units capable of riverine and close-to-shore open-sea operations may be interesting. China and Brazil for example.

DST's industry research centers around improving efficiency for companies operating out of Duisburg harbour, in this case affecting primarily river-to-sea routes across the Channel to British ports. There aren't that many places in the world where river-to-sea, having to accomodate both open-sea and riverine shallow-water conditions, is as economically relevant as with the Rhine.

 

[gf0012-aust]

Only to a very limited extent in my opinion. The only thing where this may be really relevant in navy context is shore-to-shore logistics using small craft or barges in confined waters.
There are a handful countries for whom naval units capable of riverine and close-to-shore open-sea operations may be interesting. China and Brazil for example.

DST's industry research centers around improving efficiency for companies operating out of Duisburg harbour, in this case affecting primarily river-to-sea routes across the Channel to British ports. There aren't that many places in the world where river-to-sea, having to accomodate both open-sea and riverine shallow-water conditions, is as economically relevant as with the Rhine.

my main interest here is brownwater and ship to shore from dock ships