Bulbous Bow — Volume & Area

Estimate bulb volume, projected frontal area & longitudinal position using empirical, ratio, or geometric modes.

Pick based on data you have.
For %LPP reporting.
Used for empirical & xb heuristic.

A) Empirical

Enter a positive number.
Enter a positive number.
0–1.
Used to report Vb/∇ ratio.
Uses a practical correlation for \(V_b/(LWL·B·T)\) vs \(C_B\). Projected area estimated from \(V_b^{2/3}\) scaling.
Result

Bulb Volume (Vb): — m³

Projected Area (Aproj): — m²

LCB of Bulb (xb fwd of FP): — m

Choose a method, enter inputs, and click Calculate.
Report: Bulbous Bow — Volume & Area
Method — —
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Method notes

Empirical: estimates \(V_b/(LWL·B·T)\) as a function of \(C_B\); projected area by \(V_b^{2/3}\) scaling; \(x_b \approx 0.05\,L_{WL}\) fwd of FP.

Manual Ratio: user supplies \(V_b/\nabla\), then \(V_b = (V_b/\nabla)\,\nabla\); projected area via \(V_b^{2/3}\) scaling; \(x_b \approx 0.05\,L_{WL}\).

Geometric Ellipsoid: \(V_b = \frac{\pi}{6}L_bB_bD_b\), \(A_{proj} = \frac{\pi}{4}B_bD_b\), \(x_b \approx 0.42\,L_b\) fwd of FP.

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