Figure 8 shows clearly that the propeller effect initially is amplified if the forward speed increases, until some critical value is exceeded. This value appears to depend on the ship-bank distance. The application point of the additional force due to propeller action appears to move forward with decreasing under keel clearance and increasing speed, and aft with decreasing bank clearance; this is illustrated in figure 9.
Fig.7. |
Ship model D, YB3> 0.78. Lateral force and yawing moment due to ship-bank interaction: effect of propeller action for several forward speeds and depth to draft ratios. |
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