1. What is a Prismatic Coefficient Calculator?

Definition: This calculator determines the prismatic coefficient (C_p) of a vessel based on displaced volume, diameter, and length.

Purpose: It helps naval architects and marine engineers evaluate the fullness of a ship's hull form.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( C_p \) — Prismatic coefficient (dimensionless)
• \( V \) — Displaced volume (m³)
• \( A_m \) — Midship section area (m², derived from diameter)
• \( L \) — Length (m)

Explanation: The displaced volume is divided by the product of midship area and length to determine hull fullness.

3. Importance of Prismatic Coefficient

Details: The prismatic coefficient affects resistance and powering characteristics, with values typically between 0.55-0.85 for most ships.

4. Using the Calculator

Tips: Enter the displaced volume in m³, diameter in meters (for circular cross-section), and length in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical prismatic coefficient range?
A: For displacement ships: 0.55-0.70, for high-speed vessels: 0.70-0.85.

Q2: How does prismatic coefficient affect performance?
A: Lower C_p generally means less resistance at low speeds, while higher C_p is better for high-speed vessels.

Q3: What if my cross-section isn't circular?
A: You would need to calculate the actual midship area rather than using the diameter.

Q4: Where do I find displaced volume?
A: From hydrostatic calculations, design drawings, or displacement measurements.

Q5: What's the relationship between C_p and block coefficient?
A: C_p = Block coefficient (C_b) / Midship section coefficient (C_m).