Fuel Consumption Calcs for ships

The engineering principle behind this ship fuel consumption and range calculation, which follows Australian Defence standards.

Core Principle: Ship Range Calculation Based on Fuel Consumption

The calculation determines how far a ship can travel based on:

1. Available Fuel - Starting with total fuel capacity and accounting for:

   • Tank fill percentage (not completely full for expansion)
   • Reserve requirements (safety margin)
   • Fuel for auxiliary vessels (ship's boats)

2. Power Requirements - The power needed changes based on:

   • Ship displacement (weight) - heavier ships need more power
   • Speed - power increases exponentially with speed
   • Wind resistance - headwinds require more power

3. Fuel Consumption Rate - Determined by:

   • Engine efficiency (kg of fuel per kW-hour)
   • Number of engines running
   • Electrical generation needs
   • Additional equipment

4. The Displacement-Power Relationship The formula Pb = A × displacement + B creates a linear relationship between ship weight and power needed. As fuel burns, the ship gets lighter, requiring less power.

5. Range Calculation The final range is calculated by determining how long the available fuel will last at the given consumption rate and speed.

Simple Analogy: It's like calculating how far your car can drive on a tank of gas, but accounting for the fact that the car gets lighter (and more efficient) as it burns fuel, plus considering headwinds and the need to keep some fuel in reserve for safety.