Prediction of fluctuations in propeller blade loads due to variation of wake velocity 

 over the propeller disc. 



Torque and thrust characteristics for fixed pitch and controllable pitch propellers 

 and interaction with hull under dynamic conditions. 



Factors influencing, and control of, wave induced transient vibration. 



Understanding of wave excited vibration. 



Vibration of surfaces moving through fluid (eg bottom panel of ship). 



Causes of cable vibration and its effect upon the drag characteristics of a towed 

 cable both plain and faired, including vortex shedding. 



Most of these suggestions emanate from non-university sources and, clearly, 

 propeller induced vibration and wave excited vibration are the favoured areas for 

 future work. From the data supplied it appears that only University College and 

 Newcastle have current work in the field of hydroelasticity, but the degree of detail 

 supplied does not enable much matching to be done with the proposed items. There 

 is probably very little overlap. However, there is some overlap and redundancy in the 

 proposed topics themselves and some could coalesce into single items. 



Field Reference 05 ' 



SHIP DESIGN - HULL LOADS AND SHIP MOTIONS 



Of interest to this section is the derivation of the forces acting on a ship's structure 

 in a seaway. These forces are a result of the passage of waves, the ship motions, and 

 the sloshing of liquid cargo, all of which create pressure forces and may cause impact 

 forces. An accurate definition of these forces is necessary before full advantage can 

 be taken of advances in stress analysis techniques. 



Work on ship motions is required to help define underkeel clearance in shallow 

 coastal waters; this is of particular concern to large tankers. The requirement is to 

 define the ship responses of pitch, heave and roll, and the sinkage effect caused by 

 the relative forward motion between the ship and the water. For all these, it will be 

 necessary to take account of the proximity of the sea bottom as it will influence the 

 hydrodynamic damping and added virtual mass associated with ship motions and 

 will also influence the sinkage effect caused by the restricted area of flow under the 

 keel. 



Recommended Topics 



General and local hydrodynamic loading on ships' structures owing to the effects 

 of wave action, ship motion and liquid cargo. 



The determination of added virtual mass and damping for ship shape forms for 

 three-dimensional flow in deep and shallow water. 



The determination of underkeel clearance for ships at various speeds in shallow 

 water with a seaway. 



The determination of propeller pressure forces and wake forces and moments. 



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