Around 3,000 ships have been fitted with WED and are generating huge savings as a direct benefit.
Wake Equalizing Duct (WED) is a system for improving ship propulsion and economic operation, developed by prof. Schneekluth in Cupertino with the research laboratory Duisburg.
SCHNEEKLUTH EQUALIZATION CHANNEL
FUEL SAVINGS UP TO 12%
*This means saving fuel or increasing speed
VIBRATION REDUCTION UP TO 50%
Significant reduction in material wear
Reduction of stress injuries
Protection of electronic equipment
More comfortable living and working conditions
Tremendous improvement in staff health
WED HAS THE SHORTEST PAYBACK TIME AND NO AFTER-COSTS!
The main advantage is energy saving, which is the result of various effects. These can be distinguished as follows:
– Improvement of propeller efficiency due to greater axial flow and more even distribution of speed over the surface of the disc. The first effect is more dominant. Measurements on a container ship model show that the angle of inclination of the inward flow in the plane behind the channel decreases from 20° to about 7° relative to the longitudinal axis of the ship. The asymmetrical arrangement of the half channels gives the water entering the propeller a direction of rotation opposite to the direction of rotation imparted by the propeller. Thus, the loss due to rotational energy when washing the propeller is smaller.
– Reduction of flow separation on the afterbody. This effect is the most widespread and is expressed in a decrease in the proportion of thrust reduction.
– Creating lift with a forward force component on the airfoil section in a similar way, but not as excessive as in the Kort channel.
– Steady flow reduces vibrations caused by the propeller. The refinement can be used for this purpose if initially poor flow conditions emerge, or it can be used to increase the diameter of the propeller because then smaller tip spacings become permissible, which in turn improves efficiency. This effect has not yet been tested.
– Reduction of propeller vibration due to reduced load on the propeller tip in the upper quadrants.
– Improved steering quality from a more balanced flow to the rudder. With vane rudders, longer upper sections become more efficient due to higher flow rates.
– Improved directional control due to the increased area of the rear side plane
– When the duct is retrofitted to an existing ship, there are no structural changes and no changes to the propeller design.
– It offers the possibility of installing devices to protect the propeller from ice.